InformationMany people are concerned with changes in their body shape as they age. Although some changes inevitably occur with aging, your lifestyle choices may slow or speed up these changes.The human body is made up of fat, lean tissue (muscles and organs), bones, water, and other substances. As we age, the amount and distribution of these materials will change.Fat tissue may increase toward the center of the body, including around the abdominal organs. The amount of body fat may increase by as much as 30%.As fat increases, lean body mass decreases. Your muscles, liver, kidney, and other organs may lose some of their cells. This process of muscle loss is called atrophy. Bones may lose some of their minerals and become less dense (a condition called osteopenia, or at its later stage, oste