Why you’re gaining weight in midlife, even though you’re not eating differently

It’s a common frustration among women 40-plus: “Why am I gaining weight? I’m not eating any differently than I did in my 20s!” Unfortunately, that’s exactly the problem. Your metabolism changes as you get older, which means your lifestyle habits need to as well.

Your incredible shrinking metabolism

When you’re younger, your metabolism is more efficient. You can break down and utilize all types of foods without it having a huge impact on your waistline. But as you get older, your metabolism slows down. In the beginning, it’s not that noticeable. From age 20 to age 30, the decline is only about 1 to 2 percent. But around age 40 or 50, it takes a real nosedive.

Why this sudden shift? There are several reasons, but a big factor is your hormones.

Your hormones and your metabolism

Your basal metabolic rate — the amount of calories your body burns just keeping you alive and functioning — is regulated by your hormones. As you age, hormonal changes cause your body to burn less fat and store more. One big culprit? Estrogen. With menopause, levels of estrogen plummet, and your metabolism goes right along with it.

But there’s another hormone that may have an even bigger influence on your body’s penchant for storing fat as you age: insulin. Insulin is the body’s fat storage hormone. When insulin levels are high, your body deposits fat in your liver and belly.

America’s insulin problem

So what makes insulin high? Sugar. But it’s not just table sugar that will make your insulin spike. Anything you eat that is quickly broken down into sugar, from cookies to white rice to chips, will raise insulin levels. If you regularly eat high-glycemic foods — foods that cause your blood sugar to surge soon after eating them — your insulin levels will stay high. And when your insulin levels are consistently elevated, your body will consistently store fat.

What to do about it

The good news is, most people can pretty easily bring their insulin level down — and therefore burn more fat — by making simple dietary changes.

  • As a rule, say no to foods that are obviously high-glycemic, such as desserts, soda, and fruit juices. Save those for special occasions.
  • Avoid foods that are sneakily high-glycemic, like white rice, white pasta, white bread, potatoes, pizza, and most processed foods.
  • Follow the salad plate scenario, and fill your plate with 50% vegetables, 25% protein, and 25% everything else at each meal, being sure to liberally use good fats in cooking and throughout your meal.
  • Move your body! Exercise stabilizes insulin levels for up to 16 hours after you stop and helps mobilize fat. Aim for 30 minutes every day, even if it’s something as simple as a brisk walk.
  • Manage your stress. Chronic stress causes levels of another hormone, cortisol, to rise. And like insulin, cortisol also cues your body to accumulate belly fat.
  • Safeguard your sleep. Skimping on sleep messes with your appetite hormones, making you feel hungry even when your body doesn’t actually need food.

Are you over 40? Have you noticed a change in your weight? Let us know about your struggles in the comments below.