If you prefer a specific plan with specific rules, make sure it goes with your lifestyle, which, for most guys, gets increasingly complicated in your 40s with more responsibilities at work, with your family, and maybe even with your aging parents. A vegan diet can be hard to do in a healthy way if you live a grab-and-go existence. Meal prep is going to be a challenge if you’re never home long enough to cook. Don’t just pick what worked for a friend; pick what’s likely to work with your busy, over-40 lifestyle.
“To achieve and maintain a healthy weight as we age, it’s imperative that we incorporate a ‘movement portfolio’ into our daily lives,” said Kushner. He explained that your portfolio should include activities of daily living (like walking, using the stairs and house cleaning), active fitness activities (like bike riding and using the elliptical machine) and resistance-training exercises. Kushner also recommended trying to reduce the time you spend doing sedentary activities like watching TV. “These targeted action steps will boost metabolism and help maintain muscle mass,” he said.
Your body has to work harder (meaning it burns more calories) digesting protein than it does fat or carbs, so Palinski-Wade recommends the strategy of upping protein intake to many of her clients, including women who are 40 and over. "Although I don’t promote very high-protein diets, increasing your protein intake from 15 percent of your total calories to 30 percent can help you boost the calories your body burns during digestion, which may just help speed weight loss."
People naturally lose muscle after 40, especially women after menopause. Because muscle burns more calories than fat, this can slow down your metabolism and make it harder to shake those stubborn pounds. Strength-training exercises -- lifting weights or doing body-weight exercises, like push-ups and squats -- at least twice a week can help you keep those muscles.