A Patient Asks: “Does Your Metabolism Slow Down with Age?”
Common wisdom holds that as we age our metabolism slows down, and that this slowing accounts for the increased propensity we have to gain fat in middle and old age. However, studies argue that this common wisdom has the causal relationship reversed.
As we age, most of us don’t exercise. A lack of exercise then causes a loss of lean body mass (muscle). It’s the loss of muscle that lowers our energy consumption and makes it appear as if our metabolic rates decline as we age. However, there’s nothing about aging itself that lowers our metabolic rate. It’s our lack of activity that lowers our muscle mass, and studies show it’s a lowered muscle mass that lowers the number of calories we burn.
So to prevent a reduction in calorie expenditure as we age, the prescription is exercise. Specifically, weight lifting, which will not only maintain our youthful level of calorie consumption and thereby help stave off increases in fat, but also preserve muscle strength and decrease the risk of frailty as we advance in years.