Maybe you’ve mastered making better-for-you Italian food, or tackled the fine art of outsmarting a craving. Heck, maybe you’ve even made the gym a regular habit (kudos!). But if you’re over 40 and all of this feels like it’s to no avail, you’re not alone. In fact, there’s science behind your weight loss plateau.

“As we hit menopause and our oestrogen levels begin to dip, we’re more prone to gaining weight around the middle,” explains dietitian Amy Gorin. “Age itself also plays a role here—we lose muscle mass as we age, around 10% each decade after age 45, and while we’re losing muscle, we’re also likely to gain body fat.” Because muscle burns more kilojoules than body fat, that means we don’t need to eat as many daily kilojoules as we get older.

Due to these changes in our bodies, Gorin says you have to alter your diet and prioritise exercise—especially resistance training—to keep your metabolism humming along. To flatten your belly after 40, try these easy tips from nutritionists who want to see you succeed. (P.S. Grab those weights!)

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