Good Question: Why Does Our Metabolism Change As We Get Older?

MINNEAPOLIS (WCCO) -- We can all probably relate to this one. As we age, it's easier for pesky pounds to sneak up on us.

Our metabolism isn't what is used to be. So why does our metabolism change as we get older? Good Question.

Debra Sheats is an assistant professor at St. Catherine University. The registered dietitian said between age 25 and 70, the basic need for calories declines by 20 percent.

"So if you think about that, every year we need a few less calories to keep going," Sheats explained.

If people keep eating the same amount, "you're going to gain weight," Sheats said.

That coupled with lifestyle changes as people age -- busier lives and not exercising as much -- leads to less muscle and more fat.

"The type of tissue that burns the most calories is actually muscle, and as we get older part of aging is that we lose muscle. The more we can exercise and maintain our muscle the higher our metabolic rate is going to be," Sheats said.

Sheats said those fad diets, and rapid weight loss, actually slows our metabolism.

"When we start eating again, regular food, we tend to gain weight," Sheats said.

Sheats said the key is to look at your calories coming in and then make a plan for exercise to balance out the caloric needs. Basically, to stay the same weight, you have to eat fewer calories, or make up for the slowing of our metabolism by exercising and maintaining muscle.