"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.
I am 59 and have been on a injury / weight gain cycle for several years. I have never been overweight till my first accident , then I gained weight and kept gaining and now that I am almost 60 , I want that great body and high energy back. The older I get the more problems my weight causes , legs hurt , falling asleep in my chair , I am too young for that. So I am eating better and boxing , which is a great workout . I plan to sky dive for my 60th next year.
In your forties, your body may have an increasingly difficult time digesting carbohydrates, which may lead to weight gain. Living a stressful life can lead to an increase in the stress-hormone called cortisol, which can make you more prone to gaining belly fat. Estrogen loss may also lead to fat redistribution in your body and cause belly fat gain.11
Additionally, attempts to lose weight on low-calorie diets can lead to even more lost muscle. Studies have found that regular resistance or strength training may be a better alternative than your daily runs to preserve and gain muscle — even when coupled with a low-calorie diet. Aerobic exercise is still important, just don’t make it your only form of activity.
It's a myth that eating at night leads to weight gain, Palinksi-Wade points out; it's more about what you're eating at night that can be an issue when it comes to weight management. "Since most of us don’t have a salad for a midnight snack, if you find you tend to eat calorie-dense, high-sugar foods in the evening (like a bowl of ice cream) setting guidelines as to when to stop eating may help you to lose weight faster."
If you eat healthy and exercise regularly and still can’t lose weight, your thyroid might not be working like it should. This happens in about 5% of people, and it's most common in women and people over 60. In addition to weight gain, it can also cause fatigue, joint or muscle pain, and depression. Medications can help, so get it checked if you think it might be an issue.