1.   He snatched a medical book on geriatrics, and there he saw another chart listing the many painful effects of normal human aging.

2.   Now studies suggest low dopamine may be part of normal aging, especially in men, and may play a role in memory loss.

3.   The gene, which was identified among families in Japan and Syria, may shed light on the process of normal aging.

4.   This kind of growth affects an estimated one in six American women, and may be caused by heredity, normal aging or medical conditions such as hormone imbalances.