Sometimes the medicines you're taking for other issues, such as high blood pressure and antidepressant meds, can increase your weight or keep you from losing it, says Dr. Stanford. Ask your doctor if your weight concerns could be side effects of the prescriptions you're getting filled. Often, there are other formulations that can be effective but wouldn't have those side effects for you.

Very soon, I’ll stand up in front of the graduating class of my former high school and give the commencement speech. I’ll focus on the usual “work hard” and “follow your dream” themes, but, in reality, I just want to shout out to all those 17-year-olds — “have that ice cream cone, you’ll still fit into your skinny jeans tomorrow! ” Or “it’s OK to skip a workout, your muscle mass will help you bounce back!”
To jumpstart your weight loss, the biggest focus should be to develop habits that will help you build or maintain your muscle mass. "The most effective way that women over 40 can boost their metabolism is by building muscle through weight-lifting and resistance training," says Dr. Peterson (more on that to come). But nutrition and sleep habits also play a role here.
It’s usually not just due to losing muscle mass over time (more on that later). "It's multifactorial," says Fatima Stanford, MD, MPH, obesity medicine physician scientist at Massachusetts General Hospital and Harvard Medical School. Numerous factors can sneak up on you and help you gain or hold onto weight, including your lifestyle, your food, your biology, and your sleep habits. The good news in that is that there are also numerous ways to tackle getting your weight to where you want it—you don't have to force yourself into one approach, and you get to choose what works for you.
"One of the reasons that it's difficult to lose weight in your 40s is that you are beginning to lose muscle mass, so the composition of your body tissue changes," explains Keri Peterson, MD, Women's Health advisor. "Having higher muscle mass raises your metabolism, so your body burns more calories." So when you're dealing with the opposite—less muscle mass—that means a slower metabolism. Argh.
Starting in your 30s, you can lose three to five percent of your muscle mass each decade if you don’t stay active. Note the last part of that point: “If you don’t stay active.” As you get older, "there's a lot of competition for your time and energy," says Dr. Yancy. For some men, that can push exercise out of the picture. But it doesn't take heroic efforts to put it back into your life.

When you were young, you probably didn't spend too much time thinking about preparing your body for the future. In your teens and twenties, you're in peak condition and it's the perfect time to start exercising. Cut to 20 years later and, if you didn't start exercising, you probably wish you had since there's something we all start to experience in our 40's—weight gain.

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