Can Diet Add Years To Your Life?

Which Foods Have The Biggest Effect On Longevity? 

Author: Dr. Stephen Chaney

Fountain Of YouthEveryone over 50 is searching for the elusive “Fountain Of Youth”.

  • We want to look younger.
  • We want to feel younger.
  • We want the energy we had in our 20s.
  • We want to be rid of the diseases of aging.

The list goes on!

But how do we do that? Pills and potions abound that claim to reverse the aging process. Most just reverse your wallet.

  • Should we train for marathons or bodybuilding contests?
  • Should we meditate or do yoga to relieve stress?
  • Should we get serious about losing weight?
  • Should we get more sleep?
  • Is there some miracle diet that can slow the aging process?

All the above probably slow the aging process, but the evidence is best for the effect of diet on aging. Several recent meta-analyses have looked at the effect of diet on the risk of premature deaths. In this issue of “Health Tips From the Professor” I review a study (LT Fadnes et al, PLoS Medicine, February 8, 2022) that combines the best of these meta-analyses into a single database and provides a provocative insight into the effect of diet on longevity.

How Was This Study Done?

Clinical StudyThis study combined data from recent meta-analyses looking at the impact of various food groups on the risk of premature deaths with the Global Burden of Disease Study which provides population-level estimates of life years lost due to dietary risk factors.

The authors then developed a new algorithm that allowed them to estimate how different diets affect sex- and age-specific life expectancy.

They divided the population into three different diet categories based on their intake of whole grains, vegetables, fruits, nuts, legumes, fish, eggs, dairy, refined grains, red meat, processed meat, white meat, sugar-sweetened beverages, and added plant oils. The diet categories were:

  • Typical Western Diet (TW). This diet was based on average consumption data from the United States and Europe. This was their baseline.
  • Optimal diet (OD). This diet is similar to a vegan or semi-vegetarian diet. However, it was not a purely vegan diet nor a purely semi-vegetarian diet. Instead, it represented the best diet people in this study were consuming.
  • Feasibility diet (FA). This diet recognizes that few people are willing to make the kind of changes required to attain an optimal diet. It is halfway between the Typical Western Diet and the Optimal Diet.

To help you understand these diets based on the foods the study participants were eating, here are the comparisons in terms of daily servings:

Food TW Diet FA Diet OD Diet
Whole grains 1.5 servings 4.3 servings 7 servings
Vegetables 3 servings 4 servings 5 servings
Fruits 2.5 servings 3.75 servings 5 servings
Nuts 0 serving* 0.5 serving* 1 serving*
Legumes 0 serving** 0.5 serving** 1 serving**
Fish 0.25 serving 0.5 serving 1 serving
Eggs 1 egg 0.75 egg 0.5 egg
Dairy 1.5 servings 1.25 servings 1 serving
Refined grains 3 servings 2 servings 1 serving
Red meat 1 serving 0.5 serving 0 serving
Processed meat 2 servings 1 serving 0 serving
White meat 0.75 serving 0.6 serving 0 serving
Sugar-sweetened beverages 17 oz 8.5 oz 0 oz
Added plant oils 2 tsp 2 tsp 2 tsp

*1 serving = 1 handful of nuts

**1 serving = 1 cup of beans, lentils, or peas

Using their algorithm, the authors asked what the effect on longevity would be if people changed from a typical western diet to one of the other diets at age 20, 60, or 80 and maintained the new diet for at least 10 years. The 10-year requirement is based on previous studies showing that it takes around 10 years for dietary changes to affect the major killer diseases like heart disease, cancer, or diabetes.

Finally, the authors improved the accuracy of their estimates of the effect of diet on longevity by taking into account the quality of each study included in their analysis. I will discuss the importance of this below.

Can Diet Add Years To Your Life?

The results were impressive.

The authors estimated that if people in the United States were to change from a typical western diet to an “optimal diet” and maintain it for at least 10 years,

…starting at age 20, men would live 13 years longer and women would live 10.7 years longer.

…starting at age 60, men would live 8.8 years longer and women would live 8 years longer.

…starting at age 80, both men and women would live 3.4 years longer.

But what if you weren’t a vegan purist? What if you only made half the changes you would need to make to optimize your diet? The news was still good.

The authors estimated that people in the United States were to change from a typical western diet to a “feasibility diet” and maintain it for at least 10 years,

…starting at age 20, men would live 7.3 years longer and women would live 6.2 years longer.

…starting at age 60, men would live 4.8 years longer and women would live 4.5 years longer.

…starting at age 80, both men and women would live ~2 years longer.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.”

Which Foods Have The Biggest Effect On Longevity?

The algorithm the authors developed also allowed them to look at which foods have the biggest effect on longevity. The authors estimated when changing from a typical western diet to an optimal diet, the greatest gains in longevity were made by eating:

  • More legumes, whole grains, and nuts, and…
  • Less red and processed meat.

The authors concluded, “An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains [in longevity].”

However, this conclusion needs to be interpreted with caution. We also need to recognize that an “optimal diet” was defined as the best diet people in this study were eating. In addition, the effect of different foods on longevity depends on:

  • The quality of the individual studies with that food, and…
  • The difference in consumption of that food in going from a western diet to an optimal diet.

For example:

  • Legumes, whole grains, nuts, red & processed meat made the list because the quality of data was high and the difference in consumption between the typical western diet and optimal diet was significant.
  • The quality of data for an effect of fruits and vegetables was also high. For example, one major study concluded that consuming 10 servings a day of fruits and vegetables a day reduces premature death by 31% compared to consumption of less than 1 serving a day. However, the difference in consumption of fruits and vegetables between the western and optimal diets in this study was small, so fruits and vegetables didn’t make the list.
  • Eggs and white meat didn’t make the list because the quality of data was low for those foods. Simply put,  that means that there was a large variation in effect of those foods on longevity between studies.
  • Other foods didn’t make the list because the quality of data was only moderate and/or the difference in intake was small.

So, the best way to interpret this these data is:

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve these benefits. In the words of the authors, “Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

What Does This Study Mean For You?

This study is the best of many studies showing the benefit of a more plant-based diet on health and longevity. It particularly encouraging because it shows:

  • You can achieve significant benefit by switching to a more plant-based diet late in life. You get the biggest “bang for your buck” if you switch at age 20. But even making the switch at age 60 or 80 was beneficial.
  • You don’t need to be a “vegan purist”. While the biggest benefits were seen for people who came close to achieving a vegan or semi-vegetarian diet, people who only made half those changes saw significant benefits.

As I said above, this is a very strong study. However, the underlying data come from association studies, which can have confounding variables that influence the results.holistic approach

For example, people who eat more plant-based diets tend to weigh less and exercise more. And both of those variables can influence longevity. Each study attempted to statistically correct for those variables, but they still might have a slight influence on the results.

However, I don’t see that as a problem because, in my view, a holistic approach is always best. As illustrated on the right, we should be seeking a lifestyle that includes a healthy diet, weight control, and exercise.

As for supplementation, both the vegan and semi-vegetarian diets tend to leave out whole food groups. Unless you are married to a dietitian, that means your diet is likely to be missing important nutrients.

The Bottom Line

A recent study asked whether changing from the typical western diet to a healthier, more plant-based diet could influence longevity. The results were very encouraging. The study showed that:

  • Changing to a healthier diet could add up to a decade to your lifespan.
  • The improvement in lifespan was greatest for those whose diets approached a vegan or semi-vegetarian diet, but a significant improvement in lifespan was seen for people who made only half those dietary improvements.
  • The improvement in lifespan was greatest for those who switched to a healthier diet in their 20’s, but significant improvements in lifespan were seen for people who didn’t change their diet until their 60’s or 80’s.

In terms of the foods that have the biggest effect on longevity.

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve those benefits.
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.

An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains. Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”

For more details about this study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Are We Killing Our Children With Kindness?

The Danger Of Ultraprocessed Foods 

Author: Dr. Stephen Chaney

fast foodIt breaks my heart when I see a mom and her children in the checkout line of a supermarket with a cart filled with sodas, sweets, and convenience foods and devoid of fresh fruits and vegetables – or when I see fast food restaurants packed with parents and their children.

I get it. Our kids love these foods. It seems like an act of kindness to give them the foods they crave. But are we killing our children with kindness?

Let me explain. The human brain is hardwired to crave sweets, salt, and fat. In prehistoric times each of these cravings had a survival benefit. For example:

  • Mother’s milk is naturally sweet. It only makes sense that babies should crave the nutrition source that is essential for their early growth and development.
  • Fruits provide a cornucopia of vitamins, minerals, and phytonutrients. But fruits were scarce and seasonal in prehistoric times. Their sweetness provided an incentive for early man to seek them out.
  • Some salt is essential for life. Yet in early history it was scare. It was worth its weight in gold.
  • In prehistoric times it was feast or famine. The human body has an unlimited capacity to store fat in times of plenty, and those fat stores carried early man through times of famine.

Today most Americans live in a time of food abundance. There are fast food restaurants on almost every street corner and in every shopping mall. We think of famine as the days we skipped lunch because we were busy.

Yet these cravings remain, and the food industry has weaponized them. They are churning out an endless supply highly processed foods and beverages. These foods are not being designed to improve their nutritional value. They are designed to satisfy our cravings and lure us and our children into consuming more of them every year.

Scientists have developed a classification system that assigns foods in the American diet to different groups based on the degree of processing of that food. As you might expect, the best classification is unprocessed foods. The worst classification is called “ultraprocessed foods”. [I will describe this classification system in more detail in the next section.]

It is time we asked how much ultraprocessed foods our children are eating and what it is doing to their health. That is the topic of the study (L Wang et al, JAMA, 326: 519-530, 2021) I will discuss today.

How Was This Study Done?

Clinical StudyThe data for this study were obtained from NHANES (National Health and Nutrition Examination Survey) dietary data collected from 33,795 American children (ages 2-19, average age = 10) between 1999 and 2018.

NHANES is a program conducted by the CDC to survey the health and nutritional status of adults and children in the United States. The survey has been conducted on a continuous, yearly basis since 1999.

The dietary data are collected via 24-hour dietary recalls conducted by trained interviewers, with a second recall administered over the phone 3-10 days later to improve the accuracy of the data.

  • Children aged 12-19 completed the dietary survey on their own.
  • For children aged 6-11, a parent or guardian assisted them in filling out the survey.
  • For children aged 2-5, a parent or guardian filled out the survey for them.

The foods and beverages consumed by the children were divided into 4 major groups based on the extent of processing using a well-established classification system called NOVA. The 4 groups are:

1) Unprocessed Or Minimally Processed Foods.

  • This includes whole foods and foods that are minimally processed without the addition of oils, fats, sugar, salt, or other ingredients to the food.
  • Examples of minimally processed foods include things like oatmeal, nut butters, dried fruit, frozen fruits or vegetables, and dried beans.

2) Processed Culinary Ingredients.

  • This includes recipes from restaurants or in-home cooking that add small amounts of oils, fats, sugar, salt, and seasonings to whole foods.

3) Processed Foods

  • This includes foods made in factories by the addition of salt, sugar, oil, or other substances added to whole or minimally processed foods.
  • Examples include tomato paste, canned fruits packed in sugar syrup, cheese, smoked or cured meat.

4) Ultraprocessed Foods

  • These are industrial formulations created in factories mostly or entirely from substances extracted from foods (oils, fats, sugar, starch, and proteins), derived from food constituents (hydrogenated fats and modified starch), or synthesized in laboratories (flavor enhancers, colors, and food additives).
  • Examples include sugar sweetened beverages; sweet or savory packaged snacks; chocolates and candies; burgers, hot dogs, and sausages; poultry and fish nuggets, pastries, cakes, and cake mixes.

Are We Killing Our Children With Kindness?

Obese ChildAs I said above, the important question is, “Are we killing our children with kindness when we give them the sugary drinks, sweets, convenience foods, and fast foods they crave?” After all, the foods we give them when they are young are the ones they are most likely to select when they get older.

Let’s start by looking at how pervasive these foods have become. That was the purpose of the study I am discussing today, and the results of this study are alarming. When they looked at the changes in food consumption by our children between 1999 and 2018:

  • The percentage of calories from ultraprocessed foods increased from 61.4% to 67%. That means:
    • Today, more than 2/3 of the calories our children consume daily come from ultraprocessed foods!
  • The percentage of calories from unprocessed and minimally processed foods decreased from 28.8% to 23.5%. That means:
    • In the span of just 19 years the diets of our children have gone from bad to worse!
  • Ultraprocessed foods were more likely to be consumed away from home and at fast food restaurants.

When the investigators looked at individual categories of ultraprocessed foods:

  • The percentage of calories coming from ready to heat and eat dishes like frozen pizzas and other frozen meals or snacks increased from 2.2% to 11.2%.
  • The percentage of calories coming from sweet snacks and desserts increased from 10.7% to 12.9%.
  • The percentage of calories coming from sugar sweetened beverages decreased from 10.8% to 5.3%.
    • This is potentially the only good news from this study.

The authors concluded. “Based on NHANES data from 1999 to 2018, the estimated energy intake from consumption of ultraprocessed foods has increased among youths in the US and has consistently comprised the majority of their total energy intake.”

“These results suggest that food processing may need to be considered as a food dimension in addition to nutrients and food groups in future dietary recommendations and food policies.”

The Danger Of Ultraprocessed Foods

Fast Food DangersThis study clearly shows that ultraprocessed foods have become the mainstay of our children’s diets. Forget a balanced diet! Forget “Eat your fruits and vegetables”! Our children’s diets have been fundamentally transformed by “Big Food, Inc”.

You might be saying to yourself, “So, they are eating their favorite processed foods. What’s the big deal? How bad can it be?” My answer is, “Pretty Bad”. I chose the title, “Are we killing our children with kindness”, for a reason.

When you look at what happens to children who eat a diet that is mostly ultraprocessed foods:

#1: Their nutrition suffers. When the investigators divided the children into 5 groups based on the percentage of calories coming from ultraprocessed foods, the children consuming the most ultraprocessed food had:

  • Significantly higher intakes of carbohydrates (mostly refined carbohydrates); total fats; polyunsaturated fats (mostly highly processed omega-6-rich vegetable oils); and added sugars.
  • Significantly lower intakes of fiber; protein; omega-3 polyunsaturated fatty acids; calcium; magnesium; potassium; zinc; vitamins A, C, D, and folate.
    • The low intake of fiber means our children will be less likely to have health-promoting friendly bacteria and more likely to have disease-promoting bad bacteria in their guts.
    • The low intake of calcium, magnesium, and vitamin D means they will be less likely to achieve maximum bone density as young adults and will be more likely to suffer from osteoporosis as they age.

#2: They are more likely to become obese. Remember, these are foods that are made in a factory, not grown on a farm.

  • They are high in fat, sugar, and refined carbohydrates. That means they have a high caloric density. Each bite has 2-3 times the calories found in a bite of fresh fruits and vegetables.
  • As I said earlier, the food industry has weaponized our natural cravings for sweet, salty, and fatty foods. They feed their prototypes to a series of consumer tasting panels until they find the perfect blend of sugar, salt, and fat to create maximum craving.
  • And if that weren’t enough, they add additives to create the perfect flavor and “mouth appeal”.
    • It is no wonder that clinical studies have found a strong correlation between high intake of ultraprocessed food and obesity in both children and adults.
    • It is also no wonder that the rate of childhood obesity has almost quadrupled (5% to 18.5%) in the last 40 years.

#3: They are more likely to become sick as adults and die prematurely.

  • Obesity; high intake of fat, sugar, and refined carbohydrates; and low intake of fiber, omega-3s, and essential nutrients all contribute to an increased risk of diabetes, heart disease, and some cancers.
    • It is no wonder that clinical studies have found a strong correlation between high intake of ultraprocessed food and increased risk of diabetes, heart disease, some cancers, and premature death in adults.
    • It is also no wonder a recent study found that type 2 diabetes in children has almost doubled between 2001 and 2017.

The data are clear. When we allow our children to subsist on a diet mostly made up of the ultraprocessed foods they crave, we may be giving them, not love, but a lifetime of obesity and declining health instead. And yes, we may be killing them with kindness.

Instead, my recommendations are:

  • expose your children to a variety of fresh fruits, vegetables, and minimally processed foods at an early age.
  • They will reject some of them, and that’s OK. Introduce others until you find whole, minimally processed foods they like. Reintroduce them to some of the foods they initially rejected as they get older.
  • Don’t keep tempting ultraprocessed foods in your house.
  • You may just succeed in putting your children on the path to a healthier diet and a healthier, longer life.

The Bottom Line

It breaks my heart when I see a mom and her children in the checkout line of a supermarket with a cart filled with sodas, sweets, and convenience foods and devoid of fresh fruits and vegetables – or when I see fast food restaurants packed with parents and their children.

I get it. Our kids love these foods. It seems like an act of kindness to give them the foods they crave. But are we killing our children with kindness?

It is time we asked how much ultraprocessed foods our children are eating and what it is doing to their health. A recent study did just that. When they looked at the changes in food consumption by our children between 1999 and 2018:

  • The percentage of calories from ultraprocessed foods increased from 61.4% to 67%. That means:
    • Today, more than 2/3 of the calories our children consume daily come from ultraprocessed foods!
  • The percentage of calories from unprocessed and minimally processed foods decreased from 28.8% to 23.5%. That means:
    • In the span of just 19 years the diets of our children have gone from bad to worse!

This study clearly shows that ultraprocessed foods have become the mainstay of our children’s diets. Forget a balanced diet! Forget “Eat your fruits and vegetables”! Our children’s diets have been fundamentally transformed by “Big Food, Inc”.

You might be saying to yourself, “So, they are eating their favorite processed foods. What’s the big deal? How bad can it be?” My answer is, “Pretty Bad”. I chose the title, “Are we killing our children with kindness”, for a reason.

When you look at what happens to children who eat a diet that is mostly ultraprocessed foods:

  • Their nutrition suffers.
  • They are more likely to become obese.
  • They are more likely to become sick as adults and die prematurely.

For more details about this study, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

How Does Red Meat Cause Colon Cancer?

How Can You Decrease Your Risk Of Colon Cancer? 

Author: Dr. Stephen Chaney

Grilled HamburgersBoth red meat and processed meat consumption are associated with increased risk of colon cancer. But the strength of that association differs between the two.

Processed meat has been classified as a carcinogen by the IARC*, indicating the evidence that processed meat causes colon cancer is definitive. Red meat, on the other hand, has been classified as a probable carcinogen by the IARC*. That means the evidence that red meat causes colon cancer is strong, but not definitive.

*[In case you were wondering, the IARC (International Agency for Research on Cancer) is an international agency charged by the WHO to, among other things, determine the risk of cancer from various foods, industrial chemicals, and environmental pollutants.]

As I said above, red meat consumption is associated with increased risk of colon cancer. But…

  • Not all studies agree (more about that later), and…
  • Association doesn’t prove cause and effect. It could be some other characteristic of red meat eaters that increases their risk of colon cancer.
  • Until recently we had no clear idea of how red meat might cause colon cancer.

Several mechanisms have been proposed. I will discuss each mechanism and ways to reduce the risk of colon cancer by that mechanism:

#1: When fat and juices from the meat drip onto an open flame, carcinogenic polyaromatic hydrocarbons (PAHs) Barbecue Gatheringare formed that stick to the surface of the meat. PAHs can be metabolized to cancer causing chemicals in our body.

  • PAH formation can be reduced by marinating the meat prior to cooking or by using cooking techniques that don’t involve an open flame.
  • PAH formation can be reduced, but not eliminated, by lower fat meat choices, such as grass-fed beef.
  • High fiber diets reduce exposure to PAHs by binding to them and flushing them through the intestine.
  • Cruciferous vegetables block the conversion of PAHs to cancer causing chemicals in our body.

#2: When red meats are cooked at high temperatures, amino acids in the meat combine with creatine, which is found in all red meats, to form heterocyclic amines (HCAs). HCAs can also be metabolized to cancer causing chemicals in our body.

  • HCA formation can be reduced by cooking the meat at lower temperatures.
  • Grass-fed beef does not reduce HCA formation because this mechanism is not dependent on the fat content of the meat.
  • High fiber diets and cruciferous vegetables reduce the danger of HCAs by the same mechanisms as for PAHs.

#3: The nitrates and nitrites used as preservatives in many processed meats react with amino acids from the meat to form carcinogenic N-nitrosamines in our intestines.

  • Antioxidant-rich fruits and vegetables can divert nitrates and nitrites into an alternative pathway that coverts them into nitric oxide, which is beneficial to our bodies. I have discussed this in a previous issue of “Health Tips From the Professor”.

#4: Heme, which is found in all red meats, combines with amino acids in the meat to form carcinogenic N-nitrosamines and similar N-nitroso compounds in our intestines.

  • This mechanism is inherent in all red meats and cannot be eliminated by choosing grass-fed beef or cooking at lower temperatures.
  • The formation of N-nitroso compounds from red meat appears to be carried out by gut bacteria. We know that meat eaters and vegetarians have very different populations of gut bacteria, but we don’t know whether this influences N-nitroso formation.

Mechanism #4 (formation of N-nitroso compounds from heme-containing red meat in our intestines) is the one I will be discussing in this article. But first, it’s time for Metabolism 101.

Metabolism 101: Why Should We Fear N-Nitroso Compounds?

ProfessorSimply put, N-nitroso compounds react with our DNA. They transfer methyl and ethyl groups to the nucleotides that make up our DNA sequence. The general term for these reactions is alkylation of the DNA.

  • In some cases, this causes the alkylated nucleotides to miscode during DNA replication. This can lead to cancer causing mutations.
  • In other cases, this causes genes to be permanently turned on or off.

To understand why this is a problem, you need to know a bit about cancer cell biology.

  • We have certain genes called “oncogenes”. These are genes that turn on processes like cell division. Normally these genes are tightly regulated so that cell division only occurs when it is needed. When these genes are permanently turned on, unregulated, continuous cell division occurs. In short, the cell becomes a cancer cell.
  • We have other genes called “tumor suppressor genes”. These are genes that do things like shutting down cell division when it is not needed. When these genes are permanently turned off, unregulated cell division can occur.

With this in mind, let us review what we know about red meat and colon cancer:

  • Red meat consumption is associated with increased risk of colon cancer.
  • Red meat consumption is also associated with increased concentrations of N-nitroso compounds in the colon. Studies also show:
  • The formation of N-nitroso compounds correlates with the heme content of the meat.
  • The formation of N-nitroso compounds in the colon is dependent on certain strains of gut bacteria.
  • The formation of N-nitroso compounds is reduced by diets high in fiber. It is likely this is because high fiber diets influence the types of bacteria in the colon, but that has not been proven yet.

What is missing is evidence that colon cancer cells contain the kind of DNA modifications (DNA alkylation) caused by N-nitroso compounds. That is what the current study (C Gurjao et al, Cancer Discovery, published online June 17, 2021) was designed to test.

How Was This Study Done?

Clinical StudyOne reason previous studies had not been able to demonstrate a clear correlation between red meat consumption and DNA modifications was that the studies were too small to obtain statistically significant results.

So, the authors of this study combined data from women in the Nurses’ Health Study, the Nurses’ Health Study II, and men in the Health Professionals Follow-Up Study. There were over 238,130 women and 51,529 men in these three studies.

None of the participants had cancer at the time they entered the studies. The participants were followed for at least 27 years. During that time 4855 participants developed colon cancer.

At the beginning of each study and every 4 years later the participants were asked to fill out a food frequency questionnaire to collect information about their usual diet over the past year. Validation studies showed that the diets of the participants changed little over the interval of the studies.

The participants in these studies were sent follow-up questionnaires every two years to collect information on lifestyle and newly diagnosed diseases like colon cancer.

For those who developed colon cancer, their medical records were reviewed to collect data on tumor size, tumor location, and disease stage.

The diagnoses of colon cancer often involves removing tissue from the cancer and from surrounding normal tissue and putting it in formalin-fixed paraffin-embedded tissue blocks. These were collected, and the DNA was extracted and sequenced to determine the extent and genetic location of alkylated DNA sequences.

How Does Red Meat Cause Colon Cancer?

colon cancerThis study measured the effect of red meat consumption on the extent and location of what the authors called “alkylation signatures”, which refers to the kinds of DNA modifications caused by N-nitroso compounds. Here is what they found:

  • Red meat consumption was positively associated with an increase in alkylation signatures caused by N-nitroso compounds in tumor tissue from patients with colon cancer.
    • This was true for both processed and unprocessed red meat.
    • There was no difference between men and women after adjusting for differences in red meat intake.
    • White meat (chicken and fish) did not cause an increase in alkylation damage in colon cells.
  • More importantly, there was an inverse association between alkylation damage in the tumor tissue and patient survival. Simply put, high levels of alkylation damage were associated with short survival times.

Previous studies have shown that processed red meat consumption was associated with increased levels of N-nitroso compounds and an increased risk of colon cancer in the distal colon.

  • This study showed colon cancer patients who had been consuming processed red meats had higher alkylation damage in tumors in the distal colon.

Previous studies have shown that certain oncogenes (genes that drive the conversion of normal cells to cancer cells) are activated in colon cancer cells and this activation is associated with alkylation damage to their DNA.

  • This study showed that tumors with activated oncogenes were enriched with the alkylation signature characteristic of N-nitroso compounds.

I realize this study is highly technical. It is not easy to understand, so let me simplify it.

  • Previous studies have shown that red meat consumption is associated with an increased risk of colon cancer.
  • Previous studies have also shown that red meat consumption is associated with an increased concentration of carcinogenic N-nitroso compounds in the colon.
  • This study shows that red meat consumption is associated with the kind of DNA damage caused by N-nitroso compounds in colon tumor cells. More importantly, this is the kind of damage that can lead to cancer-causing mutations. In addition:
    • The DNA damage occurs in the exact location of the colon predicted from earlier studies.
    • The DNA damage occurs in genes known to drive the conversion of normal colon cells to cancer cells.

In short, this study provides a plausible mechanism for the effect of red meat consumption on increased risk of colon cancer. It shows how red meat can cause colon cancer.

“In the words of the authors, “Our study has leveraged a comprehensive dataset with repeated dietary measures over years…and [DNA sequencing] on a large collection of colorectal tumors. It provides unique evidence supporting the direct impact of dietary behaviors on colorectal carcinogenesis…”

How Can You Decrease Your Risk Of Colon Cancer?

Steak SaladWhen this study is combined with previous studies, it provides a clear explanation of how red and processed meats can cause colon cancer. And, unfortunately, grass-fed beef is not a “Get Out Of Jail Free” card. This mechanism is equally applicable to grass-fed beef and conventionally raised beef.

Does this mean you need to become a vegan? While I have nothing against veganism, the answer appears to be no. As I discussed above whole, unprocessed plant foods are the antidote to the carcinogenic compounds formed from red meat. This is due to:

  • Their fiber, which sweeps some carcinogens out of the intestine before they can be absorbed.
  • Their antioxidants, which prevent some carcinogens from being formed.
  • Their phytonutrients, which block the activation of some carcinogens.
  • The friendly gut bacteria they support, which displace the bad bacteria that form some carcinogen precursors in the intestine.

The good news is that some red meat may be OK in the context of a primarily plant-based diet. For example, 3 ounces of red meat in a green salad or stir fry is less likely to increase your risk of colon cancer than an 8-ounce steak and fries.

The bad news is this is why not all studies have shown an association of red meat consumption and increased risk of colon cancer. Unfortunately, far too many of these studies have ignored other components of the diet.

The Bottom Line

A recent study looked at the effect of red meat consumption on DNA modifications in colon cells that are associated with the conversion of normal cells to cancer cells. It is a highly technical study, but the simplified version is:

  • Previous studies have shown that red meat consumption is associated with an increased risk of colon cancer.
  • Studies have also shown that red meat consumption is associated with an increased concentration of carcinogenic N-nitroso compounds in the colon.
  • This study shows that red meat consumption is associated with the kind of DNA damage caused by N-nitroso compounds in colon tumor cells – the kind of damage that can lead to cancer-causing mutations. In addition:
    • The DNA damage occurs in the exact location of the colon predicted from earlier studies.
    • The DNA damage occurs in genes known to drive the conversion of normal colon cells to cancer cells.

In short, this study provides a plausible mechanism for the effect of red meat consumption on increased risk of colon cancer. It shows how red meat can cause colon cancer.

“In the words of the authors, “Our study has leveraged a comprehensive dataset with repeated dietary measures over years…and [DNA sequencing] on a large collection of colorectal tumors. It provides unique evidence supporting the direct impact of dietary behaviors on colorectal carcinogenesis…”

For more details about this study and how you can eat red meat and still reduce your risk of colon cancer, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Best Way To Reduce Risk Of Breast Cancer

What Does The American Cancer Society Say About Reducing Breast Cancer Risk? 

Author: Dr. Stephen Chaney

breast cancerBreast cancer is a scary disease. The American Cancer Society tells us:

  • 281,000 women will be diagnosed with invasive breast cancer in 2021.
  • 43,000 women will die from breast cancer in 2021.
  • The good news is that both prevention and treatment of breast cancer have gotten much better:
    • The 5-year survival rate is 90%.
    • The 10-year survival rate is 84%.
    • For women over 50 the death rate has decreased by 1%/year between 2013 and 2018 (mainly due to recognition that hormone replacement therapy is a risk factor for breast cancer).
  • The bad news is:
    • The cost of breast cancer treatment can range from $50,000 to over $180,000.
    • The side effects of breast cancer treatment can be brutal.
      • For example, there is an effective treatment to prevent breast cancer recurrence for some forms of breast cancer, but many women discontinue the treatment after a few years because of the side effects.

So, wouldn’t it be wonderful if there were some simple changes you could make that would dramatically reduce your risk of developing breast cancer in the first place? There are lots of options for reducing your risk of developing breast cancer, but which one(s) should you choose?

  • Dr. Strangelove and his friends are only too happy to recommend their favorite potion, food, or diet.
  • There are long lists of foods you should avoid if you want to reduce your risk of breast cancer.
  • There are also lists of harmful chemicals in cleaners and other household products that you should avoid.

It can become confusing. It can become overwhelming. It would be easy to just throw up your hands and say, “I give up. I don’t know what to do.”

You may be thinking, “Why doesn’t someone simplify things by identifying the top few lifestyle changes that are most effective for reducing my risk of developing breast cancer?”

It turns out someone has. Today I will share two recent studies that have identified the top 6 strategies for reducing your risk of breast cancer, and I have ranked them from 1 to 6 in order of effectiveness.

What Is The Best Way To Reduce Risk Of Breast Cancer?

AwardThe first study (RM Tamimi et al, American Journal of Epidemiology, 184: 884-893, 2016 was designed to identify the major modifiable risk factors for invasive, postmenopausal breast cancer (The term “modifiable risk factors” refers to those risk factors that are under your control.

The study utilized data collected from the Nurses’ Health Study between 1980 and 2010. During that time 8,421 cases of invasive breast cancer were diagnosed in 121,700 postmenopausal women in the study. The study looked at the effect of nonmodifiable and modifiable risk factors on the development of invasive breast cancer in these women.

  • Nonmodifiable risk factors included current age, age at which menstruation began, height, age of first birth, number of births, weight at age 18, family history of breast cancer, and prior benign breast disease.
  • Modifiable risk factors included weight change since age 18, alcohol consumption, physical activity level, breastfeeding, and postmenopausal hormone therapy use.

Here were the results from the study:

  • All the risk factors included in this study accounted for 70% of the risk of developing invasive breast cancer in postmenopausal women.
  • Modifiable risk factors accounted for 34.6% of the risk of developing invasive breast cancer in postmenopausal women.

When they analyzed the effect of modifiable risk factors on the risk of developing invasive breast cancer separately:

  • 44 pounds of weight gain since age 18 increased the risk by 50%.
  • Postmenopausal hormone replacement use increased the risk by 35%.
  • More than one alcoholic beverage/day increased the risk by 32%.
  • Low physical activity increased the risk by 7%.
  • Lack of breastfeeding increased the risk by 5%.

What About The Effect Of Diet On Breast Cancer Risk?

You may be wondering, “What about the effect of a healthy diet on my risk developing invasive breast cancer?” Unfortunately, the study I described above completely disregarded the effect of diet on breast cancer risk.

However, the second study (MS Farvid et al, International Journal of Cancer, 144: 1496-1510, 2019) I will discuss today partially addresses this issue. It uses the same database as the first study and looks at the effect of fruit and vegetable consumption on the risk of developing invasive breast cancer.

When this study compared high versus low intake of fresh fruits and vegetable on the risk of developing invasive breast cancer:

  • Women eating >5.5 servings/day of fruits and vegetables had a 11% lower risk than women consuming ≤2.5 servings/day.
  • Women consuming >2.5 servings/day of fruit had a 9% lower risk than women consuming ≤0.5 servings/day.
  • Women consuming >4.5 servings/day of vegetables had a 9% lower risk than women consuming ≤0.5 servings/day.

While all fresh fruits and vegetables contributed to this effect:

  • The most protective fruits were berries and cantaloupe & melons.
  • The most protective vegetables were yams & sweet potatoes, green leafy vegetables (such as kale, mustard greens, and chard), and cruciferous vegetables (such as Brussels sprouts).

The authors concluded, “Our findings support that higher intake of fruits and vegetables, and specifically cruciferous and yellow/orange vegetables, may reduce the risk of breast cancer, especially those that are more likely to be aggressive tumors.”

Now we are ready to answer your question, “Which lifestyle changes are most effective for reducing your risk of developing breast cancer?” If we combine the two studies and rank order the modifiable risk factors, it would look like this.

#1: Minimize weight gain during your adult years.

#2: Don’t use postmenopausal hormone replacement therapy unless absolutely necessary.

#3: Drink little or no alcohol.

#4: Eat a healthy diet with lots of fresh fruits and vegetables.

#5: Be physically active.

#6: Breastfeed when possible.

What Does The American Cancer Society Say About Reducing The Risk Of Breast Cancer?

American Cancer SocietyThe advice of the American Cancer Society is remarkably similar. Here are their recommendations:

  1. Get to and stay at a healthy weight.

After menopause, most of your estrogen comes from fat tissue. Having more fat tissue increases the amount of estrogen your body makes, raising your risk of breast cancer. Also, women who are overweight tend to have higher levels of insulin. Higher insulin levels have also been linked to breast cancer.

If you are already at a healthy weight, stay there. If you are carrying extra pounds, try to lose some. Losing even a small amount of weight can also have other health benefits and is a good place to start.

3) Be physically active and avoid time spent sitting.

Current recommendations are to get at least 150-300 minutes of moderate intensity or 75-150 minutes of vigorous intensity activity each week. Getting to or exceeding 300 minutes is ideal.

In addition, you should limit sedentary behavior such as sitting, lying down, watching TV, and other forms of screen-based entertainment. This is especially important if you spend most of your working day sitting.

3) Follow a healthy eating plan.

A healthy eating pattern includes a variety of vegetables, fiber-rich legumes (beans and peas), fruits in a variety of colors, and whole grains. It is best to avoid or limit red and processed meats, sugar-sweetened beverages, highly processed foods, and refined grain products. This will provide you with key nutrients in amounts that help you get to and stay at a healthy weight.

4) It is best not to drink alcohol.

Research has shown that drinking any alcohol increases the risk of breast cancer. If you choose to drink alcohol, the American Cancer Society recommends that women have no more than 1 alcoholic drink on any given day. A drink is 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of hard liquor.

5) Think carefully about using hormone replacement therapy.

Studies show that HRT using a combination of estrogen and progestin increases the risk of breast cancer. This combination can also lead to increased breast density making it harder to find breast cancer on mammogram.

Talk with your doctor about all the options to control your menopause symptoms, including the risks and benefits of each. If you decide to try HRT, it is best to use it at the lowest dose that works for you and for as short a time as possible.

The Bottom Line

Breast cancer is a scary disease. The good news is that detection and treatment of breast cancer has improved over the past decade. The bad news is that treatment is expensive, and the side effects can be brutal.

There are lots of options for reducing your risk of developing breast cancer, but which one(s) should you choose?

  • Strangelove and his friends are only too happy to recommend their favorite potion, food, or diet.
  • There are long lists of foods you should avoid if you want to reduce your risk of breast cancer.
  • There are also lists of harmful chemicals in cleaners and other household products that you should avoid.

It can become confusing. It can become overwhelming. It would be easy to just throw up your hands and say, “I give up. I don’t know what to do.”

You may be thinking, “Why doesn’t someone simplify things by identifying the top few lifestyle changes that are most effective for reducing my risk of developing breast cancer?”

It turns out someone has. Today I will share two recent studies that have identified the top 6 strategies for reducing your risk of breast cancer, and I have ranked them from 1 to 6 in order of effectiveness in the article above.

For more details about these studies, my ranking of the top 6 strategies for reducing your risk of breast cancer, and the American Cancer Society recommendations, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

What Is An Anti-Inflammatory Diet?

Can Diet Douse The Flames?

Author: Dr. Stephen Chaney

InflammationIf you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It is something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. How good is the evidence that certain foods influence inflammation, and what does an anti-inflammatory diet look like?

The Science Behind Anti-Inflammatory Diets

ScientistLet me start by saying that the science behind anti-inflammatory diets is nowhere near as strong as it is for the effect of primarily plant-based diets on heart disease and diabetes. The studies on anti-inflammatory diets are mostly small, short duration studies. However, the biggest problem is that there is no standard way of measuring inflammation.

There are multiple markers of inflammation, and they do not change together. That means that in every study some markers of inflammation are altered, while others are not. There is no consistent pattern from one study to another.

In spite of these methodological difficulties, the studies generally point in the same direction. Let’s start with the strongest evidence and work our way down to the weakest evidence. 

Omega-3 fats are anti-inflammatory (I. Reinders et al, European Journal of Clinical Nutrition, 66: 736-741, 2011). The evidence is strongest for the long chain omega-3s found in fish and fish oil, but the shorter chain omega-3s found in foods like walnuts, flaxseeds, chia seeds and flaxseed oil, soybean oil, and canola oil also appear to be anti-inflammatory. 

Inflammation is directly correlated with glycemic index (L. Qi and F.B. Lu, Current Opinion in Lipidology, 18: 3-8, 2007). This has a couple of important implications.

The most straightforward is that refined carbohydrates and sugars (sodas, pastries, and desserts), which have a high glycemic index, increase inflammation. In contrast, complex carbohydrates (whole grains, most fruits and vegetables) decrease inflammation. No surprise there. The second implication is that it is the glycemic index, not the sugar, that is driving the inflammatory response.

That means we need to look more closely at foods than at sugars. Sodas, pastries and desserts are likely to cause inflammation, but sugar-containing foods with a low glycemic index are unlikely to be inflammatory. 

Fruits and vegetables are anti-inflammatory. This has been shown in multiple studies. At this point most of the research is centered on identifying the nutrients and phytonutrients from fruits and vegetables that are responsible for the reduction in inflammation. I suspect the investigators are hoping to design an anti-inflammatory supplement and make lots of money. I will stick with the fresh fruits and vegetables. 

Saturated fats are inflammatory. At face value, the data on saturated fats appear to be contradictory. Some Fatty Foodsstudies say that saturated fats increase inflammation, while others say they do not. However, similar to my earlier discussion on saturated fats and heart disease), the outcome of the study depends on what the saturated fats are replaced with.

When saturated fats are replaced with refined carbohydrates, sugar and highly processed foods (the standard American low-fat diet), inflammation doesn’t change. This doesn’t mean that a diet high in saturated fat is healthy. It just means that both diets are bad for you. Both are inflammatory.

However, when saturated fat is replaced with omega-3 polyunsaturated fats (J.A. Paniagua et al, Atherosclerosis, 218: 443-450, 2011) or monounsaturated fats (B. Vessby et al, Diabetologia, 44: 312-319, 2001), markers of inflammation decrease. Clearly, saturated fats are not the best fat choice if you wish to keep inflammation in check.

I would be remiss if I did not address the claims by the low-carb diet proponents that saturated fats do not increase inflammation in the context of a low-carb diet. I want to remind you of two things we have discussed previously:

  • The comparisons in those studies are generally with people consuming a diet high in simple carbohydrates and sugars.
  • These studies have mostly been done in the short-term when the participants are losing weight on the low-carb diets. Weight loss decreases inflammation, so the reduction in inflammation on the low-carb diet could be coming from the weight loss.

The one study (M. Miller et al, Journal of the American Dietetic Association, 109: 713-717, 2009) I have found that compares a low-carb diet (the Atkins diet) with a good diet (the Ornish diet, which is a low-fat, lacto-ovo vegetarian diet) during weight maintenance found that the meat based, low-carb Atkins diet caused greater inflammation than the healthy low-fat Ornish diet.

Red meat is probably pro-inflammatory. Most, but not all, studies suggest that red meat consumption is associated with increased inflammation. If it is pro-inflammatory, the inflammation is most likely associated with its saturated fat, its heme iron content, or the advanced glycation end products formed during cooking.

What Is An Anti-Inflammatory Diet?

Colorful fruits and vegetablesAnti-inflammatory diets have become so mainstream that they now appear on many reputable health organization websites such as Harvard Health, WebMD, the Mayo Clinic, and the Cleveland Clinic. Each have slightly different features, but there is a tremendous amount of agreement. 

Foods an anti-inflammatory diet includes: In a nutshell, an anti-inflammatory diet includes fruits and vegetables, whole grains, plant-based proteins (like beans and nuts), fatty fish, and fresh herbs and spices. Specifically, your diet should emphasize:

  • Colorful fruits and vegetables. Not only do they help fight inflammation, but they are a great source of antioxidants and other nutrients important for your health.
  • Whole grains. They have a low glycemic index. They are also a good source of fiber, and fiber helps flush inflammatory toxins out of the body.
  • Beans and other legumes. They should be your primary source of protein. They are high in fiber and contain antioxidants and other anti-inflammatory nutrients.
  • Nuts, olive oil, and avocados. They are good sources of healthy monounsaturated fats, which fight inflammation.
  • Fatty fish. Salmon, tuna, and sardines are all great sources of long chain omega-3 fatty acids, which are fish and fish oilincorporated into our cell membranes. Those long chain omega-3s in cell membranes are, in turn, used to create compounds that are powerful inflammation fighters.

Walnuts, flaxseeds, and chia seeds are good sources of short chain omega-3s. The efficiency of their conversion to long chain omega-3s that can be incorporated into cell membranes is only around 2-5%. If they fight inflammation, it is probably because they replace some of the saturated fats and omega-6 fats you might otherwise be eating.

  • Herbs and spices. They add antioxidants and other phytonutrients that fight inflammation.

Foods an anti-inflammatory diet excludes: In a nutshell, an anti-inflammatory diet should exclude highly processed, overly greasy, or super sweet foods, especially sodas and other sweet drinks. Specifically, your diet should exclude:

  • Refined carbohydrates, sodas and sugary foods. They have a high glycemic index, which is associated with inflammation. They can also lead to weight gain and high blood sugar, both of which cause inflammation.
  • Foods high in saturated fats. This includes fatty and processed meats, butter, and high fat dairy products.
  • Foods high in trans fats. This includes margarine, coffee creamers, and any processed food containing partly hydrogenated vegetable oils. Trans fats are very pro-inflammatory.
  • French fries, fried chicken, and other fried foods. They used to be fried in saturated fat and/or trans fat. Nowadays, they are generally fried in omega-6 vegetable oils. A little omega-6 in the diet is OK, but Americans get too much omega-6 fatty acids in their diet. Most studies show that a high ratio of omega-6 to omega-3 fatty acids is pro-inflammatory.
  • Foods you are allergic or sensitive to. Eating any food that you are sensitive to can cause inflammation. This comes up most often with respect to gluten and dairy because so many people are sensitive to one or both. However, if you are not sensitive to them, there is no reason to exclude whole grain gluten-containing foods or low-fat dairy foods from your diet.

Can Diet Douse The Flames?

FlamesIn case you didn’t notice, the recommendations for an anti-inflammatory diet closely match the other healthy diets I have discussed previously. It should come as no surprise then that both the Mediterranean (L. Gallard, Nutrition in Clinical Practice, 25: 634-640, 2010; L. Schwingshackl and G. Hoffmann, Nutrition Metabolism and Cardiovascular Diseases, 24: 929-939, 2014) and DASH (D.E. King et al, Archives of Internal Medicine, 167: 502-506, 2007) diets are anti-inflammatory.

Vegan and vegetarian diets also appear to be anti-inflammatory as well. The anti-inflammatory nature of these diets undoubtedly contributes to their association with a lower risk of heart disease, diabetes, and cancer.

As for the low-carb diets, the jury is out. There are no long-term studies to support the claims of low-carb proponents that their diets reduce inflammation. The few long-term studies that are available suggest that low-carb diets are only likely to be anti-inflammatory if vegetable proteins and oils replace the animal proteins and fats that are currently recommended.

What does this mean for you if you have severe arthritis or other inflammatory diseases? An anti-inflammatory diet is unlikely to “cure” your symptoms by itself. However, it should definitely be a companion to everything else you are doing to reduce inflammation.

The Bottom Line 

If you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It’s something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. In this article I review the evidence that certain foods influence inflammation and describe what an anti-inflammatory diet looks like.

For more details read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Can You Improve Your Healthspan?

Can You Live Healthier, Longer?

Ever since Ponce de Leon led an expedition to the Florida coast in 1513, we have been searching for the mythical “Fountain Of Youth”. What does that myth mean?

Supposedly, just by immersing yourself in that fountain you would be made younger. You would experience all the exuberance and health you enjoyed when you were young. There have been many snake oil remedies over the years that have promised that. They were all frauds.

But what if you had it in your power to live longer and to retain your youthful health for most of those extra years. The ability to live healthier longer is something that scientists call “healthspan”. But you can think of it as your personal “Fountain Of Youth”.

Where are we as a nation? Americans ranked 53rd in the world for life expectancy. We have the life expectancy of a third-world country. We are in sore need of a “Fountain Of Youth”.

That is why I decided to share two recent studies from the prestigious Harvard T.H. Chan School of Public Health with you today.

How Were The Studies Done?

Clinical StudyThese studies started by combining the data from two major clinical trials:

  • The Nurse’s Health Study, which ran from 1980 to 2014.
  • The Health Professional’s Follow-Up Study, which ran from 1986-2014.

These two clinical trials enrolled 78,865 women and 42,354 men and followed them for an average of 34 years. During this time there were 42,167 deaths. All the participants were free of heart disease, type 2 diabetes, and cancer at the time they were enrolled. Furthermore, the design of these clinical trials was extraordinary.

  • A detailed food frequency questionnaire was administered every 2-4 years. This allowed the investigators to calculate cumulative averages of all dietary variables.
  • Participants also filled out questionnaires that captured information on disease diagnosis every 2 years with follow-up rates >90%. This allowed the investigators to measure the onset of disease for each participant during the study. More importantly, 34 years is long enough to measure the onset of diseases like heart disease, diabetes, and cancer – diseases that require decades to develop.
  • The questionnaires also captured information on medicines taken and lifestyle characteristics such as body weight, exercise, smoking and alcohol use.
  • For analysis of diet quality, the investigators use something called the “Alternative Healthy Eating Index”. [The original Healthy Eating Index was developed about 10 years ago based on the 2010 “Dietary Guidelines for Americans”. Those guidelines have since been updated, and the “Alternative Healthy Eating Index” is based on the updated guidelines.] You can calculate your own Alternative Healthy Eating Index below, so you can see what is involved.
  • Finally, the investigators included five lifestyle-related factors – diet, smoking, physical activity, alcohol consumption, and BMI (a measure of obesity) – in their estimation of a healthy lifestyle. Based on the best available evidence, they defined “low-risk” in each of these categories. Study participants were assigned 1 point for each low-risk category they achieved. Simply put, if they were low risk in all 5 categories, they received a score of 5. If they were low risk in none of the categories, they received a score of 0.
  • Low risk for each of these categories was defined as follows:
    • Low risk for a healthy diet was defined as those who scored in the top 40% in the Alternative Healthy Eating Index.
    • Low risk for smoking was defined as never smoking.
    • Low risk for physical activity was defined as 30 minutes/day of moderate or vigorous activities.
    • Low risk for alcohol was defined as 0.5-1 drinks/day for women and 0.5-2 drinks/day for men.
    • Low risk for weight was defined as a BMI in the healthy range (18.5-24.9 kg/m2).

Can You Live Healthier Longer?

Older Couple Running Along BeachThe investigators compared participants who scored as low risk in all 5 categories with participants who scored as low risk in 0 categories (which would be typical for many Americans). For the purpose of simplicity, I will refer to people who scored as low risk in 5 categories as having a “healthy lifestyle” and those who scored as low risk in 0 categories as having an “unhealthy lifestyle”.

The results of the first study were:

  • Women who had had a healthy lifestyle lived 14 years longer than women with an unhealthy lifestyle (estimated life expectancy of 93 versus 79).
  • Men who had a healthy lifestyle lived 12 years longer than men with an unhealthy lifestyle (estimated life expectancy was 87 versus 75).
  • It was not necessary to achieve a perfect lifestyle. Life expectancy increased in a linear fashion for each low-risk lifestyle behavior achieved.

The authors of the study concluded: “Adopting a healthy lifestyle could substantially reduce premature mortality and prolong life expectancy in US adults. Our findings suggest that the gap in life expectancy between the US and other developed countries could be narrowed by improving lifestyle factors.”

The results of the second study were:

  • Women who had a healthy lifestyle lived 11 years longer free of diabetes, heart disease, and cancer than women who had an unhealthy lifestyle (estimated disease-free life expectancy of 85 years versus 74 years).
  • Men who had a healthy lifestyle lived 8 years longer free of diabetes, heart disease, and cancer than men who had an unhealthy lifestyle (estimated disease-free life expectancy of 81 years versus 73 years).
  • Again, disease-free life expectancy increased in a linear fashion for each low-risk lifestyle behavior achieved.

The authors concluded: “Adherence to a healthy lifestyle at mid-life [They started their analysis at age 50] is associated with a longer life expectancy free of major chronic diseases. Our findings suggest that promotion of a healthy lifestyle would help reduce healthcare burdens through lowering the risk of developing multiple chronic diseases, including cancer, cardiovascular disease, and diabetes, and extending disease-free life expectancy.”

Can You Improve Your Healthspan?

Questioning ManI posed the question at the beginning of this article, “Can you improve your healthspan?” These two studies showed that you can improve both your life expectancy and your disease-free life expectancy. So, the answer to the original question appears to be, “Yes, you can improve your healthspan. You can create your personal “Fountain of Youth.”

However, as a nation we appear to be moving in the wrong direction. The percentage of US adults adhering to a healthy lifestyle has decreased from 15% in 1988-1992 to 8% in 2001-2006.

The clinical trials that these studies drew their data from were very well designed, so these are strong studies. However, like all scientific studies, they have some weaknesses, namely:

  • They looked at the association of a healthy lifestyle with life expectancy and disease-free life expectancy. Like all association studies, they cannot prove cause and effect.
  • The clinical trials they drew their data with included mostly Caucasian health professionals. The results may differ with different ethnic groups.
  • These studies did not look at the effect of a healthy lifestyle on the onset of Alzheimer’s disease and other forms of dementia. However, other studies have shown that people who were low risk for each of the 5 lifestyle factors (diet, exercise, body weight, smoking, and alcohol use) individually have a reduced risk of developing Alzheimer’s and/or dementia.

Finally, I know you have some questions, and I have answers.

Question: What about supplementation? Will it also improve my healthspan?

Answer: When the investigators analyzed the data, they found that those with the healthiest lifestyles were also more likely to be taking a multivitamin. So, they attempted to statistically eliminate any effect of supplement use on the outcomes. That means these studies cannot answer that question.

However, if you calculate your Alternate Healthy Eating Index below, you will see that most of us fall short of perfection. Supplementation can fill in the gaps.

Question: I cannot imagine myself reaching perfection in all 5 lifestyle categories? Should I even try to achieve low risk in one or two categories?

Answer: The good news is that there was a linear increase in both life expectancy and disease-free life expectancy as people went from low-risk in one category to low-risk in all 5 categories. I would encourage you to try and achieve low risk status in as many categories as possible, but very few of us, including me, achieve perfection in all 5 categories.

Question: I am past 50 already. Is it too late for me to improve my healthspan?

Answer: Diet and some of the other lifestyle behaviors were remarkably constant over 34 years in both the Nurse’s Health Study and the Health Professional’s Follow-Up Study. That means that the lifespan and healthspan benefits reported in these studies probably resulted from adhering to a healthy lifestyle for most of their adult years.

However, it is never too late to start improving your lifestyle. You may not achieve the full benefits described in these studies, but you still can add years and disease-free years to your life.

How To Calculate Your Alternative Healthy Eating Index

You can calculate your own Alternative Healthy Eating Index score by simply adding up the points you score for each food category below.

Vegetables

Count 2 points for each serving you eat per day (up to 5 servings).

One serving = 1 cup green leafy vegetables or ½ cup for all other vegetables.

Do not count white potatoes or processed vegetables like French fries or kale chips.

Fruits

Count 2½ points for each serving you eat per day (up to 4 servings).

One serving = 1 piece of fruit or ½ cup of berries.

          (do not count fruit juice or fruit incorporated into desserts or pastries). 

Whole Grains

Count 2 points for each serving you eat per day (up to 5 servings).

One serving = ½ cup whole-grain rice, bulgur and other whole grains, cereal, and pasta or 1 slice of bread.

(For processed foods like pasta and bread, the label must say 100% whole grain).

Sugary Drinks and Fruit Juice

Count 10 points if you drink 0 servings per week.

Count 5 points for 3-4 servings per week (½ serving per day).

Count 0 points for 7 or more servings per week (≥1 serving per day).

One serving = 8 oz. fruit juice, sugary soda, sweetened tea, coffee drink, energy drink, or sports drink.

Nuts, Seeds and Beans

Count 10 points if you eat 7 or more servings per week (≥1 serving per day).

Count 5 points for 3-4 servings per week (½ serving per day).

Count 0 points for 0 servings per week.

One serving = 1 oz. nuts or seeds, 1 Tbs. peanut butter, ½ cup beans, 3½ oz. tofu.

Red and Processed Meat

Count 10 points if you eat 0 servings per week.

Count 7 points for 3-4 servings per week (½ serving per day).

Count 3 points for 3 servings per week (1 serving per day).

Count 0 points for ≥1½ servings per day.

One serving = 1½ oz. processed meats (bacon, ham, sausage, hot dogs, deli meat)

          Or 4 oz. red meat (steak, hamburger, pork chops, lamb chops, etc.)

Seafood

Count 10 points if you eat 2 servings per week.

Count 5 points for 1 serving per week.

Count 0 points for 0 servings per week.

1 serving = 4 oz.

Now that you have your total, the scoring system is:

  • 41 or higher is excellent
  • 37-40 is good
  • 33-36 is average (remember that it is average to be sick in this country)
  • 28-32 is below average
  • Below 28 is poor

Finally, for the purposes of these two studies, a score of 37 or higher was considered low risk.

The Bottom Line

Two recent studies have developed a healthy lifestyle score based on diet, exercise, body weight, smoking, and alcohol use. When they compared the effect of lifestyle on both lifespan (life expectancy) and healthspan (disease-free life expectancy), they reported:

  • Women who had had a healthy lifestyle lived 14 years longer than women with an unhealthy lifestyle.
  • Men who had a healthy lifestyle lived 12 years longer than men with an unhealthy lifestyle.
  • Women who had a healthy lifestyle lived 11 years longer free of diabetes, heart disease, and cancer than women had an unhealthy lifestyle.
  • Men who had a healthy lifestyle lived 8 years longer free of diabetes, heart disease, and cancer than men who had an unhealthy lifestyle.
  • It is not necessary to achieve a perfect lifestyle. Lifespan and healthspan increased in a linear fashion for each low-risk lifestyle behavior (diet, exercise, body weight, smoking, and alcohol use) achieved.
  • These studies did not evaluate whether supplement use also affects healthspan.
    • However, if you calculate your diet with the Alternate Healthy Eating Index they use (see above), you will see that most of us fall short of perfection. Supplementation can fill in the gaps.

The authors concluded: “Our findings suggest that promotion of a healthy lifestyle would help reduce healthcare burdens through lowering the risk of developing multiple chronic diseases, including cancer, cardiovascular disease, and diabetes, and extending disease-free life expectancy.”

For more details, including how to calculate whether you are low risk in each of the 5 lifestyle categories, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Diet And Cancer Risk

What Can You Do To Reduce Your Risk Of Cancer?

Magic WandIt seems like everyone has a magic pill, essential oil, food, or diet that prevents cancer. It doesn’t take a genius to figure out that all the claims can’t be true. No wonder you are confused. You want to know:

  • Which of these claims are true?
  • What can you do to reduce your risk of cancer?

These aren’t trivial questions.

  • Cancer is the second leading cause of death in this country, and some experts predict it will surpass heart disease as the leading cause of death in the near future.
  • While cancer treatments have become much more effective in the past few decades, these treatment successes are often associated with severe side-effects, enormous expense, or both.

That is why I was intrigued by a recent study (FF Zhang et al, JNCI Cancer Spectrum (2019) 3(2): pkz034) on diet and cancer that came from the prestigious Friedman School of Nutrition and Public Policy at Tufts University. This study asked two important questions:

  • How many newly diagnosed cancer cases could have been prevented by changes in the American diet? This is something the authors referred to as the “preventable cancer burden associated with poor diet”.
  • Which foods increased or decreased the risk of cancer? This, of course, is the most useful information for you and me.

Diet And Cancer Risk

Diet And CancerThis study estimated that 80,110 new cancer cases among US adults 20 and older could be primarily attributed to poor diet. While poor diet contributes to many more cancers, the authors of this study felt 80,110 represented the number of cancer cases that were clearly preventable by some simple dietary changes.

While all cancers were affected by diet to some degree, the cancers most affected by poor diet were:

  • Colon cancer (65% of cases)
  • Mouth and throat cancer (18% of cases)
  • Endometrial cancer (4.0% of cases)
  • Breast cancer (3.8% of cases)

When the diet was broken down into individual food groups:

  • Low intake of whole grains was associated with the largest number of preventable cancer cases (35% of cases). This was followed by.
  • Low intake of dairy foods (22% of cases).
  • High intake of processed meats (18% of cases).
  • Low intake of vegetables (16% of cases).
  • Low intake of fruits (10% of cases).
  • High intake of red meat (7.1% of cases).
  • High intake of sugar sweetened beverages (4.0% of cases).

Of the diet-associated cancer cases, the scientists who lead the study estimated that 84% of them represented a direct effect of diet on cancer risk. The dietary factors most likely to directly increase the risk of cancer were:

  • Low intake of whole grains.
  • Low intake of dairy foods.
  • High intake of processed meats.

The scientists estimated that 16% of diet-associated cancer cases were “mediated by obesity”. In layman’s terms, this means that diet increased the risk of obesity and obesity increased the risk of cancer. The dietary factors most likely to increase the risk of obesity-mediated cancers were:

  • High intake of sugar sweetened beverages.
  • Low intake of fruits.

The authors concluded: “More than 80,000 new cancer cases [per year] are estimated to be associated with suboptimal diet among US adults…Our findings underscore the need for reducing cancer burden in the United States by improving the intake of key food groups and nutrients of Americans.”

What Does This Mean For You?

Questioning ManThese findings aren’t novel. Many previous studies have come to the same conclusions. However, many people find these recommendations to be confusing. Should they increase their intake of certain foods? Should they follow some sort of magic diet?

Perhaps we need to get away from the magic food concept. We need to understand that every time we increase one food in our diet, we exclude other foods. We need to step back and look at the overall diet.

Let me break down the recommendations from this study into three categories: foods we should eliminate from our diet, foods we should include in our diet, and foods we should balance in our diet.

Foods we should eliminate from our diet:

  • Sugar Sweetened Beverages. They provide no nutritional benefit, and the sugar in most beverages rushes into our bloodstream and overwhelms our body’s ability to utilize it in a healthy way. This leads to obesity, diabetes, and a host of other health issues.
    • Public enemy number one is sodas. However, this category also includes fruit juices, sweetened teas and energy drinks, and sugary processed foods.
    • This category also includes diet sodas. For reasons we don’t completely understand, diet sodas appear to be just as likely to lead to obesity, diabetes, and heart disease as sugar sweetened sodas. I have discussed the proposed explanations of this phenomenon in a recent issue of “Health Tips From the Professor”.
    • Sugar, however, is not the enemy. Sugar found naturally in fruits and other whole foods enters the bloodstream slowly and is metabolized in healthy ways by the body. I have discussed this in another issue  of “Health Tips From the Professor”. This is what I mean by restoring balance in our diet. Decreasing the sugar intake from sugar sweetened beverages and increasing sugar intake from fruits is associated with a decreased risk of obesity and obesity-related cancers.
  • Processed Meats. The evidence is overwhelming at this point that processed meats directly increase the risk of cancer.
    • If you have trouble completely eliminating processed meats from your diet, my advice is to minimize them and consume them only in the context of an overall healthy diet. Personally, I still consume bacon occasionally as flavoring for a healthy green salad.

Whole GrainsFoods we should include in our diet. I put these in a separate category because Dr. Strangelove and his colleagues have been telling us to eliminate them from our diet, and many Americans are following those recommendations:

  • Whole grains. We can think of whole grains as the underserving victim of the low-carb craze. The low-carb craze is on the mark when it comes to eliminating added sugars and refined grains from the diet. However, eliminating whole grains from the diet may be doing more harm than good. In fact, this and other studies suggest that whole grains are the most effective foods for reducing cancer risk. Why is that?
    • If we assume whole grains are just a good source of fiber and a few vitamins and minerals, it is hard to grasp their importance. We could easily get those nutrients elsewhere.
    • However, we are beginning to realize that whole grains play a unique role in supporting certain species of gut bacteria that are very beneficial to our health. In short, whole grains may be essential for a healthy gut.
  • Dairy Foods. This is another food that has been treated as a villain by Dr. Strangelove and his many colleagues. However, for reasons we don’t completely understand, dairy foods appear to decrease the risk of heart disease and cancer.

Foods we should balance in our diet.

  • Red Meat. Diets high in red meat are consistently associated with a slight increase in cancer risk. The World Health Organization lists red meat as a probable carcinogen, but that has proven to be controversial.
    • Much of the research has centered on why red meat causes cancer. Several mechanisms have been proposed, but none of them have been proven.
    • In contrast, very little consideration has been given to what red meat is displacing from the diet. Diets high in red meat are often low in whole grains, fruits and/or vegetables.
    • Perhaps instead of eliminating red meat from our diets we should be talking about balancing red meat in our diets by consuming less red meat and more whole grains, fruits, and vegetables.

What Can You Do To Reduce Cancer Risk?

American Cancer SocietyYou may have been thinking that 80,110 cases/year represents a small percentage of new cancer cases. That’s because diet is only one component of a holistic cancer prevention strategy. Here is what the American Cancer Society recommends for reducing cancer risk:

  • Avoid tobacco.
  • Limit sun exposure.
  • Achieve and maintain a healthy weight.
  • Eat a healthy diet, with an emphasis on plant foods (Their recommendations are in line with this study).
  • Be physically active.
  • Limit alcohol use.
  • Get vaccinated against HPV.
  • Get regular medical checkups.

Doing any of these things will reduce your cancer risk. But the more of these you can incorporate into your lifestyle, the lower your risk.

The Bottom Line

A recent study looked at diet and cancer risk. The authors reported that 80,110 new cancer cases among US adults 20 and older could be primarily attributed to poor diet.

When the diet was broken down into individual food groups:

  • Low intake of whole grains was associated with the largest number of preventable cancer cases. This was followed in descending order by.
  • Low intake of dairy foods.
  • High intake of processed meats.
  • Low intake of vegetables.
  • Low intake of fruits.
  • High intake of red meat.
  • High intake of sugar sweetened beverages.

The authors concluded: “More than 80,000 new cancer cases [per year] are estimated to be associated with suboptimal diet among US adults…Our findings underscore the need for reducing cancer burden in the United States by improving the intake of key food groups and nutrients of Americans.”

For more details, read the article above. For example, I discuss which foods we should eliminate, which foods we should eat more of, and which foods we should balance in our diet. To add a more holistic perspective, I also discuss the American Cancer Society’s recommendations for reducing cancer risk.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Health Tips From The Professor