Remember when you could eat 15 chicken nuggets, a large milkshake and a large fry without gaining a pound? Your mom would look at you and say, "You won't be able to eat like that in your 30s!" Your mom was right! While 30-years-old isn't necessarily the year that your metabolism drops and weight suddenly appears around your waist, your metabolism does change as you age. Most people just notice it in their 30s for the first time!
Your metabolism is the biological process that turns the calories you eat and drink into energy. The faster the metabolism, the faster you'll burn through the calories. 30 is not the be-all-end-all number, because in reality, the biggest changes to your metabolism arrive around menopause. Your body goes through a hormonal shift over the course of your life, gradually slowing your metabolism, which makes it harder for your body to process and burn the calories you're eating.
"There are actual real hormonal changes that take place in our body that then affect the way we store fat and lose fat," Kristen Gradney, spokesperson for the Academy of Nutrition and Dietetics, explained to SELF. "Our metabolic rate actually decreases because of these differences in hormones."
Your hormones might be changing during your 30s and 40s, sure, but Gradney suggests that your lifestyle might actually be more responsible for your weight gain than the hormones. Eating out, rarely exercising and staying stagnant—whether at a desk, in a car, or on the couch—are all factors that could lead to your decreased metabolism.
So what's a girl to do?
As menopause looms on the horizon (or it's already hit!), consider upping your workout routine to something a little more challenging. Since your body is no longer burning through calories like it once was, you might have to put in a little more work to keep your body looking trim. Don't worry, we have amazing workouts you can do in the comfort of your own home or at the gym. Check them out here!
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"If you have good genes but don't exercise or eat right, there's still the risk that you could see that decline earlier," says Gradney. "The best thing to do is to remain physically active, maintain muscle mass and have a good diet. If you do those things, that progressive decline will be slower."