How do your calorie needs change as you age? Experts explain

Experts say your age — among several other factors — can have a big impact on how many calories you need to maintain your weight and basic body functions. Your body size is the most important factor that affects your calorie needs. “The bigger you are, the more calories you need,” said Herman Pontzer, a professor of evolutionary anthropology at Duke University in the United States.

Life stage is also important, he adds. Children and infants, for example, need fewer calories than adults simply because they are smaller. But when you calculate the number of calories they use compared to their body size, it is actually more than adults because they are growing and developing, the expert explains.

Getting more physical activity also increases the number of calories you burn, notes Ana Maria Ceja Reyes, a professor of nutrition and dean of the School of Public Health and Health Sciences at the University of Massachusetts Amherst. She was the lead author of a 2023 report by the National Academies of Sciences, Engineering, and Medicine that estimated people’s calorie needs in the United States and Canada.

According to this report, a 200-pound, inactive 40-year-old man needs about 2,700 calories per day to maintain weight and maintain basic body functions. But if an athlete trains a few hours a day, he or she will need about 3,500 calories per day.

The same report estimates that starting at age 19, calorie needs “decline” slightly each year, amounting to about 11 calories per year for men and 7 calories for women, explains Susan Roberts, senior associate dean for basic research in Dartmouth’s College of Science. . Medicine Geisel.

For example, a 70-kilogram woman who walks 60 to 80 minutes a day needs 2,450 calories a day at age 20 – but by age 60, this number will drop to 2,150, and by age 80 it will be 2,000.

This age-related decrease in calorie burning is generally more pronounced after age 60, and may manifest as weight gain or a less robust appetite. As you age, you tend to lose muscle and gain fat, which burns fewer calories, Roberts explains.

The doctor adds that your brain – the most metabolically active tissue in the body – naturally shrinks in size and requires less energy.

It’s also common for people to become less physically active as they age, which reduces the number of calories they burn daily, Ceja-Reese says.

There are some calculators online that help you estimate your calorie needs. However, it only provides an overview of what you should consume. Your actual needs will vary depending on your daily activities, genetics, and other factors.

If you are wondering whether you are consuming the right amount, the best way to check is to weigh yourself every now and then. If your weight is relatively stable, you are eating enough calories.

But for some people, focusing too much on the scale can create or exacerbate anxiety about food and weight. So, only weigh yourself as much as you feel comfortable.

Eating habits and low calorie burning

The good news is that you probably won’t need to count as many calories as you get older because, according to Pontzer, your appetite should naturally decline to meet your needs.

But as you age, it’s important to make sure you get the right balance of nutrients. For example, research suggests that starting around age 50, your body needs more of specific nutrients, such as calcium, vitamin B6, vitamin D and protein, even though you may be eating fewer daily calories overall.

For this reason, you’ll need to allocate more of your daily calories to foods that provide a greater nutrient return, such as fruits, vegetables, whole grains and lean protein sources.

For Roberts, when you’re in your 20s and 30s, “you can still get extra calories from chocolate, beer or a piece of cake.” But if you’re in your 80s and only consume about 1,500 calories a day, there’s less room for sweets.

The doctor also recommends that seniors take multivitamin supplements to help fill any nutritional gaps. But despite this, a good diet is still essential to ensure you get other important nutrients such as protein, fiber and healthy plant compounds.