Eat Smart to Lose Weight
Healthy Weight Maintenance
Inhibits Testosterone Loss
Becoming obese produces a decline in the male sex
hormone equivalent to about
10 years’ worth of aging
By Will Block
Men are but children of a larger growth.
— John Dryden
n poking fun at his own kind, the great English poet was referring to what women have long thought was a certain, uh, immaturity of behavior in the stronger sex. Oh, the stories they could tell . . . but let’s leave that sensitive topic alone, shall we? Instead, let’s dwell on Dryden’s reference to size, a topic that men are also sensitive about. Naturally, men grow larger than women, but the real trouble begins when they grow larger than themselves, in a manner of speaking.
Being overweight is no joking matter if you stop and think about its myriad health consequences—especially if the overweight condition tends toward outright obesity. Looming large on the list of liabilities are increased risks for chronic degenerative diseases, such as cardiovascular disease, neurodegenerative disease, cancer, osteoarthritis, and, of course, type 2 diabetes, which is almost entirely preventable by maintaining a healthy weight.
There are other unfortunate consequences as well, such as social stigma, job discrimination, and a diminished capacity for physical activities (sports, recreational pursuits, playing active games with one’s children or grandchildren, etc.). None of this is to say that an overweight or obese person can’t live a happy, productive, and fulfilling life. Many—perhaps most—can and do. It’s just that their road toward those universal aspirations is steeper and bumpier than for others. It is also, unfortunately, shorter: statistics show that the overweight or obese will die younger than their leaner counterparts.
To Be or Not to Be . . . A Man
The above problems apply equally to men and women. But there is a special consequence of being overweight that applies to men only, and it strikes at the heart of what it means to be a man. Perhaps heart is not exactly the right organ to cite, because we’re talking about testosterone, the giver of all things masculine in a man’s physical and psychological makeup. Almost all of a man’s testosterone comes from his testicles. It’s responsible for his physical features, his virility, his boldness, his competitiveness, his aggressiveness (in the best and worst senses of that term), and almost everything else that distinguishes him, to one degree or another, from the fairer, kinder, gentler sex.
(It’s worth noting that men don’t have a monopoly on testosterone, any more than women have a monopoly on estrogen: just as men have some estrogen in their systems, women have some testosterone in theirs, and it’s largely responsible for their sex drive.)
Low Testosterone Is a Health Risk
It’s a fact of life that both men and women experience an inexorable decline in sex hormones with age. Women’s decline is precipitous, at menopause, whereas men’s is a gradual, ongoing process throughout middle age and beyond. But here are two intriguing questions: (1) Does declining testosterone contribute to poor health? (2) More importantly, perhaps, do poor health and adverse lifestyle factors contribute to the decline in testosterone?
“These results suggest the possibility that
age-related hormone decline may be
decelerated through the management of
health and lifestyle factors.”
The answer to the first question has been known for a long time: it’s yes. The most obvious example of the erosion of good health to which declining testosterone levels contribute is impaired sexual function, but there are others, including type 2 diabetes and loss of muscle mass and bone mass. This should provide a strong incentive to men to try to maintain healthy testosterone levels with advancing age. One way to do that is to stay as healthy as possible, because the answer to the second question is also, apparently, yes.
How to Tell Healthy Men from Unhealthy
Scientists at the New England Research Institutes in Watertown, Massachusetts, sought to establish the relative contributions of aging, health, and lifestyle factors to changes in testosterone levels in community-dwelling (i.e., not institutionalized) older men from the greater Boston area. To this end, they analyzed data on 1667 randomly selected men, aged 40 to 70 at baseline, who were enrolled in the Massachusetts Male Aging Study, a long-term epidemiological study of men’s health and endocrine function. By large margins, the men were: married, employed, white, and high school graduates.
The men’s testosterone levels and a variety of other factors, including weight, were measured at the beginning and the end of the study period, which lasted about 15 years, on average, and once in between, after about 9 years. Their medical histories were taken, of course, along with information on their health-related lifestyle choices (e.g., exercise, smoking, and drinking); dietary information was obtained through standardized questionnaires. They were also evaluated for symptoms of depression, and a comprehensive inventory of their medications was taken.
Men who were taking testosterone preparations were excluded from the study, for obvious reasons, as were men who had prostate cancer, because a common treatment for that disease is a type of hormone therapy that strongly suppresses testosterone levels.*
A man was considered: obese if his body mass index (BMI) was 30 or greater; sedentary if his daily energy expenditure through physical activity did not exceed 200 calories; a heavy drinker if he consumed more than six drinks daily; and depressed if he scored greater than a certain number on a standardized test of depressive symptoms. Men who had no chronic illness, did not smoke, did not drink heavily, were not obese, and used fewer than six medications were considered to be healthy.
Obesity Is a Risk Factor for Testosterone Loss
Over the 15-year period, many of the men were lost to follow-up—only 584 remained for whom the requisite data could be collected. After controlling for the different ages at baseline of the men in that group, the researchers found a 14.5% decline in total testosterone per decade of aging and a 27.0% per decade decline in free testosterone. Free testosterone is the most important component of total testosterone; the rest is not free—it’s chemically bound to proteins in the blood and has varying degrees of bioavailability. With age, free testosterone declines not only absolutely but also relatively, as a percentage of total testosterone—a double whammy.
When these trends were evaluated only in the men who were deemed healthy throughout the study period, the declines in total testosterone and free testosterone were significantly less severe: 10.5% per decade and 22.8% per decade, respectively. This suggested that a substantial proportion of testosterone loss was due to health- and lifestyle-related factors. Obesity, in particular, was identified as a major culprit. Analysis of the data indicated that a 4-to-5-point increase in BMI, if it crossed the obesity threshold value of 30, was associated with a loss of total testosterone comparable to that of about 10 years of aging; the loss of free testosterone was much less, however, corresponding to about 3 years of aging.
Other Health and Lifestyle Factors Also Pose Risks
Another major loss of testosterone (about 10 years’ worth for both total testosterone and free testosterone) was brought about by the death of one’s wife. Less severe, but still substantial, was the loss of testosterone (about 5 to 6 years’ worth for both forms) caused by type 2 diabetes. (See the sidebar for more on this.) Additional loss factors were hypertension and taking large numbers of medications. Smoking, on the other hand, raised testosterone levels significantly. If you are a smoker (although it’s hard to imagine that any reader of Life Enhancement would be), do not take this as an excuse to continue the habit. Smoking may help keep your testosterone levels up, but it will also kill you. It’s really not worth it.
Does Low Testosterone Lead to Diabetes?
Obesity, the primary risk factor for type 2 diabetes, is associated with significant declines in testosterone levels, as we’ve seen in the accompanying article. And diabetes, independently of obesity, is also associated with declining testosterone levels. But is the converse true—are low testosterone levels a causal factor in diabetes, independently of obesity?
The answer appears to be yes, based on data from a large epidemiological study, NHANES III (Third National Health and Nutrition Examination Survey), in which researchers evaluated the relationship between testosterone levels and diabetes in 1413 American men aged 20 or older. Dividing this group of men, 101 of whom had diabetes, into tertiles (thirds) based on their free testosterone levels, the researchers found that those in the lowest tertile were four times as likely to have diabetes as those in the highest tertile, whether they were obese or not. The correlation held even when all men with abnormally low testosterone levels were excluded from the data analysis, indicating that the effect was not caused primarily by those men. (Interestingly, no correlation with diabetes was seen for total testosterone levels.)
The authors concluded that men whose free testosterone levels are low but still within the normal range are at increased risk for diabetes, whether they’re obese or not, because testosterone and the other male sex hormones appear to influence glucose metabolism and the onset of insulin resistance, the precursor to diabetes.
- Selvin E, Feinleib M, Zhang L, Rohrmann S, Rifai N, Nelson WG, Dobs A, Basaria S, Golden SH, Platz EA. Androgens and diabetes in men. Results from the Third National Health and Nutrition Examination Survey (NHANES III). Diabetes Care 2007;30:234-8.
In evaluating the relative contributions of aging, health, and lifestyle factors in testosterone loss, the authors concluded,
. . . although aging effects predominate overall, health and lifestyle outstrip aging effects in a substantial number of subjects. . . . The results presented here suggest that although hormone declines appear to be an integral part of the aging process, rapid declines need not be dismissed as inevitable. . . . These results suggest the possibility that age-related hormone decline may be decelerated through the management of health and lifestyle factors.
How to Lose Weight
All the advice in all the books on weight loss can be distilled into one simple precept: to lose weight, you must burn more calories than you consume, or consume fewer calories than you burn. Period. There are many ways to accomplish this objective, but they all boil down to the twin pillars of good health: diet and exercise. Without significant intervention in one arena or the other (or both), weight loss is impossible.
Exercise is a no-brainer: any kind of physical activity burns calories, so you simply can’t go wrong there. Diet, by contrast, is complicated, because the options are limitless, and the consequences can go either way. Although “diet” usually means eating less, it can also mean eating smart, resulting in one or more of three important consequences: (1) an intake of fewer calories, (2) a reduced absorption of the calories taken in, and (3) a more efficient burning off of the calories absorbed, through internal biochemical processes. If you’re really smart, you can accomplish all this while satisfying your hunger with good foods (and beverages) that you enjoy.
How to Eat Smart
One key to smart eating is to exert glycemic control by lowering the average glycemic index of your meals. You can do this by selecting low-glycemic-index foods and augmenting them with naturally beta-glucan-rich barley, as well as by using resistant starch instead of regular starch, and erythritol instead of sugar. Another way to shift your shape is to drink certain polyphenol-rich teas that inhibit fat synthesis and promote thermogenesis. Finally, you can enhance glucose metabolism and weight loss via a number of dietary supplements, such as 3-acetyl-7-oxo-DHEA, chromium polynicotinate, resveratrol, grape seed extract, and purple corn color.
A fine way to lose weight, of course, is the time-honored method of forgoing a meal now and then in favor of having sex—which is all the more likely to occur if you keep those testosterone levels up where they belong. Remember the old saying, “Reach for your mate instead of your plate.”
- Travison TG. Araujo AB, Kupelian V, O’Donnell AB, McKinlay JB. The
relative contributions of aging, health, and lifestyle factors to serum testosterone decline in men. J Clin Endocrinol Metab 2007;92:549-55.
Will Block is the publisher and editorial director of Life Enhancement magazine.