Does Olive Oil Help You Live Longer?

Which Fat Is Healthiest?

Author: Dr. Stephen Chaney

If you believe the headlines, olive oil is a superfood. It is often described as the star of the Mediterranean diet. It is referred to as the healthiest of dietary fats. Is this true, or is it hype?

Olive oil’s resume is impressive:

  • It is rich in monounsaturated fatty acids, which…
    • Are less susceptible to oxidation than polyunsaturated oils.
    • Make our arteries more flexible, which lowers blood pressure.
    • Lower LDL-cholesterol levels, which reduces the risk of heart disease.
  • Extra-virgin olive oil contains phytonutrients and tocopherols (various forms of vitamin E), which…
    • Have anti-inflammatory properties.
    • Improve insulin sensitivity and blood sugar control.
  • Olive oil consumption is also associated with healthier gut bacteria, but it is not clear whether this is due to olive oil or to the fact that a Mediterranean diet is also richer in fresh fruits, vegetables, and whole grains.

Several recent studies have shown that olive oil consumption is associated with a lower risk of heart disease. However, these studies were conducted in Mediterranean countries where the average intake of olive oil (3 tablespoons/day) is much greater than in the United States (0.3 tablespoons/day).

The current study (M Guasch-Ferré et al, Journal of the American College of Cardiology, 79: 101-112, 2022) was designed to test whether:

  • The amount of olive oil Americans consume decreases the risk of heart disease.
  • Whether olive oil consumption had benefits beyond a reduction in heart disease risk.

How Was This Study Done? 

Clinical StudyThis study combined data from 60,582 women enrolled in the Nurses’ Health Study and 31,801 men enrolled in the Health Professionals Follow-Up Study). The participants:

  • Were free of heart disease and diabetes at the start of the study.
  • Were 56 at the start of the study with an average BMI of 25.6 (Individuals with BMIs in the 25-30 range are considered overweight, so they were at the lowest end of the overweight range).

The Nurses’ Health Study and Health Professional Follow-Up Study are both association studies, meaning they looked at the association between olive oil consumption and health outcomes. They cannot directly prove cause and effect. However, they are very strong association studies because:

  • Every 2 years, participants filled out a questionnaire that updated information on their body weight, smoking status, physical activity, medications, multivitamin use, and physician-diagnosed diseases.
  • Every 4 years, participants filled out a comprehensive food frequency questionnaire.
  • In other words, this study did not just rely on the participant’s lifestyle, dietary intake, and health at the beginning of the study, as so many association studies do. It tracked how each of these variables changed over time.

The participants were followed for an average of 28 years and their average olive oil intake over those 28 years was correlated with all-cause mortality and mortality due to specific diseases.

  • Deaths were identified from state vital statistics, the National Death index, reports by next of kin, or reports by postal authorities.
  • Causes of death were determined by physician review of medical records, medical reports, autopsy reports, or death certificates.

Does Olive Oil Help You Live Longer?

During the 28 years of this study:

  • Olive oil consumption in the United States increased from an average of ~1/3 teaspoon/day to ~1/3 tablespoon/day.
  • Margarine consumption decreased from 12 g/day to ~4 g/day.
  • The consumption of all other fats and oils remained about the same.

As I mentioned above, olive oil consumption was averaged over the life of the study for each individual. When the investigators compared people consuming the highest amount of olive oil (>0.5 tablespoon/day) with people consuming the least olive oil (0 to 1 teaspoon/day):

  • Mortality from all causes was decreased by 35% for the group consuming the most olive oil.

However, the group consuming the most olive oil also was more physically active, had a healthier diet, and consumed more fruits and vegetables than the group who consumed the least olive oil.

  • After correcting for all those factors, mortality from all causes was decreased by 19% for the group consuming the most olive oil.

The authors concluded, “We found that greater consumption of olive oil was associated with lower risk of total…mortality… Our results support current dietary recommendations to increase the intake of olive oil…to improve overall health and longevity.” (I will fill in the blanks in this statement once I have covered other aspects of this study)

The authors also said, “Of note, our study showed that benefits of olive oil can be observed even when consumed in lower amounts than in Mediterranean countries.”

Are There Other Benefits From Olive Oil Consumption?

Mediterranean dietThe study didn’t stop there. The investigators also looked at the effect of olive oil consumption on the major killer diseases in the United States and other developed countries. When they compared the effect of olive oil consumption on cause-specific mortality, they found that the group who consumed the most olive oil reduced their risk of dying from:

  • Cardiovascular disease by 19%.
  • Cancer by 17%
  • Respiratory disease by 18%.
  • Neurodegenerative disease (cognitive decline and Alzheimer’s disease) by 29%.
    • The reduction in neurodegenerative disease was much greater for women (34% decrease) than for men (19% decrease).

With this information I can fill in one of the blanks in the author’s conclusions: “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality… Our results support current dietary recommendations to increase the intake of olive oil…to improve overall health and longevity.”

Which Fats Are Healthiest?

Good Fat vs Bad FatThe sample size was large enough and the dietary information complete enough for the investigators to also estimate the effect of substituting olive oil for other dietary fats and oils.

They found that every ¾ tablespoon of olive oil substituted for an equivalent amount of:

  • Margarine decreased total mortality by 13%.
  • Butter decreased total mortality by 14%.
  • Mayonnaise deceased total mortality by 19%
  • Dairy fat decreased total mortality by 13%.
    • The same beneficial effects of substituting olive oil for other fats were seen for cause-specific mortality (cardiovascular disease, cancer, respiratory disease, and neurodegenerative disease).
    • There was a linear dose-response. This means that substituting twice as much olive oil for other dietary fats doubled the beneficial effects on total and cause-specific mortality.
  • However, substituting olive oil for polyunsaturated vegetable oils had no effect on total and cause-specific mortality.

Now I can fill in the remaining blanks in the author’s conclusion: “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality. Replacing other types of fat, such as margarine, butter, mayonnaise, and dairy fat, with olive oil was also associated with a lower risk of mortality. Our results support current dietary recommendations to increase the intake of olive oil and other unsaturated vegetable oils in place of other fats to improve overall health and longevity.”

What Does This Study Mean For Us?

ConfusionAs I said above, this is an association study, and association studies do not prove cause and effect. However:

1) This is a very strong association study because:

    • It is a very large study (92,383 participants).
    • It followed the participants over a long time (28 years).
    • It utilized a very precise dietary analysis.
    • Most importantly, it tracked the participant’s lifestyle, dietary intake, and health at regular intervals throughout the study. Most association studies only measure these variables at the beginning of the study. They have no idea how they change over time.

2) This study is consistent with several previous studies showing that olive oil consumption decreases the risk of dying from heart disease.

3) This study draws on its large population size and precise dietary analysis to strengthen and extend the previous studies. For example:

    • The study showed that increased olive oil consumption also reduced total mortality and mortality due to cancer, respiratory disease, and neurodegenerative disease.
    • The study measured the effect of substituting olive oil for other common dietary fats.
    • The study showed that increased olive oil consumption in the context of the American diet was beneficial.

I should point out that the headlines you have seen about this study may be misleading.

  • While the headlines may have depicted olive oil as a superfood, this study did not find evidence that olive oil was more beneficial than other unsaturated vegetable oils. Again, this is consistent with many previous studies showing that substituting vegetable oils for other dietary fats reduces the risk of multiple diseases.
  • The headlines focused on the benefits of increasing olive oil consumption. However, they neglected the data showing that increasing olive oil (and other vegetable oils) was even more beneficial (35% reduction in total mortality) in the context of a healthy diet – one with increased intake of fruits, vegetables, whole grains, nuts, legumes, and long-chain omega-3s and decreased intake of red & processed meats, sodium, and trans fats.

So, my recommendation is to follow a whole food, primarily plant-based diet and substitute extra-virgin olive oil and cold pressed vegetable oils for some of the animal fats in your diet.

Some vegan enthusiasts recommend a very low-fat whole food plant-based diet. They point to studies showing that such diets can actually reverse atherosclerosis. However:

  • Those studies are very small.
  • The overall diet used in those studies is a very healthy plant-based diet.
  • The studies did not include a control group following the same diet with olive oil or other vegetable oils added to it, so there is no comparison of a healthy vegan diet with and without vegetable oils.

If you have read my book, Slaying the Food Myths, you know that my recommendations encompass a variety of whole food, primarily plant-based diets ranging all the way from very-low fat vegan diets to Mediterranean and DASH diets. Choose the one that best fits your food preferences and the one you will be most able to stick with long term. You will be healthier, and you may live longer.

The Bottom Line

A recent study looked at the effect of olive oil consumption on the risk dying from all causes and from heart disease, cancer, respiratory disease, and neurodegenerative diseases. When the study compared people consuming the highest amount of olive oil (>0.5 tablespoon/day) with people consuming the least olive oil (0 to 1 teaspoon/day):

  • Mortality from all causes was decreased by 19% for the group consuming the most olive oil.

They also found that the group who consumed the most olive oil reduced their risk of dying from:

  • Cardiovascular disease by 19%.
  • Cancer by 17%
  • Respiratory disease by 18%.
  • Neurodegenerative disease (cognitive decline and Alzheimer’s disease) by 29%.

They also found that every ¾ tablespoon of olive oil substituted for an equivalent amount of:

  • Margarine decreased total mortality by 13%.
  • Butter decreased total mortality by 14%.
  • Mayonnaise deceased total mortality by 19%
  • Dairy fat decreased total mortality by 13%.
  • However, substituting olive oil for polyunsaturated vegetable oils had no effect on total and cause-specific mortality.

The authors concluded, “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality. Replacing other types of fat, such as margarine, butter, mayonnaise, and dairy fat, with olive oil was also associated with a lower risk of mortality. Our results support current dietary recommendations to increase the intake of olive oil and other unsaturated vegetable oils in place of other fats to improve overall health and longevity.”

For more details and a summary of what this study 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.

Can Your Diet Cause You To Lose Your Mind?

What Is A Mind-Healthy Lifestyle? 

Author: Dr. Stephen Chaney

Cognitive-DeclineMost of us look forward to our golden years – that mystical time when we will be free from the workday pressures and have more time to spend with friends and family doing the things we love.

But cognitive decline can cast a dark cloud over those expectations.

  • By the age of 65, 11% of adults suffer from some degree of cognitive impairment.
  • And by the age of 80 the percentage of adults suffering from cognitive impairment has increased to 26-30%, depending on which study you cite.

The results of cognitive decline can be devastating.

  • First you start to lose the cherished memories of a lifetime.
  • Then comes confusion and an inability to perform basic tasks and participate in your favorite activities.
  • Eventually you may reach a stage where you no longer recognize the ones you love.

In short, cognitive decline can rob you of everything that makes you you.

The causes of cognitive decline are complex, but recent studies have pointed to the role of chronic inflammation in cognitive decline. If that is true, it is a good news – bad news situation.

  • The bad news is:
    • Some increase in chronic inflammation appears to be an inevitable consequence of aging.
    • Chronic inflammation can be caused by certain diseases that are beyond our control.
    • Chronic inflammation can be triggered by viral or bacterial infections.
  • The good news is that chronic inflammation is also controlled by your diet and lifestyle. For example, as I said above, chronic inflammation is often triggered by a viral infection, but whether the inflammation is mild or severe is strongly influenced by diet and lifestyle.

In this issue of “Health Tips From the Professor” I share a study (S Charisis et al, Neurology, In Press, November 10, 2021) showing that diets high in inflammatory foods increase the risk of dementia. Then, I answer 3 important questions.

  • Can your diet cause you to lose your mind?
  • What is a mind-healthy diet?
  • What is a mind-healthy lifestyle?

How Was This Study Done?

Clinical StudyThe data for this study were taken from the first three years of the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD), a study designed to look at the effect of diet on dementia and other neuropsychiatric conditions in the Greek population.

There were 1059 participants (40% male, average age = 75 at the beginning of the study) in this study. At the beginning of the study the participants completed a food frequency questionnaire administered by a trained dietitian. The foods were broken down into individual nutrients using the USDA Food Composition tables adapted for foods in the Greek diet.

The diet of each participant was then rated on a 15-point scale ranging from pro-inflammatory to anti-inflammatory based on something called the Diet Inflammation Index (DII).

Simply put, the DII is a validated assessment tool based on the effect of food nutrients on 6 inflammatory biomarkers found in the blood (IL-1β, IL-4, IL-6, IL-10, TNF-α, and CRP). Nutrients that decrease these markers are considered anti-inflammatory. Nutrients that increase these inflammatory biomarkers are considered pro-inflammatory.

For example, anti-inflammatory nutrients include:

  • Carotenoids and flavonoids (found in fruits and vegetables).
  • Omega-3 polyunsaturated fatty acids (found in cold-water fish, walnuts, flaxseeds, and chia seeds).
  • Monounsaturated fatty acids (found in olive, avocado, and peanut oils).
  • Fiber (found in minimally processed plant foods).
  • Antioxidants, most B vitamins, and vitamin D.
  • Magnesium and zinc.
  • Garlic, onions, most herbs & spices.

Pro-inflammatory nutrients include:

  • Refined carbohydrates.
  • Cholesterol.
  • Total fat.
  • Saturated fats.
  • Trans fats.

The participants were followed for 3 years, and all new diagnoses of dementia were recorded. The diagnoses were confirmed by a panel of neurologists and neuropsychologists.

Can Your Diet Cause You To Lose Your Mind?

Forgetful Old ManAs described above, the diet of each participant in the study was rated on a 15-point DII (Diet Inflammatory Index) scale ranging from pro-inflammatory to anti-inflammatory. The association of the DII score of the participant’s diets with the onset of dementia was evaluated in two ways.

  • Each one-point increase from an anti-inflammatory diet to a pro-inflammatory diet was associated with a 21% increase in the risk for dementia.
  • In other words, even small changes in your diet can have a significant impact on your risk of developing dementia.

The investigators then divided the participants into three equal-sized groups based on the DII score of their diets.

  • The group with the highest DII scores were 3 times more likely to develop dementia than the group with the lowest DII scores.
  • In other words, a major change in your diet can have a major effect on your risk of developing dementia.

The authors concluded, “In the present study, higher DII scores (indicating greater pro-inflammatory diet potential) were associated with an increased risk for incident dementia [newly diagnosed dementia]. These findings may avail the development of primary dementia strategies through tailored and precise dietary interventions.”

What Is A Mind-Healthy Diet?

Vegan FoodsThis and other studies show that an anti-inflammatory diet is good for the mind. It helps protect us from cognitive decline and dementia. But what does an anti-inflammatory diet look like?

One hint comes from analyzing the diets of participants in this study:

  • Those with the lowest DII scores (most-anti-inflammatory diets) consumed 20 servings of fruit, 19 servings of vegetables, 4 servings of beans or other legumes, and 11 servings of coffee or tea each week. That’s almost 3 servings of fruit and 3 servings of vegetables every day!
  • Those with the highest DII scores (most pro-inflammatory diets) consumed only half as many fruits, vegetables, and legumes.
  • In short, a diet rich in fruits, vegetables, and legumes is a good start.

I have described anti-inflammatory diets in more detail in a previous issue of “Health Tips From the Professor.” Let me summarize that article briefly.

Anti-inflammatory foods include:

  • Colorful fruits and vegetables.
  • Whole grains.
  • Beans and other legumes.
  • Nuts, olive oil, avocados, and other sources of monounsaturated fats.
  • Fatty fish and other sources of omega-3 fatty acids.
  • Herbs and spices.

Pro-inflammatory foods include:

  • Refined carbohydrates, sodas, and sugary foods.
  • Foods high in saturated fats including fatty and processed meats, butter, and high fat dairy products.
  • Foods high in trans fats.
  • French fries, fried chicken, and other fried foods.
  • Foods you are allergic or sensitive food. For example, gluten containing foods are pro-inflammatory only if you are sensitive to gluten.

If your goal is to reduce chronic inflammation and keep your mind sharp as a tack as you age, you should eat more anti-inflammatory foods and less pro-inflammatory foods.

Of course, we don’t just eat random foods, we follow dietary patterns. It should be apparent from what I have Mediterranean Diet Foodscovered above that whole food, primarily plant-based diets are anti-inflammatory. This is true for diets ranging from vegan through semi-vegetarian, to the Mediterranean, DASH, and MIND diets.

All these diets are anti-inflammatory and likely protect the brain from cognitive decline. However, the best evidence for brain protection is for the Mediterranean, DASH, and MIND diets.

  • The Mediterranean and DASH diets have been shown to prevent cognitive decline in multiple studies.
  • The MIND diet is a combination the Mediterranean and DASH diets that was specifically designed to prevent cognitive decline. It has been shown to cut the risk of developing Alzheimer’s disease in half.

What Is A Mind-Healthy Lifestyle?

Diet is just one aspect of a holistic approach for reducing cognitive decline as we age. Other important factors include:

  • Reduce excess body weight.
  • Exercise regularly.
  • Get adequate sleep.
  • Reduce and/or manage stress.
  • Eliminate smoking and reduce alcohol consumption.
  • Socialize with friends and family who support you. Numerous studies have shown that a strong support network reduces dementia risk in the elderly.
  • Keep your brain active. Work crossword puzzles. Learn new things. An active brain is forced to lay down new neural pathways.

The Bottom Line 

Recent studies have suggested that chronic inflammation increases the risk of cognitive decline and dementia as we age. Some causes of chronic inflammation are beyond our control, but others, such as diet, we can control.

Recently, a precise scoring system called the Diet Inflammatory Index (DII) has been developed. This scoring system allows studies to look at the correlation between the inflammatory potential of the diet and cognitive decline.

A recent study enrolled 1,000 participants with an average age of 75 in a 3-year study to determine the impact of diet on cognitive decline. The association of the DII score of the participant’s diets with the onset of dementia was evaluated in two ways.

  • Each one-point increase from an anti-inflammatory diet to a pro-inflammatory diet was associated with a 21% increase in the risk for dementia.
  • In other words, even small changes in your diet can have a significant impact on your risk of developing dementia.

The investigators then divided the participants into three equal-sized groups based on the DII score of their diets.

  • The group with the highest DII scores were 3 times more likely to develop dementia than the group with the lowest DII scores.
  • In other words, a major change in your diet can have a major effect on your risk of developing dementia.

The authors concluded, “In the present study, higher DII scores (indicating greater pro-inflammatory diet potential) were associated with an increased risk for incident dementia [newly diagnosed dementia]. These findings may avail the development of primary dementia strategies through tailored and precise dietary interventions.”

For more details and a description of mind-healthy diets and a mind-healthy lifestyle 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.

Do Supplements Interfere With Chemotherapy?

Should You Avoid Supplement Use During Chemotherapy?

cancerSince much of my research career was devoted to cancer research, specifically developing new chemotherapeutic drugs for treating cancer, many of you have asked me the question: “Do food supplements interfere with chemotherapy?”

My answer has always been that it is theoretically possible, but that we don’t really know the answer because the necessary studies have not been done.

However, I do know that most cancer drugs are retained in the body for a short period of time. So, my pragmatic advice has always been to avoid supplementation for a day or two before to a day or two after each round of chemotherapy. That is a strategy designed to minimize the possibility that supplementation would interfere with chemotherapy and maximize the possibility that supplementation might aid in recovery between rounds of chemotherapy.

That is why I was interested when I saw the recent headlines claiming certain supplements may interfere with chemotherapy for breast cancer. I wanted to find out if someone had finally done a definitive study on the effect of supplementation on chemotherapy.

So, I have reviewed the study (CB Ambrosone et al, Journal of Clinical Oncology, 38, 804-815, 2020) behind the headlines and will share what I discovered.

How Was The Study Done?

Clinical StudyThis study was an offshoot of a much larger Phase III clinical trial designed to determine the best schedule for administering three drugs (doxorubicin, cyclophosphamide, and paclitaxel) to patients with high-risk early-stage breast cancer.

The 1,134 patients enrolled in this study were given questionnaires on their use of supplements when they registered for the study to determine supplement use prior to the study. They were also given questionnaires when they completed chemotherapy to determine supplement use during chemotherapy.

The questionnaires documented use of:

  • Multivitamins
  • The antioxidants vitamin C, vitamin A, vitamin E, carotenoids, and coenzyme Q10.
  • Vitamin D.
  • The B vitamins vitamin B6, vitamin B12, and folic acid.
  • The minerals iron and calcium.
  • Omega-3 fatty acids.
  • Glucosamine, melatonin, and acidophilus.

Recurrence of the breast cancer and death from breast cancer were measured 6 months after chemotherapy ended.

Do Supplements Interfere With Chemotherapy?

Questioning WomanThe study reported:

  • The number of patients using individual antioxidant supplements was too low to determine whether individual antioxidants had any effect on treatment outcomes.
  • When the patients using any antioxidant supplement were pooled into a single group, there was a nonsignificant association between antioxidant supplement use during chemotherapy and an increased risk of breast cancer recurrence and death from breast cancer.
  • Iron use during chemotherapy was significant associated with an increased risk of breast cancer recurrence.
  • Vitamin B12 use during chemotherapy was significantly associated with increased risk of breast cancer recurrence and death from breast cancer.
  • Multivitamin use was not associated with either recurrence or death from breast cancer.
  • The number of patients using the other supplements was too low to determine whether those supplements had any effect on treatment outcomes.

The authors concluded: “Associations between survival outcomes and use of antioxidant and other dietary supplements are consistent with recommendations for caution among patients when considering the use of supplements, other than a multivitamin, during chemotherapy.”

This is the conclusion that generated the headlines you may have seen.

However, in their discussion the authors conceded that a previous review concluded that, “…insufficient evidence existed with regard to the safety of dietary supplements [during chemotherapy] to make recommendations, and that still may be the case.”

I will discuss the reasons for their disclaimer below. However, I will point out that disclaimers like this never seem to make it into the headlines you read.

What Are The Strengths And Weaknesses Of This Study?

strengths and weaknessesThe only strength of this study is that it was performed in the context of an ongoing clinical trial, with surveys conducted before chemotherapy and during chemotherapy to assess supplement use.

However, the study had multiple weaknesses that limit the ability to draw any firm conclusions from the study.

#1: The number of people using supplements in this study was very small. For example:

  • Only 200 people took any antioxidants during chemotherapy.
  • Only 137 people took a vitamin B12 supplement during chemotherapy.
  • Only 109 people took an iron supplement during chemotherapy.

To put this into perspective, if a drug company were submitting a new drug for approval to the FDA, they would be required to submit data from ~50-100-fold more cancer patients to prove that the drug was effective.

With this small number of supplement users, even “statistically significant” observations are questionable.

In contrast, the number of people taking a multivitamin during chemotherapy was 497. Thus, those data were a little stronger than the data for individual supplements.

#2: They did not ask why people were taking supplements. It turns out that the patients who used supplements were older and sicker. They were more likely to be overweight and to have type 2 diabetes.

These are patients who are also more likely to have poor outcomes from chemotherapy. The authors tried to correct for that, but it is virtually impossible to make these corrections when the number of patients taking supplements is so low.

#3: They did not ask about the dose of supplements people were taking.

  • Multivitamins typically contain RDA levels of antioxidants and vitamin B12, so it would be safe to assume that RDA levels of antioxidants and vitamin B12 are safe during chemotherapy.
  • Approximately 50% of the women in the study were premenopausal, so it is likely that they were taking a multivitamin with iron. That suggests that RDA levels of iron are safe during chemotherapy for premenopausal women.

In short, the association between supplement use and poorer outcomes from chemotherapy is tenuous. If there is any association, it is likely with high dose individual supplements rather the lower levels of the same nutrients found in a multivitamin.

Is An Effect Of Supplement Use On Chemotherapy Plausible?

As a biochemist, the next question I ask is whether there is a plausible mechanism for an effect of any of these Look forsupplements on chemotherapy outcomes.

  • For two of the drugs in the regimen (paclitaxel and cyclophosphamide), free radical formation may contribute to their effectiveness, but it is not their main mechanism of action. Thus, it is plausible that high dose antioxidant supplements could make these drugs less effective, but the effect should be relatively small.
  • Tumors require high amounts of iron for proliferation, so it is plausible that excess iron could make tumors more resistant to chemotherapy. However, for premenopausal women, multivitamins with iron did not interfere with the drugs used in this study. Thus, it appears likely that RDA levels of iron, where appropriate, do not interfere with chemotherapy.
  • The authors said that the reason for the observed effects of vitamin B12 on chemotherapy in their study “remains to be understood”. However, the answer might be found in the dosage of vitamin B12. A previous study reported that doses of vitamin B12 that were greater than 20 times the RDA increased the risk of lung cancer.

If people in this study were taking doses of vitamin B12 in excess of 20 times the RDA, it would provide a plausible explanation for B12 interfering with chemotherapy. If not, there is no known explanation. In any case, I do not recommend taking such high doses of any supplement.

Should You Avoid Supplement Use During Chemotherapy?

AvoidNow, let’s get back to the original question: “Should you avoid supplement use during chemotherapy?” If you read the headlines saying, “Supplement Use During Chemotherapy May Be Risky”, you might think that the answer is an unqualified yes. That is also what your doctor is likely to think.

However, when you analyze the study behind the headlines you realize that the evidence supporting the headlines is very weak.

So, that puts us back to where we were before the study was published. Simply put:

  • It is theoretically possible that supplements interfere with chemotherapy, but we don’t know for sure.
  • A pragmatic approach is to avoid supplementation for a day or two before to a day or two after each round of chemotherapy. This is a strategy designed to minimize the possibility that supplementation would interfere with chemotherapy and maximize the possibility that supplementation might aid in recovery between rounds of chemotherapy.

Note: This is generic advice. I am not a medical doctor, so it would be unethical for me to provide individualized advice on how to minimize interactions between supplements and chemotherapy. What I recommend is that you ask your doctor whether my generic recommendations make sense for your cancer and your drug regimen.

If this study advanced our knowledge at all, it would be that:

  • The supplements most likely to interfere with chemotherapy appear to be high dose antioxidants, vitamin B12, and iron supplements.
  • Multivitamins, even multivitamins with iron when appropriate, are unlikely to interfere with chemotherapy.

The Bottom Line 

Recent headlines have warned, “Supplement Use During Chemotherapy May Be Risky”. Is that true?

However, when you analyze the study behind the headlines you realize that the evidence supporting the headlines is very weak.

So, that puts us back to where we were before the study was published. Simply put:

  • It is theoretically possible that supplements interfere with chemotherapy, but we don’t know for sure.
  • A pragmatic approach is to avoid supplementation for a day or two before to a day or two after each round of chemotherapy. This is a strategy designed to minimize the possibility that supplementation would interfere with chemotherapy and maximize the possibility that supplementation might aid in recovery between rounds of chemotherapy.

Note: This is generic advice. I am not a medical doctor, so it would be unethical for me to provide individualized advice on how to minimize interactions between supplements and the chemotherapy drugs you are on. What I recommend is that you ask your doctor whether my generic recommendations make sense for your cancer and your drug regimen.

If this study advanced our knowledge at all, it would be that:

  • The supplements most likely to interfere with chemotherapy appear to be high dose antioxidants, vitamin B12, and iron supplements.
  • Multivitamins, even multivitamins with iron when appropriate, are unlikely to interfere with chemotherapy.

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.

 

Do Antioxidants Reduce Diabetes Risk?

What Diet Is Best For Reducing Your Risk Of Diabetes?

ConfusionI don’t need to tell you that nutrition is confusing. The headlines change day to day. One day antioxidants are good for you. The next day they are worthless. What are you to believe?

That is why I knew you would be skeptical when you saw recent headlines saying things like, “Antioxidants reduce your risk of diabetes” or “An antioxidant-rich diet may prevent diabetes”. You are probably waiting for the other shoe to drop.

You are waiting for the next headline telling you to ignore the previous headlines.

That is why I decided to analyze the study (FM Mancini et al, Diabetologia, 61: 308-316, 2018) behind the headlines and tell you whether the headlines were true or false. More importantly, I wanted to put the study into perspective so you could apply the findings to your life.

How Was The Study Done?

Clinical StudyThe data for this paper came from the Interaction of Genetic and Lifestyle Factors on the Incidence of Type 2 Diabetes (InterAct) study. French women born between 1925 and 1950 were enrolled in the study beginning in 1990.

Women were excluded from the study if they had pre-existing cardiovascular disease, diabetes, or cancer.

In June of 1993 a very extensive dietary questionnaire was mailed to all participants. The antioxidant capacity of each of the foods in the diet was estimated using an existing database, and the total antioxidant content of each woman’s diet was calculated.

A total of 64,223 women (average age = 52) completed the questionnaire and were followed for 15 years. During that time 1751 of the women developed type 2 diabetes.

The study correlated the total antioxidant content of the diet with the risk of developing type 2 diabetes. Coffee was excluded from the analysis because the antioxidants found in coffee are high molecular weight compounds, and it is not clear how well they are absorbed.

The major sources of antioxidants in the French diet were fruits (23%), vegetables (19%), wine (15%), tea (10%), and chocolate (2%). Whole grains and beans are also good sources of antioxidants, but the French (and Americans) don’t eat enough of them to influence their total antioxidant intake.

In case you were wondering why wine and chocolate were among the five top sources of antioxidants, remember this is the French diet we are talking about.

Do Antioxidants Reduce Diabetes Risk?

Diabetes and healthy die The authors of the study divided the women into 5 groups (quintiles) based on the antioxidant content of their diets. Quintile one had the lowest antioxidant intake, and quintile five had the highest antioxidant intake.

Compared to the women in quintile one (lowest antioxidant intake), the risk of developing type 2 diabetes was decreased by:

  • 15% for women in quintile two.
  • 30% for women in quintile three.
  • 38% for women in quintile four.
  • 39% for women in quintile five (highest antioxidant intake).
  • As you might guess from the data above, there was an inverse association between total antioxidant content of the diet and type 2 diabetes up until somewhere between the third and fourth quintiles.
  • Above that antioxidant level, the relationship between dietary antioxidant content and risk of developing type 2 diabetes plateaued.

The authors concluded, “Our findings suggest that the total antioxidant capacity of the diet may play a role in reducing the risk of type 2 diabetes in middle-aged women. As type 2 diabetes represents a high disease burden worldwide, our results may have important public health implications.”

What Diet Is Best For Reducing Your Risk Of Type 2 Diabetes?

While most of the headlines talked about the effect of antioxidant intake on the risk of developing type 2 diabetes, we need to remember that the study was done with antioxidant-rich foods. That raises 3 important questions.

#1: Is it the antioxidants or the foods that decrease the risk of developing type 2 diabetes?

Diabetes-&-Vitamin-CThis was a diet rich in fruits, vegetables, and tea with moderate amounts of wine and chocolate. Although they didn’t make it to the top 5 in this study, whole grains and beans are also a good source of dietary antioxidants. In short, this was a very healthy diet.

That represents a complicating factor. For example, fruits and vegetables are also good sources of non-antioxidant phytonutrients that appear to have health benefits. They are also a good source of fiber and the healthy gut bacteria that eat the fiber.

In short, this study shows that healthy foods reduce the risk of developing type 2 diabetes. Since oxidative stress is thought to play a role in the development of diabetes, it is logical that antioxidants in these foods may help prevent diabetes. However, in reality, we don’t know how much of the risk reduction is due to the antioxidant content of the foods and how much is due to other components of the foods.

#2: Is it healthy foods that decrease the risk of type 2 diabetes, or is it due to decreased intake of unhealthy foods?

food choiceThe skeptic in me wants to ask, “Is the diabetes risk reduction due to the healthy foods included in the diet or does it derive from the fact that those foods displaced unhealthy foods from the diet?” It is also legitimate to ask whether people who eat healthier foods also followed a healthier lifestyle.

Fortunately, the data from this study puts those questions to rest. Compared to women in the lowest quintile of antioxidant intake, women in the highest quintile of antioxidants intake from diet:

  • Drank more sugar-sweetened and artificially sweetened beverages.
  • Ate more processed meat.
  • Ate more calories.
  • Smoked more.
  • Were just as likely to be overweight.

These women were more physically active, but in other ways their diet and lifestyle were no better than women with much less antioxidant intake.

However, we do need to remember that these are French women. Their overall diet and lifestyle is much better than American women. For example, at their worst:

  • 30% were overweight or obese compared to >60% for American women.
  • Intake of processed meat was less than ½ serving/day.
  • Intake of sugar-sweetened beverages was less than 1 ounce/day and intake of artificially sweetened beverages was 1.3 ounces/day.

#3: How much healthy foods do your need to include in your diet to reduce the risk of type 2 diabetes?

fruits and vegetablesThe fact that the beneficial effect of adding antioxidant-rich foods to your diet reduced the risk of developing type 2 diabetes up to a point and then plateaued has important implications. It means you don’t need to be a vegan to reduce your risk of type 2 diabetes. You just need to include enough healthy foods in your diet.

“How much healthy foods”, you might ask. If we look at the point at which the benefit of eating antioxidant-rich foods plateaued in this study, the women were eating:

  • 5-6 servings of fresh fruits and vegetables per day.
  • 4 cups of tea/day.
  • 7 pieces of chocolate/day.
  • 1 glass of wine/day.

If you are an American who is consuming less tea, chocolate, and wine than the French, you will probably want to aim for 6 or more servings of fresh fruits and vegetables per day and include whole grains and beans in your diet.

In a previous issue of “Health Tips From the Professor” I reviewed a study that looked at the optimal intake of fruits and vegetables for various other diseases. That study reported:

  • 10 servings per day is optimal for reducing the risk of heart disease, stroke, and premature death.
  • 6 servings per day is optimal for reducing the risk of cancer.

This study suggests 6 servings of fruits and vegetable per day is likely to also be optimal for reducing the risk of developing type 2 diabetes.

The bad news is that the average American eats one serving of fruit and less than 2 servings of vegetables a day. The good news is that each added serving of fruits and vegetables reduces your risk of disease and premature death. The same is probably true for whole grains and beans, but they weren’t specifically included in these studies.

What About Supplementation?

vitamin COf course, some of you will be tempted to say, “Changing my diet is hard. I’ll just take antioxidant supplements.” Will that work. If we are talking about individual antioxidant supplements, the answer is a clear, “No”. Numerous clinical studies have shown that.

However, one study looked at a holistic approach to supplementation and found that it significantly decreased the risk of developing type 2 diabetes over a 20-year period. That is encouraging, but you need to know that the people in that study were not just consuming antioxidant supplements. They were also consuming:

  • Supplements containing B vitamins, calcium, magnesium, and trace minerals.
  • Plant-based protein supplements that replaced some of the animal protein in their diet.
  • Omega-3 supplements.
  • Probiotic supplements.

So, just as was true for the diet study discussed above, antioxidant supplements may be beneficial in reducing the risk of developing type 2 diabetes. However, it is not possible to separate the benefits of antioxidant supplements from the other supplements included in the study.

The Bottom Line

You may have seen recent headlines claiming, “Antioxidants reduce your risk of diabetes”. The study behind those headlines was actually looking at the effect of antioxidant-rich foods like fruits and vegetables at decreasing the risk of developing type 2 diabetes.

The study did show that increasing the amount of antioxidant-rich foods in your diet decreases your risk of developing type 2 diabetes.

Since oxidative stress is thought to play a role in the development of diabetes, it is logical that antioxidants in those foods may help prevent diabetes. However, in reality we don’t know how much of the risk reduction is due to the antioxidant content of the foods and how much is due to the phytonutrient and fiber content of the foods.

There was an inverse association between total antioxidant content of the diet and type 2 diabetes up until somewhere between the 5 and 6 servings per day of fresh fruits and vegetables. At that point. the beneficial effect of eating antioxidant-rich foods plateaued. Eating 6 servings per day of fresh fruits and vegetables appears to be optimal for reducing the risk of developing type 2 diabetes.

To put that into perspective, a previous study that looked at the optimal intake of fruits and vegetables for various other diseases reported:

  • 10 servings per day is optimal for reducing the risk of heart disease, stroke, and premature death.
  • 6 servings per day is optimal for reducing the risk of cancer.

The bad news is that the average American eats one serving of fruit and less than 2 servings of vegetables a day. The good news is that each added serving of fruits and vegetables reduces your risk of disease and premature death. The same is probably true for whole grains and beans, but they weren’t specifically included in these two studies.

Of course, if you really wish to prevent or reverse type 2 diabetes, a holistic approach including weight control, exercise, diet, and supplementation is best.

For more details, including a more detailed discussion of supplementation, 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.

 

Finally, you should also never think of supplementation as a replacement for a healthy diet. If you wish to reduce your risk of developing type 2 diabetes, I recommend a holistic approach that includes weight control, exercise, diet, and supplementation.

Health Tips From The Professor