NYT article on metabolism

The findings using this large pool of data suggest that many of our commonly held beliefs about metabolism are wrong.

First, after controlling for body size and muscle mass, the researchers found there are no metabolic differences between men and women. (Yes, it still holds true that larger bodies and those with more muscles burn more calories.)

Researchers also found our metabolisms go through four distinct stages through the life course.

From birth until age one, our metabolisms speed up. A 1-year-old’s metabolism is at its peak rate – about 50 percent above the standard adult rate. (Of course, this doesn’t mean 1-year-olds eat 50 percent more food than their parents, because their bodies are smaller they require less energy.)

From ages 1 to 20, our metabolisms gradually slow by about 3 percent a year. Then, starting at age 20, our metabolisms hold steady until age 60. (Remember, metabolism still fluctuates based on body size and muscle mass, just not based on age.)

After age 60, metabolisms do start to slow, by about 0.7 percent a year. This results in approximately a 20 percent overall decline by age 95. A 95-year-old will need about 20 percent fewer calories than she did when she was 60, assuming her weight and muscle mass don’t change much.