The days of gorging without gaining weight are over. And as your metabolism slows around age 40, eating fewer calories can boost health. But you should also make sure to get adequate fiber and fluids. Make sure the calories that you are decreasing come from things like sweets, but we keep those high-fiber foods in the diet, and we also make sure we meet our fluid needs. That’s really important. Make sure that our daily eating plan is packed full of nutrient-dense food, like lean protein, fruits and vegetables and low-fat dairy and whole grains.