Walking Your Way To Health

How Much Should You Walk? 

Author: Dr. Stephen Chaney 

Overweight People ExercisingThe new year is almost here. If you are like millions of Americans, you may already be making plans to join a gym, get a personal trainer, or join a spin class.

The problem is these are all expensive options. And a good portion of that money is wasted. To put it into perspective, let’s look at some statistics

  • Around 6 million Americans buy gym memberships every January.
  • 67% of those memberships are never used.
  • For those memberships used in January, another 50% are not in use 6 months later.
  • Americans spend about 1.6 billion dollars on unused gym memberships every year.
  • And that doesn’t include those gym memberships that are only occasionally used.

If you want to get fit and healthy in the new year, perhaps you should consider a less expensive option – like walking. Your only investments are a good pair of walking shoes and a device that keeps track of the number of steps you take (eg, Fitbit, smart watch, or smart phone).

You still may give up on your New Year’s goal of getting fitter at some point. But you won’t have wasted so much money.

Of course, you probably have some questions about the benefits of walking, such as:

  1. Is walking enough to significantly improve my fitness and health?

2) How far (how many steps) should I walk?

3) How fast should I walk?

Fortunately, two recent studies (B del Pozo-Cruz et al, JAMA Internal Medicine, 182: 1139-1148, 2022; J del Pozo-Cruz et al, Diabetes Care, 45: 2156-2158, 2022) have answered all three questions.

How Were These Studies Done?

clinical studyThe first study (B del Pozo-Cruz et al, JAMA Internal Medicine, 182: 1139-1148, 2022) followed 78,500 participants (average age 61, 55% female, 97% white) enrolled in the UK Biobank study for an average of 7 years.

At the time of enrollment, each participant was given an accelerometer (a device that measures the number and frequency of steps) to wear on their dominant wrist for 24 hours/day for 7 days. The investigators used the accelerometer data to categorize several types of physical activity.

  • Daily step counts (the average number of steps per day for 7 days). These step counts were further subdivided into two categories:
  • Incidental steps (It was assumed that ˂40 steps/min represented steps taken that were incidental to normal daily activities).
  • Purposeful steps (It was assumed that ≥40 steps/min represented steps taken as part of planned exercise).
  • Stepping intensity (the highest frequency of steps/min averaged over 30 min intervals for all 7 days).

At the end of the study, each of these variables was correlated with the risk of premature deaths due to all causes, cancer, and heart disease.

The second study (J del Pozo-Cruz et al, Diabetes Care, 45: 2156-2158, 2022) was similar except that it:

  • Used data from 1687 adults (average age = 55, 56% male, with diabetes or prediabetes when the study began) in the 2005-2006 National Health and Nutrition Examination Survey in the US.
  • Followed participants for 9 years instead of 7.
  • Only measured total steps/day
  • Correlated total steps/day with premature death for participants who already had prediabetes or diabetes when they entered the study.

Walking Your Way To Health

Study 1 looked at the effect of walking on health outcomes in multiple ways.

woman walking dog#1: Increase in number of steps/day:

  • On average study participants took an average of 7200 steps per day, but this ranged from a low of 3,200 steps/day to a high of 12,200 steps/day.
  • Each increase of 2,000 steps/day was associated with a:
    • 8% decrease in all-cause mortality.
    • 11% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.
  • Overall, increasing from 3,200 steps/day to 10,000 steps/day decreased all-cause, cancer, and heart disease mortality by around 36%.
  • There was no minimum threshold to this beneficial effect of walking on the risk of premature death.
  • The benefits of walking appeared to plateau at 10,000 steps/day.

#2: Increase in number of incidental steps/day (steps taken that are incidental to normal daily activities):

  • On average study participants took 3240 incidental steps/day, but this ranged from a low of 2,100 steps/day to a high of 4,400 steps/day.
  • Each 10% increase in incremental steps/day was associated with a:
    • 6% decrease in all-cause mortality.
    • 6% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.

#3: Increase in number of purposeful steps/day (steps taken as part of planned exercise):

  • On average study participants took 4,600 purposeful steps/day, but this ranged from a low of 1,600 steps/day to a high of 8,600 steps/day.
  • Each 10% increase in purposeful steps/day was associated with a:
    • 7% decrease in all-cause mortality.
    • 8% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.

#4: Increase in speed of walking or cadence. The measurement they used was “peak-30 cadence” – the Walking Fasthighest average steps/min during a 30-minute interval within a day:

  • On average study participants had a “peak-30 cadence” of 76 steps/min, but this ranged from a low of 47 steps/min to a high of 109 steps/min.
  • Each 10% increase in “peak-30 cadence” was associated with a:
    • 8% decrease in all-cause mortality.
    • 9% decrease in cancer mortality.
    • 14% decrease in heart disease mortality.
  • The benefits of walking rapidly (increase in “peak-30 cadence”) were in addition to the benefits seen by increasing the number of steps per day.
  • Overall, increasing from a “peak-30 cadence” of 47 steps/min to 109 steps/min decreased all-cause, cancer, and heart disease mortality by an additional 34%.
  • There was no minimum threshold to this beneficial effect of increasing “peak-30 cadence” (the speed of walking) on the risk of premature death.
  • The benefits of increasing “peak-30 cadence” appeared to plateau at 100 steps/min.

#5 Effect of walking on the prevention of heart disease and cancer: The investigators measured this by strong heartlooking at the effect of walking on the “incidence” of heart disease and cancer (defined as new diagnoses of heart disease and cancer) during the study. They found.

  • Each 2,000-step increase in the total number of steps/day decreased the risk of developing heart disease and cancer by 4% during this 7-year study.
  • Each 10% increase in the number of purposeful steps/day decreased the risk of developing heart disease and cancer by 4% during this study.
  • Each 10% increase in “peak-30 cadence” decreased the risk of developing heart disease and cancer by 7% during this study.

The authors concluded, “The findings of this population-based…study of 78,500 individuals suggest that up to 10,000 steps/day may be associated with a lower risk of mortality and cancer and CVD incidence. Steps performed at a higher cadence may be associated with additional risk reduction, particularly for incident disease.”

Study 2 extended these findings to diabetes. They started with participants that had either prediabetes or diabetesdiabetes and followed them for 9 years. They found that:

  • Study participants with prediabetes ranged from a low of 3,800 steps/day to a high of 10,700 steps/day.
    • Prediabetic participants walking 10,700 steps/day were 25% less likely to die during the study than participants walking only 3,800 steps/day.
  • Study participants with diabetes ranged from a low of 2,500 steps/day to a high of 10,200 steps/day.
    • Diabetic participants walking 10,200 steps/day were also 25% less likely to die during the study than participants walking only 2,500 steps/day.
  • Even small increases in the number of steps per day decreased the risk of premature death for both prediabetic and diabetic participants.
  • Once again, 10,000 steps/day appeared to be the optimal dose to lower the risk of premature death for both diabetic and prediabetic patients.

The authors of this study concluded, “Accumulating more steps/day up to ~10,000 steps/day may lower the risk of all-cause mortality of adults with prediabetes and diabetes.”

How Much Should You Walk?

Walking CoupleThat was a lot of information. You are probably wondering what it means for you. Let’s start with the big picture:

  • Going from couch potato to 10,000 steps per day may reduce your risk of premature death due to all causes, cancer, and heart disease by 36% (24% if you are already prediabetic or diabetic).
  • Increasing the speed with which you walk from 47 steps/min to 109 steps/min sustained for 30 minutes may reduce your risk of premature death by an additional 34%.

In other words, simply walking more and walking faster can have a significant on your health. I am not recommending walking as your only form of exercise. I’m just saying not to consider it inferior to other forms of exercise.

  • There is no lower limit to the benefits of walking. Even small increases in the number of steps/day you take and the speed with which you walk may have a beneficial effect on your health.

In other words, you don’t need to speed walk 10,000 steps/day to reap a benefit from walking. Even small increases are beneficial. That’s good news for those of you who may not be able to speed walk long distances. It also means that if you are a couch potato, you don’t need to attempt 10,000 steps at high speed from day 1. You can work up to it gradually.

  • Incidental walking (walking that is incidental to your daily activities) is almost as beneficial as purposeful walking (walking as part of a planned exercise).

That’s good news for those of you who may not have time for long walks. It also means that advice like “park your car at the far end of the parking lot and walk” or “take the stairs rather than the elevator” can have a meaningful impact on your health.

  • The benefits of walking appear to max out at around 10,000 steps per day and a cadence of 100 steps/min sustained for 30 minutes.

That means once you get to those levels, it’s time to consider adding other kinds of exercise to your regimen. More and faster walking may offer little additional benefit.

Finally, in the words of the authors, “This information could be used to motivate the least active individuals to increase their steps and the more-active individuals to reach the 10,000-step target.”

The Bottom Line 

The new year is almost here. If you are like millions of Americans, you may already be making plans to join a gym, get a personal trainer, or join a spin class.

If you want to get fit and healthy in the new year, perhaps you should also consider a less expensive option – like walking.

Of course, you probably have some questions about the benefits of walking, such as:

1) Is walking enough to significantly improve my fitness and health?

2) How far (how many steps) should I walk?

3) How fast should I walk?

Fortunately, two recent studies have answered all three questions. They found:

  • Going from couch potato to 10,000 steps per day may reduce your risk of premature death due to all causes, cancer, and heart disease by 36% (24% if you are already prediabetic or diabetic).
  • Increasing the speed with which you walk from 47 steps/min to 109 steps/min sustained for 30 minutes may reduce your risk of premature death by an additional 34%.
  • There is no lower limit to the benefits of walking. Even small increases in the number of steps/day you take and the speed with which you walk may have a beneficial effect on your health.
  • Incidental walking (walking that is incidental to your daily activities) is almost as beneficial as purposeful walking (walking as part of a planned exercise).
  • The benefits of walking appear to max out at around 10,000 steps per day and a cadence of 100 steps/min sustained for 30 minutes.

In the words of the authors of these studies, “This information could be used to motivate the least active individuals to increase their steps and the more-active individuals to reach the 10,000-step target.”

For more details on 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.

 

Does An Apple A Day Keep Diabetes Away?

A Holistic Approach To Preventing Diabetes 

Author: Dr. Stephen Chaney

VillainLow carb enthusiasts will tell you that carbohydrates are the villain. They tell you that cutting carbohydrates out of your diet will reduce your risk of obesity, diabetes, heart disease, and cancer.

If they limited their list of villainous foods to foods with white flour and/or added sugars, many nutrition experts would agree with them. There is widespread agreement in the nutrition community that we eat far too much of these foods.

However, I don’t have to tell you that many low carb diets also eliminate fruits, whole grains, and beans from their diets based solely on the carbohydrate content of these foods. Is this good advice? Is there any data to back up this claim?

The short answer is no. In fact, most studies suggest the opposite is true. I have covered these studies in previous issues of “Health Tips From The Professor”. For example:

  • In one issue I covered studies showing the people consuming primarily plant-based diets weigh less, have less inflammation, and have a lower risk of diabetes, heart disease, and high blood pressure than people consuming the typical American diet.
  • In another issue I shared studies showing that women consuming a plant-based low carb diet weigh less, and have reduced risk of diabetes and heart disease than women consuming a meat-based low carb diet.

However, these studies looked at the effect of the whole diet, not individual components of the diet.

This week I will review a study (NP Bondonno et al, The Journal of Clinical Endocrinology & Metabolism, 2021, doi:10.1210/clinem/dgab335) looking at the effect of fruit consumption on the risk of developing type 2 diabetes.

Next week I will review a study looking at the effect of whole grain consumption on the risk of developing type 2 diabetes.

How Was This Study Done?

Clinical StudyThis study made use of data from the Australian Diabetes Obesity And Lifestyle Study. This study recruited 7675 Australians 25 years or older from 7 states and territories in Australia in 1999 and 2000 and followed them for 5 years. The characteristics of the study population were:

  • Gender = 45% male, 55% female
  • Average age = 54 years
  • Average BMI = 26.8 (slightly overweight)
  • Did not have diabetes at time of entry into the study.

The participants filled out a food frequency questionnaire at the time of entry into the study. This questionnaire was used to analyze:

  • the amount of fruit consumed.
  • the amounts of vegetables, red meat, and processed meat consumed.
  • how many calories were consumed.

At the time of entry into the study several measurements were taken that assessed whether the participants had an increased risk of developing diabetes (otherwise known as pre-diabetes). These included:

  • Fasting plasma glucose and insulin levels.
  • A 2-hour glucose tolerance test. The results of this test were used to calculate insulin resistance and insulin sensitivity.

The study also recorded any participants who were diagnose with diabetes over the next 5 years.

Does An Apple A Day Keep Diabetes Away?

AppleThe data from this study were statistically adjusted for confounding variables (Other variables that might affect the risk of diabetes). Many confounding variables were included in the adjustment, but the ones of interest to us are age, sex, physical activity, obesity, caloric intake, and intakes of alcohol, vegetables, red meat, and processed meat.

After adjustment for all these variables the results were:

At the beginning of the study:

  • Fruit intake was inversely associated with insulin levels and insulin resistance.
  • Fruit intake was directly associated with insulin sensitivity.

In other words, the more fruit people ate, the less likely they were to have prediabetes at the time they entered the study.

At 5 years:

  • Fruit intake was inversely associated with diabetes.
  • Fruit juice had no effect on diabetes risk.

In other words, the more fruit people ate, the less likely they were to develop diabetes 5 years later. Fruit juice, on the other hand, had no beneficial effect on diabetes risk.

  • The benefit of fruit intake plateaued at 2-3 servings a day.

In other words, you don’t need to become a fruitarian. A modest intake of fruit (2-3 servings a day) is all you need.

In case you haven’t noticed, 2-3 servings of fruit a day matches USDA recommendations – and the recommendations of almost every other governmental and medical organization. What do they know that you didn’t know?

The most commonly eaten fruits in this study were apples (23%), bananas (20%), and oranges and other citrus fruits (18%). Enough people ate these three fruits that their effects on the risk of developing diabetes could be analyzed separately.

  • The beneficial effect of each of these fruits plateaued at about one serving a day.

In other words, an apple a day does keep diabetes away. However, apples can’t do it alone. You need a variety of fruits for optimal benefit.

The authors concluded, “A healthy diet including whole fruits, but not fruit juice, may play a role in mitigating type 2 diabetes risk.”

A Holistic Approach To Preventing Diabetes

Myth Versus FactsThis study explodes the myth that you should avoid fruits if you want to prevent diabetes. Yes, fruits do contain sugar, but:

  • They also contain fiber, which slows the absorption of that sugar.
  • The sugar is trapped in a cellular matrix, which must be digested before that sugar can be released. That also slows the absorption of sugar.

This is why fruit consumption reduces the risk of diabetes while fruit juice consumption does not.

However, I don’t want to give you the impression that you can reduce your risk of diabetes just by consuming more fruit. You need a holistic approach. Here are diabetes prevention tips from the American Diabetes Association.

  1. Get more physical activity.
    • The greatest benefit comes from a fitness program that includes both aerobic exercise and resistance training.

2) Get plenty of fiber.

    • Include fruits, vegetables, whole grains, beans, and nuts in your diet.

3) Lose extra weight.

    • One recent study showed that losing as little as 7% of your body weight and exercising regularly could reduce your risk of developing diabetes by almost 60%.

4) Skip fad diets and simply make healthier food choices.

    • “Low-carb diets, the glycemic index diet, and other fad diets may help you lose weight initially. But their effectiveness at preventing diabetes and their long-term effects aren’t known. And by excluding or strictly limiting a particular food group, you may be giving up essential nutrients.”

5) See your doctor on a regular basis and have your blood sugar tested, especially if you are overweight, have a family history of diabetes, or are over 45.

The Bottom Line

Low carb enthusiasts tell you to eliminate fruits from your diet if you want to reduce your risk of developing diabetes. Is this true? Is it good advice?

A recent study put this advice to the test. The study recruited 7675 Australians 25 years or older and followed them for 5 years. It correlated fruit intake with measures of prediabetes at the beginning of the study and correlated fruit intake with the onset of diabetes over the next 5 years. Here is what the study found.

  • The more fruit people ate, the less likely they were to have prediabetes at the time they entered the study.
  • The more fruit people ate, the less likely they were to develop diabetes 5 years later.
  • The benefit of fruit intake plateaued at 2-3 servings a day. In other words, you don’t need to become a fruitarian. A modest intake of fruit (2-3 servings a day) is all you need.

The most commonly eaten fruits in this study were apples (23%), bananas (20%), and oranges and other citrus fruits (18%). Enough people ate these three fruits that their effects on the risk of developing diabetes could be analyzed separately.

  • The beneficial effect of each of these fruits plateaued at about one serving a day.

In other words, an apple a day keeps diabetes away. However, apples can’t do it alone. You need a variety of fruits for optimal benefit.

The authors concluded, “A healthy diet including whole fruits, but not fruit juice, may play a role in mitigating type 2 diabetes risk.”

For more details about this study and a holistic approach to reducing your risk of diabetes recommended by the American Diabetes Association, 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.

Health Tips From The Professor