Study Sheds New Light on Metabolism
Most of us remember a time when we could eat anything we wanted and not gain weight. But a new study suggests our metabolic rate, the rate at which we burn calories, actually peaks much earlier and begins to decline later than we think.
These findings appear in the journal Science. Using data from nearly 6,500 people, ranging in age from 8 days to 95 years, researchers discovered that there are four periods of life, as far as metabolism goes. The team also found that there are no real differences between metabolic rates of men and women after controlling for other factors such as race, puberty, menopause, and phases of life.
The study authors refer to the speed of metabolism as “four distinct life stages.” Here’s what they are:
• Infants up to one year old (50% faster metabolism than adults)
• Then from age 1 to about age 20, metabolism gradually slows by about three percent a year
• Adulthood (20 to 60 years), metabolism remains stable
• After age 60, metabolism declines by about 0.7% a year
The data suggest that metabolisms don’t really start to decline again until after age 60. But people in their 90s may need fewer calories each day than someone in midlife.
According to the study published in Science, middle-aged spread cannot be blamed on metabolism.
Pontzer H, Yamada Y, Sagayama H, Ainslie PN, Andersen LF, Anderson LJ, Arab L, Baddou I, Bedu-Addo K, Blaak EE, Blanc S. Daily energy expenditure through the human life course. Science. 2021 Aug 13;373(6556):808-12.