If you're genetically predisposed to gain weight easily, that may be another strike against you. Even if you don't actually gain weight, you may still gain inches around the waist. This weight gain can be so frustrating, it's easy to become obsessed with losing it, starving yourself or exercising too much or maybe even looking into the latest plastic surgery procedure.
Even if you’re eating reasonably well, you can still be in a calorie surplus. Whether you’re eating oversized portions, taking mindless bites while prepping family meals or grazing as part of a new work-from-home norm, all that noshing adds up. Tracking your food intake can be helpful. In one 24-week study, researchers found that time spent logging food intake was significantly linked to weight loss. If tracking your food (even with an app) sounds daunting, consider that by the end of the study, those who were still committed to tracking spent just 15 minutes a day doing it — about what you might spend scrolling through Facebook or Instagram.
Your metabolic rate naturally continues to decline 5 percent each decade once you hit 40.3 Your resting metabolic rate (RMR) determines how many calories you just to survive. It is determined by a variety of chemical reactions inside your body. These reactions rely on your mitochondrial function and sodium-potassium pumps. Your mitochondria help to create energy, while your sodium-potassium pumps generate muscle contractions and nerve impulses.4,5,6,7,8 Both of these processes become less effective over the years and slow your metabolism.9,10 If you eat more than your RMR yet lead a sedentary life, you set yourself up for weight gain.
Hormonal changes are one of the main reasons that women tend to lose more muscle as they approach menopause. Diet and exercise also play a role.12 On average, adults lose 3 to 8 percent muscle every decade after age 30.13,14 By the time you reach 80, you may have about 30 percent less muscle than you had at age 20.15,16 Muscle loss over time can lead to slower RMR, increased fat, weight gain, weakness, and fractures.17
One of the main culprits for weight gain is, of course, our hormones, which start to change right around the mid-30s and into the 40s. This change in hormones, less estrogen for women and less testosterone for men, cause the fat in our bodies fat to shift to the middle of the body while abandoning other areas of the body you could care less about. That's one reason you may get a little fluffier around the middle while other parts of you actually get smaller.