Men can gradually lose an inch between the ages of 30 to 70, and women can lose about two inches. After the age of 80, it's possible for both men and women to lose another inch. Why do we shrink as we age?

At what age does a man start slowing down?

Some of the changes of aging start as early as the third decade of life. After age 25–30, for example, the average man's maximum attainable heart rate declines by about one beat per minute, per year, and his heart's peak capacity to pump blood drifts down by 5%–10% per decade.

What age does the human body start to deteriorate?

Some systems begin aging as early as age 30. Other aging processes are not common until much later in life. Although some changes always occur with aging, they occur at different rates and to different extents. There is no way to predict exactly how you will age.