Tag Archives: longevity

May 26, 2016 · 5:00 PM

You Want Long Telomeres, Don’t You?

Judicious wine consumption is one component of the traditional healthy Mediterranean diet

Judicious wine consumption is one component of the traditional healthy Mediterranean diet

Telomeres are very trendy in the biomedical research community. Like kale and chia seeds with hipster foodies.

Telomeres are repetitive chains of amino acids attached to strands of your DNA. The longer your telomeres, the lower your risk of chronic disease and premature death, generally speaking.

The massive Nurses Health Study showed that women who ate a Mediterranean-style diet had the longer telomeres, which is good. That fits with other evidence of greater longevity and lower chronic disease rates in Mediterranean dieters.

Click for a brief pertinent article at NEJM Journal Watch, which includes a link to the original research report.

To lose weight with the Mediterranean diet, check out my book, Conquer Diabetes and Prediabetes: The Low-Carb Mediterranean Diet.

Steve Parker, M.D.

 

PS: If you didn’t know chia pets have their own Wikipedia page, see my other books.

PPS: We don’t know if telomeres are longer in men eating Mediterranean-style

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September 14, 2015 · 2:00 AM

A Review: “Stop the Clock: The Optimal Anti-Aging Strategy”

dementia, memory loss, Mediterranean diet, low-carb diet, glycemic index, dementia memory loss

“I wish we could have read PD Mangan’s book thirty years ago!”

I read P.D. Mangan’s 2015 book, Stop the Clock: The Optimal Anti-Aging Strategy. I give it five stars in Amazon’s rating system. High recommended.

♦   ♦   ♦

I approached this book with trepidation. I like PD Mangan even though I’ve never met him. We’ve interacted on Twitter and at our blogs. You can tell from his blogging that he’s very intelligent. I don’t know his educational background but wouldn’t be surprised if he has a doctorate degree. My apprehension about the book is that I was concerned it would be brimming with malarkey and scams. Fortunately, that’s not the case at all.

Twin studies have established that 25% of longevity is genetic. That leaves a lot of lifestyle factors for us to manipulate.

I’m not familiar with the anti-aging scientific literature and don’t expect it will ever be something I’ll spend much time on. But it’s an important topic. I’ll listen to what other smart analysts—like Mr. Mangan—have to say about it.

It’s quite difficult to do rigorous testing of anti-aging strategies on free-living humans. So the best studies we have were done with worms, rodents, and monkeys; the findings may or may not apply to us. For example, long-term calorie restriction—about 30% below expected energy needs—is known to prolong life span in certain worms and rodents, with mixed results in rhesus monkeys. It’s the rare person who would follow such a low-calorie diet for years as an experiment. I doubt I would do it even if proven to give me an extra five years of life. I like to eat.

There are several prominent theories of how and why animals age. The author thinks the major factors are:

  1. oxidative stress
  2. inflammation
  3. a decline in autophagy (perhaps most important)

An effective anti-aging program should address these issues.

In the anti-aging chapter of his book, The South Asian Health Solution, internist Ronesh Sinha says that “Lifestyle practices that reduce excess inflammation in the body will help delay the aging process.” Dr. Sinha is a huge exercise advocate and low-carb diet proponent.

Mr. Mangan makes a convincing argument that a good way to forestall aging is to apply hormetic stress. Hormesis is a phenomenon whereby a beneficial effect (e.g., improved health, stress tolerance, growth, or longevity) results from exposure to low doses of an agent or activity that is otherwise toxic or lethal when given at higher doses.

Needs a bit more hormetic stress

Needs a bit more hormetic stress

In case you’re not familiar with hormesis, here’s a major example. Lack of regular exercise leads is linked to premature death from heart disease and cancer. Starting and maintaining an exercise program leads to greater resistance to injury and disease and longer life span. On the other hand, too much exercise is harmful to health and longevity. We see that in professional athletes and excessive marathon runners. Something about exercise—in the right amount—enhances the body’s intrinsic repair mechanisms. That’s the hormetic effect of exercise; one mechanism is by turning on autophagy.

Autophagy is the body’s natural process for breaking down and removing or recycling worn-out cellular structures. This wearing-out occurs daily and at all ages.

If you’re thinking Mr. Mangan recommends exercise as an anti-aging strategy, you’re exactly right. Especially resistance training and high intensity training. His specific recommendations are perfectly in line with what I tell my patients.

Calorie restriction is another form of hormesis; the body reacts by up-regulating stress defense mechanisms. As a substitute for calorie restriction, the author recommends intermittent fasting. Intermittent fasting increases insulin sensitivity, which leads to enhanced autophagy. Fasting seems perfectly reasonable if you think about it, which very few do. Many of us eat every three or four hours while awake, whether a meal or a snack. If you think about it, that’s not a pattern that would be supported by evolution. In the Paleolithic era, we often must have gone 12–16 hours or even several days without food. Hominins without the resiliency to do that would have died off and not passed their genes down to us.

Steve Parker MD, Advanced Mediterranean DIet

Naturally low-carb Caprese salad: mozzarella cheese, tomatoes, basil, extra virgin olive oil

Another anti-aging trick is a low-carb diet, defined as under 130 grams/day, or under 20% of total calories. It may work via insulin signaling and weight control.

Glutathione within our cells is a tripeptide antioxidant critical for clearing harmful reactive oxygen species (free radicals). We need adequate glutathione to prevent or slow aging. Cysteine is the peptide that tends to limit our body’s production of glutathione. We increase our cysteine supply either through autophagy (which recycles protein peptides) or diet. Dietary sources of cysteine are proteins, especially from animal sources. Whey protein supplements and over-the-counter n-acetyl cysteine are other sources. Fasting is another trick that increases cysteine availability via autophagic recyling.

I don’t recall the author ever mentioning it, but if you hope to maximize longevity, don’t smoke. Even if it has hormetic effects. Maybe that goes without saying in 2015.

When I read a book like this, I always run across tidbits of information that I want to remember. Here are some:

  • those of us in the top third of muscular strength have a 40% lower risk of cancer (NB: you increase your strength through resistance training not aerobics)
  • exercise helps prevent cognitive decline and dementia, at least partially via enhanced autophagy
  • exercise increases brain volume (in preparing to do this review I learned that our brains after age 65 lose 7 cubic centimeters of volume yearly)
  • optimal BMI may be 20 or 21, not the 18.5-25 you’ll see elsewhere (higher BMI due to muscle mass rather than fat should not be a problem)
  • Scientist Cynthia Kenyon: “Sugar is the new tobacco.” (in terms of aging)
  • phytochemicals (from plants, by definition) activate AMPK, a cellular energy sensor that improves stress defense mechanisms and increases metabolic efficiency
  • curcumin (from the spice turmeric) activates AMPK
  • coffee promotes autophagy
  • he does not favor HGH supplementation
  • in the author’s style of intermittent fasting, you’re not reducing overall calorie intake, just bunching your calories together over a shorter time frame (e.g., all 2,500 calories over 6-8 hours instead of spread over 24)
  • mouse studies suggest that intermittent fasting could reduce risk of Alzheimer’s disease and Parkinsons disease
  • consider phytochemical supplements: curcumin, resveratrol, green tea extract
  • calorie-restriction mimetics include resveratrol, curcumin, nicotinamide, EGCG, and hydroxycitrate
  • supplemental resveratrol at 150 mg/day improved memory and cognition in humans

The author provides very specific anti-aging recommendations that could be followed by just about anyone. Read the book for details. Scientists are working feverishly to develop more effective anti-aging techniques. I look forward to a second edition of this book in three to five years.

Steve Parker, M.D.

PS: People with certain medical conditions, such as diabetics taking drugs that can cause hypoglycemia, should not do intermittent fasting without the blessing of their personal physician. If you have any question about your ability to fast safely, check with your doctor.

PPS: If you have diabetes or prediabetes and want to reduce your carbohydrate consumption, consider my Low-Carb Mediterranean Diet or Paleobetic Diet.

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April 17, 2015 · 12:25 AM

Live Longer and Reduce Risk of Cancer and Heart Disease With Vegetables and Fruits

MedPageToday has some of the details.  A quote:

The largest benefits were seen in people who ate seven or more servings of fruits and vegetables a day compared with those who ate less than one serving, with the higher level of consumption associated with significantly lower all-cause mortality (hazard ratio 0.67; 95% CI 0.58-0.78), lead researcher Oyinlola Oyebode of University College London, and colleagues, reported online in the Journal of Epidemiology and Community Health.

Spaghetti squash, an under-utilized vegetable

Spaghetti squash, an under-utilized vegetable

The population under study was English. In addition to lower risk of death, the heavy fruit and vegetable consumers had lower rates of cancer and cardiovascular disease. Click for the actual research report.

If seven servings a day seems like a lot, note that a typical serving is only half a cup. You’ll get those with the Low-Carb Mediterranean Diet.

Steve Parker, M.D.

1 cup spaghetti squash with minced black olive, sweet pepper, garlic, salt, pepper, celery

1 cup spaghetti squash with minced black olive, sweet pepper, garlic, salt, pepper, celery

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February 25, 2015 · 12:00 AM

Book Review: The Low Carb Dietitian’s Guide to Health and Beauty

247 pages

247 pages

I just finished reading The Low Carb Dietitian’s Guide to Health and Beauty, written by Franziska Spritzler, RD, CDE, and published in January 2015. CDE, but the way, means Certified Diabetes Educator. Per Amazon’s rating system, I give it five stars (I love it). It’s not written specifically for women with diabetes, but the included recipes are quite consistent with a healthy diabetic diet. Since the author provides the carbohydrate grams with her recipes, you can use them with my Low-Carb Mediterranean Diet and Ketogenic Mediterranean Diet.

*   *   *

This valuable addition to the low-carb literature is unique: No other book covers the beauty and health aspects of low-carb eating specifically in women.

I’m a strong proponent of carbohydrate-restricted eating for weight management and cure or control of certain medical conditions. The great advantages of low-carbing for weight loss are 1) suppression of hunger, and 2) proven greater efficacy compared to other types of dieting. Nevertheless, I wasn’t aware that this way of eating also had potential benefits in terms of beauty maintenance or improvement. The author persuasively makes that case in this ground-breaking book.

Just because she has RD (registered dietitian) behind her name doesn’t mean you just have to take her word for it. Franziska gives us references to the scientific literature if you want to check it out yourself.

The author focuses on health and beauty; the weight loss happens naturally with low-carb eating. That’s a helpful “side effect” since 2/3 of women in the U.S. are overweight or obese.

She covers all the basics of low-carb eating, including the rationale, potential side effects and how to prevent or deal with them, the science of “good fats,” the importance of plant-derived foods and fiber, info on artificial sweeteners, and management of weight-loss stalls.

Then Franziska does something else unique and very helpful. She offers three different eating plans along with a simple test to help determine which is the best for you. The options are 1) low-carbohydrate diet, 2) high-fiber, moderate saturated fat, low-carb diet, and 3) intermittent fasting low-carb diet with weekly treat meal. You can dig right in with a week’s worth of easy meals made from readily available ingredients.

It was interesting for me to learn that the author ate vegan-style and then pescetarian for awhile. In 2011 she was eating the usual doctor-recommended “healthy” low-fat high-fiber diet when life insurance blood work indicated she had prediabetes. So she cut her daily dietary carbs from 150 grams to 50 or less, with subsequent return of the labs to normal ranges.

I only had a few quibbles with the book. For instance, there’s no index, but that’s mitigated by a very detailed table of contents. The font size is on the small side for my 60-year-old eyes. If either of those issues bother you, get the ebook version. “Net carbs” are mentioned briefly before they are defined, which might confuse folks new to low-carbing.

A particular feature that appealed to me is the vegetarian meal options. Low-carb eating is often criticized as being meat-centric. Franziska shows it doesn’t have to be.

I also appreciate that she provides the net carb grams and calorie counts for her meal plans and recipes. All diabetics and many prediabetics need to know the carb grams. Calorie counts come in handy when analyzing the cause of a weight loss stall. Yes, calories still count in weight management.

I don’t think it’s giving too much away to say that the author’s top low-carb beauty foods are avocados, berries, cinnamon, cocoa/dark chocolate, fatty fish, flaxseed, full-fat dairy, green tea, nuts, olives/olive oil, and non-starchy vegetables. I was skeptical at the start of the beauty foods chapter, but Franziska’s scientific references support her recommendations. I’m already eating most of these foods. Now I’m going to try green tea and ground flaxseed (e.g., her flaxseed bread recipe).

The author will also get you going on exercise. I heartily agree with her that exercise is truly a fountain of youth.

Menopausal? The author has your special challenges covered.

If you’re curious about the paleo diet, note that only about a quarter of these recipes are pure paleo. Dairy products disqualify many of them.

Here are a just a few tidbits I picked up, to help me remember them:

  • a blood test called fructosamine reflects blood sugar levels over the previous three weeks
  • you’ll have less wrinkles if you can reduce the advanced glycation end-products (AGEs) in your skin
  • Japanese women on the highest-fat diets have less wrinkling and better skin elasticity
  • soluble fiber from plants helps to reduce appetite, improves blood sugar control, and helps with weight regulation (see her table of high-fiber plants, including soluble and insoluble fiber)
  • seitan is a meat substitute for vegetarians
  • erythritol (an artificial sweetener) may have less gastrointestinal effects (diarrhea, gas, bloating) than many other artificial sweeteners
  • maltitol (another artificial sweetener in the sugar alcohols class) tends to increase blood sugar more than the other sugar alcohols
  • I’m going to try her “sardines mashed with avocados” recipe (Alton Brown popularized sardine-avocado sandwiches, so it’s not as bizarre as it sounds!)

I wouldn’t be surprised if Franziska’s recommendations help men as well as women keep or regain their youthfulness.

Steve Parker, M.D.

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August 3, 2014 · 3:57 AM

Do Low-Carb Diets Cause Premature Death?

Adult life is a battle against gravity. Eventually we all lose.

Adult life is a battle against gravity. Eventually we all lose.

Japanese researchers say low-carb diets are causing premature death. I’m skeptical.

The potentially healthful side effects linked to low-carb eating include reduced weight, higher HDL cholesterol, and lower triglycerides and blood pressure. The Japanese investigators wondered if the improved cardiovascular risk factors seen with low-carb diets actually translate into less heart disease and death.

How Was the Study At Hand Done?

The best way to test long-term health effects of a low-carb diet (or any diet) is to do a randomized controlled trial. You take 20,000 healthy and very similar people—not rodents—and randomize half of them to follow a specific low-carb diet while the other half all eat a standard or control diet. Teach them how to eat, make damn sure they do it, and monitor their health for five, 10, or 20 years. This has never been, and never will be, done in humans. The Nazis may have done it, but it’s not published. In the old days, we could do this study on inmates of insane asylums or prisons.

What we have instead are observational studies in which people voluntarily choose what they’re eating, and we assume they keep eating that way for five or 10+ years. You also assume that folks who choose low-carb diets are very similar to other people at the outset. You depend on regular people to accurately report what and how much they’re eating. You can then estimate how much of their diet is derived from carbohydrate and other macronutrients (protein and fat), then compare health outcomes of those who were in the top 10% of carb eaters with those in the bottom 10%. (We’ve made a lot of assumptions, perhaps too many.)

Of the observational studies the authors reviewed, the majority of the study participants were from the U.S. or Sweden. So any true conclusions may not apply to you if you’re not in those countries. In looking for articles, they found no randomized controlled trials.

The observational studies estimated carb consumption at the outset, but few ever re-checked to see if participants changed their diets. That alone is a problem. I don’t know about you, but I’ve had significant changes in my diet depending on when I was in college and med school, when I was a bachelor versus married, when my income was higher or lower, and when I had young children versus teenagers. But maybe that’s just me.

The researchers looked at all-cause mortality, deaths from cardiovascular disease, and incidence of cardiovascular disease. They don’t bother to define cardiovascular disease. I assume heart attack, strokes, and peripheral vascular disease. (But aren’t aneurysms, deep vein thrombosis, and pulmonary embolism vascular diseases, too?) Wouldn’t you think they’d carefully define their end-points? I would. Since they were going to all this trouble, why not look at cancer deaths, too?

What Did the Investigators Conclude?

Very low-carbohydrate dieters had a 30% higher risk of death from any cause (aka all-cause mortality) compared to very high-carb eaters. The risk of cardiovascular disease incidence or death were not linked with low-carb diets. Nor did they find protection against cardiovascular disease.

Finally, “Given the facts that low-carbohydrate diets are likely unsafe and that calorie restriction has been demonstrated to be effective in weight loss regardless of nutritional composition, it would be prudent not to recommend low-carbohydrate diets for the time being.”

If Low-Carb Dieters Die Prematurely, What Are They Dying From?

The top four causes of death in the U.S. in 2011, in order, are:

  1. heart attacks
  2. cancer
  3. chronic lower respiratory tract disease
  4. stroke

You’ll note that two of those are cardiovascular disease (heart attacks and stroke). So if low-carb diets promote premature death, it’s from cancer, chronic lung disease, or myriad other possibilities. Seventy-five percent of Americans die from one of the top 10 causes. Causes five through 10 are:

  • accidents
  • Alzheimer disease
  • diabetes
  • flu and pneumonia
  • kidney disease
  • suicide

Problem is, no one has ever linked low-carb diets to higher risk of death from any specific disease, whether or not in the top ten. Our researchers don’t mention that. That’s one reason I’m very skeptical about their conclusion. If you’re telling me low-carb diets cause premature death, tell me the cause of death.

Another frustration of mine with this report is that they never specify how many carbohydrates are in this lethal low-carb diet. Is it 20 grams, 100, 150? The typical American eats 250-300 grams of carb a day. If you’re going to sound the alarm against low-carb diets, you need to specify the lowest safe daily carb intake.

For most of my career—like most physicians—I’ve been wary of low-carb diets causing cardiovascular disease. That’s because they can be relatively high in total fat and saturated fat. In 2009, however, I did my own review of the scientific literature and found little evidence of fats causing cardiovascular disease.

If you’re looking for a reason to avoid low-carb diets, you can cite this study and its finding of premature death. I’m not convinced. I’ll turn it around on you and note this study found no evidence that low-carb diets cause cardiovascular disease. The risk of cardiovascular disease had been the traditional reason for physicians to recommend against low-carb diets.

Steve Parker, M.D.

Reference: Noto, Hiroshi et al. Low-Carbohydrate diets and all-cause mortality: A systematic review and meta-analysis of observational studies. PLoS One, 2013; 8(1): e55050

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May 17, 2014 · 3:28 AM

Supplemental Omega-3 Fats’ Effect on Heart Disease, Stroke, Cancer, and Death: No Relationship In a General Population

Salmon is one the the cold-water fatty fish loaded with omega-3 fatty acids

Salmon is one the the cold-water fatty fish loaded with omega-3 fatty acids

I’ve been sitting on this research report a few years, waiting until I had time to dig into it. That time never came. The full report is free online (thanks, British Medical Journal!). I scanned the full paper to learn that nearly all the studies in this meta-analysis used fish oil supplements, not the cold-water fatty fish the I recommend my patients eat twice a week.

Here’s the abstract:

Objective: To review systematically the evidence for an effect of long chain and shorter chain omega 3 fatty acids on total mortality, cardiovascular events, and cancer.

Data sources: Electronic databases searched to February 2002; authors contacted and bibliographies of randomised controlled trials (RCTs) checked to locate studies.

Review methods Review of RCTs of omega 3 intake for 3 6 months in adults (with or without risk factors for cardiovascular disease) with data on a relevant outcome. Cohort studies that estimated omega 3 intake and related this to clinical outcome during at least 6 months were also included. Application of inclusion criteria, data extraction, and quality assessments were performed independently in duplicate.

Results: Of 15 159 titles and abstracts assessed, 48 RCTs (36 913 participants) and 41 cohort studies were analysed. The trial results were inconsistent. The pooled estimate showed no strong evidence of reduced risk of total mortality (relative risk 0.87, 95% confidence interval 0.73 to 1.03) or combined cardiovascular events (0.95, 0.82 to 1.12) in participants taking additional omega 3 fats. The few studies at low risk of bias were more consistent, but they showed no effect of omega 3 on total mortality (0.98, 0.70 to 1.36) or cardiovascular events (1.09, 0.87 to 1.37). When data from the subgroup of studies of long chain omega 3 fats were analysed separately, total mortality (0.86, 0.70 to 1.04; 138 events) and cardiovascular events (0.93, 0.79 to 1.11) were not clearly reduced. Neither RCTs nor cohort studies suggested increased risk of cancer with a higher intake of omega 3 (trials: 1.07, 0.88 to 1.30; cohort studies: 1.02, 0.87 to 1.19), but clinically important harm could not be excluded.

Conclusion: Long chain and shorter chain omega 3 fats do not have a clear effect on total mortality, combined cardiovascular events, or cancer.

Reference: Hooper, Lee et al. Risks and benefits of omega 3 fats for mortality, cardiovascular disease, and cancer: systematic review. BMJ  2006;332:752-760 (1 April), doi:10.1136/bmj.38755.366331.2F (published 24 March 2006).

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Filed under coronary heart disease, Diabetes Complications, Fat in Diet, Fish, Heart Disease, Longevity, Stroke

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April 25, 2014 · 3:09 AM

Live Longer With The Mediterranean Diet Even If You Already Have Cardiovascular Disease

Conquer Diabetes and Prediabetes, Steve Parker MD

Olive oil and vinegar: prominent components of the Mediterranean diet

We’ve known for years that the Mediterranean diet helps prolong life and prevent cancer, heart attacks, type 2 diabetes, dementia, and strokes in folks who start out healthy.

What about patients with existing cardiovascular disease? I’m talking about history of heart attacks, strokes, angina, and coronary artery disease.

Yep. The Mediterranean diet helps them live longer, too.

Details of the study are at the American Journal of Clinical Nutrition. The research was done at Harvard.

Steve Parker, M.D.

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August 24, 2012 · 8:39 AM

“Doc, How Long Will I Live With My Type 1 Diabetes?”

Type 1 diabetics diagnosed in childhood and born between 1965 and 1980 have an average life expectancy of 68.8 years.  That compares to a lifespan average of 53.4 years for those born between 1950 and 1964.  The figures are based on Pittsburgh, PA, residents and published in a recent issue of Diabetes.

Elizabeth Hughes, one of the very first users of insulin injections, lived to be 73.  She started on insulin around 1922.

Average overall life expectancy in the U.S. is 78.2 years—roughly 76 for men and 81 for women.

Don’t be too discouraged if you have diabetes: you have roughly a 50:50 chance of beating the averages, and medical advances will continue to lengthen lifespan.

Steve Parker, M.D.

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March 26, 2012 · 2:00 AM

Is It More Important To Be Fit, Or Healthy Weight?

Men live longer if they maintain or improve their fitness level over time, according to research out of the Cooper Clinic in Dallas, Texas.  Part of that improved longevity stems from reduced risk of death from cardiovascular disease (e.g., heart attack and stroke). 

Compared with men who lose fitness with aging, those who maintained their fitness had a 30% lower risk of death; those who improved their fitness had a 40% lower risk of death.  Fitness was judged by performance on a maximal treadmill exercise stress test.

Body mass index over time didn’t have any effect on all-cause mortality but was linked to higher risk of cardiovascular death.  The researchers, however, figured that losses in fitness were the more likely explanation for higher cardiovascular deaths.  In other words, as men age, it’s more important to maintain or improve fitness than to lose excess body fat or avoid overweight.

Steve Parker, M.D.

Reference: Lee, Duck-chul, et al.  Long-term effects of changes in cardiorespiratory fitness and bodly mass index on all-cause and cardiovascular disease mortality in men.  Circulation, 124 (2011): 2,483-2,490

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October 28, 2011 · 6:21 AM

Does Loss of Excess Weight Improve Longevity?

High WHR

Intentional weight loss didn’t have any effect either way on risk of death, according to recent research out of Baltimore.  Surprising, huh?

Obesity tends to shorten lifespan, mostly due to higher rates of cancer and cardiovascular disease like heart attacks and strokes.  Doctors and dietitians all day long recommend loss of excess weight, figuring it will reduce the risk of obesity-related death and disease.  Many of them are unaware that’s not necessarily the case.  It’s called the “obesity paradox“: some types of overweight and obese patients actually seem to do better (e.g., live longer) if they’re above the so-called healthy body mass index of 18.5 to 24.9.  For instance: those with heart failure, coronary artery disease, and advanced kidney disease.

It’s never really been clear whether the average obese person (body mass index over 30) improves his longevity by losing some excess weight.  That’s what the study at hand is about.

Methodology

Baltimore-based investigators followed the health status of 585 overweight or obese older adults over the course of 12 years.  Half of them were randomized to an intentional weight loss intervention.  All of them had a high blood pressure diagnosis.  Average age was 66.  Average body mass index was 31.  Details of the weight-loss intervention are unclear, but it was probably along the lines of “eat less, exercise more.”

What Did They Find?

The weight-loss group lost and maintained an average of 4.4 kg (9.7 lb) over the 12 years of the study.  This is about 5% of initial body weight, the minimal amount thought to be helpful for improvement in weight-related medical and metabolic problems.  Most of the weight loss was over the first three years.

The men assigned to the weight-loss program had about half the risk of dying over the course of the study, compared to the men not assigned to weight loss.  The authors don’t seem to put much stock in it, however, stating that “…no significant difference overall was found in all-cause mortality between older overweight and obese adults who were randomly assigned to an intentional weight-loss intervention and those who were not.” 

Comments

With regards to the men losing weight, we’re only talking about 100-150 test subjects, a relatively small number.  So I understand why the researchers didn’t make a big deal of the lower mortality: it may not be reproducible.

This same research group did a similar study of 318 arthritis patients and intentional weight loss, finding a 50% lower death rate over eight years.

The authors reviewed many similar studies done by other teams, noting increased death rates from weight loss in some studies, and lesser death rates in others. 

When the studies are all over the place like this, it usually means there’s no strong association either way.  Nearly all the pertinent studies were done on relatively healthy, middle-aged and older folks.  The most reliable thing you can say about the issue is that loss of excess fat weight doesn’t increase your odds of premature death. 

 Remember that patients with coronary heart disease, congestive heart failure, or advanced kidney disease tend to live longer if they’re overweight or at least mildly obese.  It’s the obesity paradox.  Will they live longer or die earlier if they go on a weight-loss program?  We don’t know.

We do know that intentional weight loss helps:

  • prevent type 2 diabetes
  • maintain reasonable blood pressures (avoiding high blood pressure)
  • improves lower limb functional ability

Maybe that’s enough.

Steve Parker, M.D.

Reference: Shea, M.K., et al.  The effect of intentional weight loss on all-cause mortality in older adults: results of a randomized controlled weight-loss trial.  American Journal of Clinical Nutrition, 94 (2011): 839-846.

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