How do my caloric needs change with age?

Q: I'm in my 50s and I've heard that it's normal to burn fewer calories as you get older. Is this true?

You can think of burning calories as "the first step to being alive," said Herman Pontzer, professor of evolutionary anthropology at the Duke University. Food gives your body the fuel it needs to stay healthy, he said.

Your age, among several other factors, can a big effect on the number of calories you need. Maintain your body's weight and basic functions, Dr. Pontzer and other experts said.

Here's what you need to know.

How Your Age Affects the Calories You Burn

Your body size is the most important factor that affects your caloric needs, Dr. Pontzer said. “The bigger you are, the more calories you need.”

But your stage of life is also crucial, he added.

Babies and children, for example, need fewer calories than adults simply because they are smaller. But when you calculate how many calories they eat relative to their height, it's actually more than adults eat because they're growing and developing, Dr. Pontzer said.

< p class="css-at9mc1 evys1bk0">Being more physical activity also increases the number of calories you burn, said Anna Maria Siega-Riz, professor of nutrition and dean of the School of Public Health and Sciences at health from the University of Massachusetts at Amherst. She was the lead author of a 2023 report from the National Academies of Sciences, Engineering, and Medicine that estimated the caloric needs of people in the United States and Canada.

According to this report, an inactive 200-pound, 40-year-old man would need about 2,700 calories per day to maintain his weight and basic bodily functions. But if he were an athlete training for a few hours each day, he would need about 3,500 calories per day.

The same report estimates that from From about age 19, caloric intake needs "decrease" a little each year — to the tune of about 11 calories per year for men and seven for women, said Susan Roberts, senior associate dean for basic research at the Dartmouth Geisel School of Medicine.

A 170-pound woman who walks 60 to 80 minutes each day, for example, would need 2,450 calories per day at age 20 — at age 60, however, this would drop to 2,150, and at age 80, it would be 2,000.

This age-related decline in calorie expenditure is usually more noticeable in your 60s, Dr. Roberts said, and perhaps manifests as weight gain. or a less robust appetite. As you age, you tend to lose muscle and gain fat, which burns fewer calories, she said. And your brain – the body's most metabolically active tissue – naturally shrinks and requires less energy, she added.

It's also common for People become less physically active as they age, thereby reducing the number of calories they burn each day, said Dr. Siega-Riz.

You can estimate your own calorie needs using an online calculator. Just keep in mind that these calculators can only provide a general picture of what you should consume. Your actual needs will vary based on your daily activities, genetics and other factors, Dr. Siega-Riz said.

If you're wondering if you're consuming correctly amount, the best way to check is to weigh yourself every once in a while, Dr. Siega-Riz said. If your weight is relatively stable, then you are consuming an appropriate number of calories.

But for some people, hyperfocus on the scale can create or worsen anxiety. When it comes to food and weight, Dr. Siega-Riz explained, so only weigh yourself as often as you feel comfortable.

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