We are continually bombarded with messages about how fat Americans have become and how bad this weight gain is for our health. Interestingly, while the United States became the fattest nation in the world during the 20th century, our average life span still increased by 27 years. This conundrum makes us realize that nothing is ever quite what is appears or as simple as we would like it to be. In some cases, weight loss can be good (if it is fat weight alone), but it can also be bad if what you’re losing is your muscle mass instead. In fact, sarcopenia, otherwise known as muscle wasting, can vastly decrease a person’s quality of life and speed up the aging process.
Researchers investigated whether sarcopenia is associated with impairment in insulin sensitivity and glucose homeostasis in both obese and non-obese individuals. Their cross-sectional study included over 14,000 subjects, and sarcopenia was assessed using bioelectrical impedance measurements of total muscle mass.
Not surprisingly, they reported that sarcopenia is associated with insulin resistance in all individuals, regardless of body fatness. It was also more likely to be associated with glycemic abnormalities in the obese subjects. Accordingly, they concluded that sarcopenia, independent of obesity, is associated with adverse glucose metabolism, and the association is strongest in individuals under 60 years of age, which suggests that low muscle mass may be an early predictor of diabetes susceptibility.
Why does this matter to those of us working with diabetes patients? The focus of diabetes management is usually on weight loss, along with important lifestyle improvements. Even the Diabetes Prevention Program is used as the shining example of why all patients should attempt to lose at least 5-7% of their body weight. Often times, though, all the patients hear is that they are supposed to lose weight, and more often than not, the exercise portion of their lifestyle “prescription” goes unfilled. However, weight loss without regular physical activity is a recipe for disaster.
One main problem with large amounts of weight loss after you reach middle-age or older is that these losses consist of about 75 percent fat and 25 percent muscle for typical dieters, but when you gain weight back afterward (which is extremely common within six months to a year), a larger percentage (up to 85 percent) of your lost weight is regained as body fat. Having less muscle also lowers your caloric needs, making it easier to gain weight even when you’re eating the same number of calories after your diet as you were consuming beforehand. Furthermore, people who frequently cycle between weight loss and regain eventually will have insufficient muscle left to carry their extra weight, making them become one of the “fat frail” with sarcopenic obesity likely to have a reduced quality of life.
With weight loss, it is essential that you regularly exercise to maintain your muscle mass. In fact, physical activity is likely more important than how many calories you eat when it comes to maintaining a good body weight and your health. Dieters who fail to exercise lose more muscle mass, but exercising during periods of restricted calorie intake stimulates the retention of your muscle, which also keeps metabolism operating at a higher level.
Another consideration is that when losing excess fat, you are also releasing whatever has been stored in your fat tissue along with it, including a lifetime of accumulated toxins like PCBs and DDEs from insecticides. This rapid increase in levels of circulating toxins can actually lead to nerve damage. In nature, bald eagles rapidly die when they lose weight due to the toxins in their brains that get released. This “poisonous infusion” may be the major reason why major weight loss at an older age (when you have had a longer time for toxins to accumulate) is bad for you. Along the same lines, many medications are also stored in fat tissue, and weight loss releases more of them into your bloodstream. Most physicians fail to reduce the dosage of fat-soluble drugs during periods of weight loss, likely making the doses excessively high.
Even if you’re trying to lose some weight, it likely may not be in your best interest once you’re over 60 years of age: even intentional weight loss in older women results in more than twice the risk of hip fractures, frailty, and nursing home admissions. As you can see, there are many good reasons not to attempt to lose significant amounts of weight once you get past a certain age, potential loss of muscle mass being just one of them.
Although maintaining or even gaining muscle mass through training and supplementation cannot completely prevent and reverse declines in your muscle strength over time, keeping what muscle mass you have and trying to gain more should still optimally be your goal in order to stay looking and feeling younger for longer. At present, resistance exercise is the best treatment for restoring lost muscle mass, and doing such training at any age is also an excellent way to prevent muscle losses from occurring in the first place. Really, the focus should always be on gaining or retaining muscle from regular physical activity rather than losing weight, as doing so will eventually lead to healthy fat weight loss without causing a state of sarcopenia.