Does Your Metabolism Betray You

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I don't mean to brag, but I am down 39 pounds as of this recording! I feel great! It's part of my goal to get healthy. But losing weight is as much fun as playing in traffic. It's hard enough without all the diet myths out there, so we're shredding one of them today.

A new study refutes the idea that our metabolism drastically slows as we age. It followed over 6,000 people across about 30 countries ages eight to ninety-five. People in the study drank water with non-radioactive "heavy" atoms of hydrogen and oxygen. Scientists measured their urine for the amount of these atoms. It's a simple and incredibly precise way to tell how well we're burning calories.

Yes, we do burn more calories when we're young however not in the way you think. Up until age 1, babies burn calories 50 percent faster than adults. As you grow, the rate slows 3 percent a year until age 20. That's right, then it stays steady until age 60! So, when a friend who's 45 says he can't lose weight because his metabolism is shot, you can enlighten him.

After age 60, the study found that metabolism only decreased 1 percent a year. There's no impact from menopause and no changes between women and men when body size is accounted for. So, why do we gain weight in middle age? It may be changes in activity level, sleep, and amount of food eaten. These are behavioral which means we have some control over them which is good news even if we are taking away people's excuses.

More Information

What We Think We Know About Metabolism May Be Wrong
A new study challenges assumptions about energy expenditure by people, including the idea that metabolism slows at middle age...

Metabolism in adulthood does not slow as commonly believed, study finds
Metabolic rate remains stable all through adult life, from age 20 to 60 years old...

Daily energy expenditure through the human life course
Measurements of total and basal energy in a large cohort of subjects at ages spanning from before birth to old age document distinct changes that occur during a human lifetime...