lifestyle

Do Optimists Live Longer?

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What Does This Study Mean For You? 

Author: Dr. Stephen Chaney 

You have probably heard the statement that optimists live longer before. In fact, you have probably heard so many times you assume it must be true. But is it a myth or is it the truth?

This question is important because it can affect how people feel about themselves. If you are a natural optimist, statements like this support your feeling of self-worth. But if you are naturally pessimistic, statements like this provide one more reason to feel bad about yourself.

For example, a recent article on the topic in WebMD starts with the statement, “Want to live longer? You might want to try improving your outlook on life.” I am mostly optimistic, so I find this statement to be positive and encouraging.

But I am not sure I would feel about this statement if I were pessimistic or depressed and had tried for years to be more optimistic.

Because of this it is important to ask, “How good is the evidence supporting this claim?”

There are several published studies supporting this claim (For example). However,

  • Most of these studies have been performed with white, high-income participants. It is not clear whether these same results would apply to other racial and ethnic groups.
  • There is also the “chicken versus egg” conundrum. The studies claiming that optimists live longer are all association studies. Simply put, that means optimism is associated with longevity, but does not prove cause and effect. That is important because:
    • Some studies show that both a healthy diet and exercise improve mood.
    • Other studies show that optimists tend to take better care of themselves, and that includes both diet and exercise.
    • So, it’s hard to know which comes first – a healthy lifestyle, which creates optimism, or optimism, which creates a healthy lifestyle.
  • Because of this “chicken versus egg” conundrum, it is not clear whether it is a healthy lifestyle or optimism that is the primary cause of greater longevity.

The study (HK Koga et al, Journal of the American Geriatrics Society, 70: 2793-2804, 2022)) I will review today was designed to answer both questions. Specifically, this study was designed to ask:

  • Is higher optimism associated with a longer lifespan and exceptional longevity across diverse racial and ethnic groups?
  • To what extent do lifestyle factors influence this association?

How Was The Study Done?

clinical studyThe data for this study was obtained from the Women’s Health Initiative which enrolled 161,808 postmenopausal women of diverse racial and ethnic groups from 40 medical centers within the United States between 1993 and 1998. The women were aged 50-79 (average = 63.5) at enrollment and were followed for an average of 26 years.

Optimism was assessed at enrollment into the program using the 6-item Life Orientation Test Revised. For each item on the questionnaire, participants were asked to report the degree they agreed with each statement on a scale of 1 = “strongly agree” to 5 = “strongly disagree”. Their responses were summed to create scores ranging from 6 to 30, with 30 being the highest optimism rating.

Lifestyle was assessed on a questionnaire measuring diet quality, physical activity, BMI (a measure of obesity), smoking status, and alcohol consumption. If participants met predefined “healthy standards in each of these categories, they were given a score of 1. Otherwise, their score was 0. Scores from each category were summed to create a composite lifestyle score ranging from 0 (least healthy) to 5 (most healthy).

Longevity was based on survival compared to national averages using the National Death Index (Yes, “Big Brother” is watching you even when you die) to identify and confirm deaths. Deaths of participants were monitored through March 1, 2019. Exceptional longevity was defined as survival to age 90 or older. Overall, 64,301 women (40.3%) died over the 26 years of follow-up.

Finally, women who died within the first 2 years of follow-up were excluded from the data analysis “to mitigate concerns that health status might affect the reporting or experience of optimism levels.” In plain English, people who are within 2 years of dying are often very sick and feel lousy. Even the most optimistic individuals find it hard to maintain an optimistic outlook in those circumstances. This left 159,255 women in the database.

Do Optimists Live Longer?

When comparing women in the highest to women in the lowest quartile of optimism:

  • Longevity was increased by 5.4%, which corresponds to an additional 4.4 years. When this was broken down by race and ethnicity, longevity was increased by:
    • 1% for Non-Hispanic White women.
    • 6% for Black women.
    • 4% for Hispanic women.
    • 5% for Asian women. However, this may have been an underestimate because of the small sample size of this population in the Women’s Health Initiative database.
  • Exceptional longevity (survival ≥ 90 years) was increased 10%.

When the authors used a complex statistical method to assess the contribution of lifestyle to the increase in longevity, they found:

  • Lifestyle contributed to 24% of the increased longevity. When this was broken down by race and ethnicity, lifestyle contributed:
    • 25% for Non-Hispanic White women.
    • 10% for Black women.
    • 24% for Hispanic women.
    • 43% for Asian women.

The authors concluded, “We found that higher levels of optimism were associated with longer lifespan and greater likelihood of achieving exceptional longevity across racial and ethnic groups, suggesting the health benefits of optimism may hold across these groups.”

“The contribution of lifestyle to these associations was evident but modest.”

“As prior work has demonstrated that optimism is modifiable, it may be a novel target for interventions that aim to extend lifespan across diverse racial and ethnic groups.”

What Are The Strengths And Weaknesses Of This Study?

strengths and weaknessesThis is not the first study to suggest that optimists live longer. But it is the best study to date because:

  • It was larger (159,255 participants) than most previous studies.
  • It followed the participants far longer (26 years) than previous studies.
  • It included a more racially and ethnically diverse group of participants than previous studies.
  • It addressed the “elephant in the room” for studies of this type, namely that optimists tend to actively seek a healthier lifestyle, so the “benefits” of optimism could be due to a healthy lifestyle rather than a state of mind. The study employed statistics to estimate that a healthy lifestyle contributed around 25% to the longevity experienced by optimists.

However, the study did have some weaknesses. In my opinion, the most important weaknesses were:

  • Optimism and lifestyle were only assessed at the beginning of the study. No effort was made to determine whether either of these important variables changed during the 26-year study.
  • The relative influence of lifestyle and optimism on longevity was based on a complex statistical analysis. As Mark Twain said, “There are lies, damn lies, and statistics.” Simply put, statistics can sometimes give misleading answers. I would like to see this very important part of the study confirmed using a different method of analysis.

What Does This Study Mean For You?

Questioning WomanAs I shared above, I have some misgivings about this and other studies claiming that optimists live longer. But let’s assume this claim is true. What does that mean for you?

A 5.4% increase in lifespan might not sound like much, but it added 4.4 years to the lives of the women in the study. What would you do with an extra 4.4 years?

And, as the authors of the study pointed out, that’s equivalent to the gain in lifespan for adults engaged in a regular exercise program. Are those benefits addible? We don’t know, but it is possible that an optimist who exercised regularly and had a healthy diet might experience more than a 4-year gain in lifespan.

The authors said, “Although optimism is partly heritable (23-32%), experimental research has demonstrated that optimism is modifiable…”

Let me share a few things that have helped me maintain a more optimistic outlook:

  • Affirmations and visualizations of a positive future.
  • I start my daily prayers by listing the things I am grateful for. For others, a gratitude journal works equally well.
  • Accept positive input. You can accept compliments with humility by simply thanking the person for the compliment. But in your mind, use the compliment to overcome your inner doubts of self-worth.
  • Question negative input. Ask if each critic is the kind of person you want to become. If so, ask if what they said is really true.
  • Create a support network. These are family and friends who will support you when you need it and will give you a gentle kick in the …. when you need that.
  • Trust in a higher power. I know from experience that it is only God who can give me the “peace that passes all understanding” in my most difficult circumstances. And while I am Christian, I think this is a cornerstone of most religions.

Finally, I know that many people are predisposed to depression and pessimism, so I don’t want to be like the author of the WebMD article and tell you, “Want to live longer? You might want to try improving your outlook on life.”

We know that a healthy lifestyle is associated with longevity. And you don’t have to be an optimist to choose a healthy diet, exercise regularly, avoid smoking and excess alcohol intake, and get regular health check-ups.

We also know these things are associated with a longer healthspan which, simply put, is the number of years you live in good health.

So, whether you are a pessimist or an optimist you can live healthier longer.

The Bottom Line

You have probably heard that optimists live longer, but is it true? In the article above I describe the latest study on this topic. It is better than most previous studies on this topic because:

  • It was larger (159,255 participants) than most previous studies.
  • It followed the participants far longer (26 years) than previous studies.
  • It included a more racially and ethnically diverse group of participants than previous studies.
  • It addressed the “elephant in the room” for studies of this type, namely that optimists tend to actively seek a healthier lifestyle, so the “benefits” of optimism could be due to a healthy lifestyle rather than a state of mind. The study employed statistics to estimate that a healthy lifestyle contributed around 25% to the longevity experienced by optimists.

When the study compared women in the highest to women in the lowest quartile of optimism:

  • Longevity was increased by 5.4%, which corresponds to an additional 4.4 years.
  • Exceptional longevity (survival ≥ 90 years) was increased by 10%.
  • Lifestyle contributed to 24% of the increased longevity.

The authors concluded, “We found that higher levels of optimism were associated with longer lifespan and greater likelihood of achieving exceptional longevity across racial and ethnic groups, suggesting the health benefits of optimism may hold across these groups.”

“As prior work has demonstrated that optimism is modifiable, it may be a novel target for interventions that aim to extend lifespan across diverse racial and ethnic groups.”

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.

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My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

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About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Can You Improve Your Healthspan?

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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.

Does Obesity Begin In Kindergarten?

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Is Obesity Caused By Bad Genes Or Bad Lifestyle?

 Author: Dr. Stephen Chaney

 In past issues of “Health Tips From the Professor” I have shared some common sense weight loss tips. But what if it is all for naught? What if there is nothing you can do about your weight?

Fat ChildYou may have seen the headlines suggesting that obesity in kindergarten is a very strong predictor of obesity later in life. If so, you are probably wondering what that means for your kids or grandkids – and what it means for you. You are probably asking questions like:

  • Should you be worrying about that your toddler’s baby fat?
  • What can you do as parents and grandparents to protect the ones you love from a lifetime of obesity and all of the health challenges that involves?
  • Is there anything you can do about overweight and obesity? Are some people just fated to be obese from childhood on?

What Does the Study Actually Show?

This was a very well done study. It followed 7738 children of all socioeconomic classes who were enrolled in kindergarten (mean age 5.6) in the US in 1998 and followed them through the 8th grade (mean age 14.1) (Cunningham et al, New England Journal of Medicine, 370: 403-411, 2014).

When the children entered kindergarten, 12.4% of them were obese, and another 14.9% of them were overweight. By the time they reached the 8th grade 20.8% were obese and 17% were overweight. Those results didn’t make the headlines. They are similar to many previous studies.

The results that made the headlines were:

  • Overweight 5 year olds were 4 times more likely to become obese by age 14 than normal weight 5 year olds.
  • 87% of obese 8th graders (14 year olds) had a body mass index above the 50th percentile in kindergarten, and 75% had a body mass index above the 70th percentile.
  • Only 13% of overweight 8th graders had been normal weight (<50th percentile) in kindergarten, and only 13% of the normal weight 8th graders had been overweight in kindergarten.

These results are fully consistent with earlier studies showing that overweight toddlers are likely to become overweight teens, and overweight teens are likely to become overweight adults. What was unique about this study (and generated the headlines) was the precision of the statistics.

Does Obesity Begin In Kindergarten?

The answer to that question is clearly yes. However, the more important question is what message we, as responsible health advocates, should be sharing with the general public. Let me break that down to some of the most important questions that you are probably asking.

Is Obesity Caused By Bad Genes Or Bad Lifestyle?

Bad GenesTaken on face value, the results of this study might seem to suggest that genetics is the primary cause of obesity. However, if that is the message we convey to the public, it is likely to simply fuel the perception that most overweight individuals are genetically destined to be obese. There is nothing they can do about it. So, why even bother trying?

However, the authors of the study also noted that the percentage of children aged 6 to 11 who are above the 95% percentile of weight has increased 4-fold between 1963 and 2000. Genetics does not change in a mere 37 years (37 generations maybe). That 4-fold increase in severe childhood obesity is clearly driven by lifestyle changes over the past 30 or 40 years.

While nobody knows the exact percentages, a reasonable interpretation of recent research in this area might be:

  • 10-15% of us are genetically destined to be obese. There is little we can do to change our weight, but a healthy lifestyle can significantly reduce our risk of disease.
  • 10-15% of us are genetically predestined to be lean no matter what we eat (Yes. Your suspicions are true). Once again, lifestyle has relatively little influence on our weight, but a healthy lifestyle can significantly reduce our risk of disease.
  • The other 70-80% of us are genetically predisposed to become obese if we adapt the typical American lifestyle. For most of us lifestyle choices can make a big difference in our weight as well as our health.

So the answer to this question is BOTH. For most of us, obesity is caused by bad genes AND bad lifestyle.

When Should We Intervene?

You probably already know that any extra fat cells we develop in childhood never go away. They are always with us, looking for those extra calories they can store as fat.

This study suggests that by the time we are in kindergarten, the die may already be cast. Those extra fat cells may have already developed.

And, for many people, the time to intervene may be even sooner. This study also showed that birth weight plays an important role as well. Children who weighed 9 pounds or more at birth were 2-fold more likely to be obese in kindergarten than children who weighed less than 9 pounds at birth.

Once again, a small percentage of overweight babies is due to genetics, but it is lifestyle choices during pregnancy that lead to the majority of overweight babies.

The authors of the study noted that most public health initiatives (school lunch programs, lifestyle education programs, etc.) are targeted at school aged children. The authors went on to say that by then it may be too late to have any significant effect on the incidence of obesity in our children.

They suggested that we need to place a stronger emphasis on influencing lifestyle changes that affect the weight of babies at birth and are likely to influence whether or not they become obese by the time they reach kindergarten.

That’s not the realm of public health policy. That’s our responsibility.

What Should We Do?

If You Are Pregnant:

  • The old adage “You are eating for two” was never true.
  • Aim for an extra 150 calories during the 1st trimester, 300 during the 2nd and 3rd trimesters (That’s 1 or 2 servings of healthy foods).
  • Aim for little or no weight gain during the 1st trimester and a total of 20-26 pounds during the last two trimesters (a bit less if you are overweight).

If You Have a Young Child Who Is Overweight:

  • Don’t restrict calories. Restricting calories can stunt growth and interfere with normal mental and physical development.
  • Encourage your kids to exercise rather than watching TV and playing video games. You may need to set the example, and that’s a good thing for you as well as for them.
  • Provide your kids with a healthy diet. For most kids, that means more fruits and vegetables and less sugary beverages, fruit juices, and processed snack foods. That may simply mean that you don’t bring those kinds of foods into your house. Again, that would probably be a good thing for everyone in the family.

I know some of you are saying “My kids won’t eat healthy stuff”. Let me give you my take on that.

When I was a kid, my mom had a pretty simple policy. If I didn’t like what she cooked, I didn’t have to eat it. I could simply wait until the next meal – when she would be serving the same kinds of healthy foods again.

I got the message pretty quick. It wasn’t eat healthy or eat junk food. It was eat healthy or go hungry. I decided early on that healthy was better than hungry.

Now, let me step down from my soapbox and summarize.

The Bottom Line:

1)     The latest research suggests that if a child is overweight by kindergarten, they are likely to be overweight for the rest of their lives. So if you want to spare your kids and grandkids  from a lifetime of obesity, you want to intervene early.

2)     A small percentage of those kids are destined to be obese no matter what they do. However, for the vast majority of them obesity can be prevented by a healthy lifestyle.

3)     If you are pregnant, don’t “eat for two”. That is terrible advice. If your pre-pregnancy weight is stable (neither increasing or decreasing), you only need to add a serving or two of healthy foods to your diet during pregnancy. Check with your doctor about the amount of weight gain that is right for you and follow their advice.

4)     If you have a young child who appears to be overweight, don’t restrict their calories. Instead, provide them with healthy food choices and encourage them to exercise.

5)     Finally, if you have been overweight since childhood, don’t despair. For most of us obesity is a combination of genetic predisposition and lifestyle choices. You can’t your genes, but you can change your lifestyle.

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