Aging, Weight Gain, and Weight Loss

Overweight, obesity, and physical inactivity are smoking’s close cousins in preventable causes of mortality, leading to over 300,000 deaths annually.  The societal costs of these conditions* may be as high as $400 billion per year.  Therefore, upon reading the May 6 blog post from Sissela Bok and the May 20 post from Steven Schroeder, it seemed appropriate to address two questions that came to mind from their posts:  1) Do people over the age of 65 continue to fall prey to overeating, physical inactivity and weight gain?, and 2) Is 65 too late to tackle overweight, obesity, and physical inactivity? 

To answer question 1, we observe prevalence estimates and weight trajectories over time.  Among Americans 60+ years of age, nearly 74% of women and 77% of men are either overweight (body mass index of  25 or higher) or obese (BMI  of 30 or higher).  The rates are even higher for certain racial/ethnic groups in this age group; nearly 90% of African-American women or Hispanic men are overweight or obese.  These numbers are staggering and rival or surpass the prevalence for any other age group.

 But what about weight gain over time?  When does it stop?  Data from long-standing cohorts demonstrates that both men and women continue to gain weight, on average, through middle-age with some flattening of the trajectory compared to younger age groups.  By the time men and women reach age 65, some weight loss thereafter is evident.  However, slower weight gain and eventually some weight loss with aging probably reflect gradual loss of muscle mass over time, coexisting with rising body fat mass.

 Consistent with this data are findings of increasing calorie consumption over the last several decades among those over the age of 60.  Older people are drinking more soda, consuming more fast food, and snacking on high-calorie foods, just like everyone else.  And, these behaviors are cumulative.  Increases in weight and/or fat mass during older ages are on top of any prior gains, which were substantial in the over 65 group because they lived much of their adulthood during the heart of the obesity epidemic.  Living for longer periods at unhealthy body weights only exacerbates the development o f chronic disease and functional limitations that are associated with overweight and obesity.  Coupled with weight gain, physical inactivity is typical and, if anything, has increased over time in all age groups. 

But, on to question 2.  Is older age too late to address body weight and physical inactivity?  Are the harms already embodied and unlikely to be reversed?  Prior observational research has been mixed, showing that weight loss after age 65 may be associated with higher morbidity and mortality. However, a 2011 study by Villareal, et al., in the New England Journal of Medicine provided critical evidence in support of the concept that it’s never too late.  This study enrolled 107 patients who were 65+ years old, sedentary, mild-to-moderately frail, and obese  in a randomized controlled trial comparing four treatment arms: 1) a weight management program that included weekly group meetings with dieticians seeking to achieve a daily calorie deficit of 500 to 750 calories, 2) a three times weekly, 90-minute, group exercise program, supervised by a physical therapist, that included aerobic exercises, resistance training, and flexibility and balance exercises; 3) a combination of the weight management and exercise programs, and 4) a control group that received monthly advice about a healthy lifestyle from research staff.

The results were impressive.  All of the intervention groups had substantial improvements in physical functioning and exercise tolerance compared to the control group, with the greatest improvements for those in the combined exercise and diet group.  Strength was improved only in the groups that participate in the exercise program, and weight loss was achieved (18 to 21 pounds) only in the groups enrolled in the weight management program.  In other words, losing weight and improving physical activity can have incredibly important and positive influences on health after age 65.  We need more studies like this, in older age groups, to make certain that these effects are consistent.

So, I think our answers to questions 1 and 2 are a resounding “yes” and “no”.  Older people are vulnerable to weight gain, physical inactivity, and overeating, and it’s never too late to address these issues.  Weight loss and starting exercise are achievable and clearly improve functional status.  Treatments for obesity in this age group include all of the same treatments for younger people, including lifestyle changes for everyone and medications and bariatric surgery for selected patients.

Medicare has begun recognizing the potential benefits of lifestyle changes and now covers intensive behavioral therapy for obese patients.  However, the documentation and billing process for this treatment is overly burdensome, leading to limited use among providers.  Medicare does not cover weight loss medications but does cover weight loss surgery.  The selection process for medications and bariatric surgery among older patients is particularly important because of a highest risk of morbidity and mortality undergoing bariatric surgery and much uncertainty about the safety of using medications (really for any age group but particularly geriatric groups).  The medication labels for the primary medications FDA-approved for the treatment of obesity (orlistat, phentermine, lorcaserin, phentermine/topiramate) each recommend caution when using in geriatric populations because of inadequate samples of geriatric patients in trials.

*The AMA recently classified obesity as a disease.  The effects of this classification are not yet clear but could open the doors to more widespread coverage of obesity treatment programs.

Jason Block, 37, is a general internal medicine physician, and Assistant Professor in the Department of Population Medicine at Harvard Medical School, where he is Associate Director of the Obesity Prevention Program. His research examines geographic influences on the obesity epidemic and interventions to promote weight loss and overall wellness, especially at the environmental level.