#5 Reason: Simple science

Simply put, we are bound to gain weight as we age, IF we do not arrest this shift in body composition from fit to fat through exercise and healthy eating. The shift in body composition is a question of muscle loss and fat gain. 

Let’s elaborate: As we grow older, we lose approximately one pound of muscle a year. Now, muscle burns energy more efficiently than fat. This means that by losing muscle, you’re essentially slowing down your metabolism. The more muscle you lose, the more weight you’ll put on with the same amount of food you’ve always eaten or the same amount of walking or cycling you’ve always done. So even if you’ve always eaten a 2000 calories a day diet, you’ll suddenly start putting on weight as your body is depleted of muscle through lack of the right physical exercise.

This isn’t even big muscle or gym-muscle. This is your natural musculature, your basic muscle pool; what you were born with and/or developed as an active child; what kept most of us within a good weight range right till our mid 20s. The minute a sedentary lifestyle sets in, this natural muscle begins to disappear. The inevitable result – weight gain in the late 20s that keeps escalating with every new decade.