IN THIS UNFAIR game of life, gaining weight is easy, but losing it is far more difficult—particularly as you get older.
“Unfortunately, our metabolism”—the ability of the body to burn calories—“can work against us,” says Mary Wirtz, a clinical dietitian. “This is partly because muscle mass decreases approximately 3 to 8 percent per decade after the age of 30 years old.” And with this muscle-mass loss comes a decrease in basal metabolic rate,
