The purpose of anti-aging medicine is to raise quality of life (QOL) and to aim at healthy longevity. Melatonin, DHEA(-s) (dehydroepiandrosterone [sulfate]), somatotropin/IGF-I (insulin-like growth factor-I), male and female hormone decrease with aging, that can be prevented by hormone replacement therapy. This therapy has two sides of supplement of the deficit and a healthy increase. Hormone age is "the function age that expressed whether you are equivalent to a hormone secretion state of how old average" and 30 years old or 70-80% of chronological age regard the targeted value of hormone age. We do not decide quantity of hormone replacement uniformly. The reasonable quantity should be determined based on each figure, active mass, life level, and/or blood levels of hormones. Data accumulation for a long term in multiple institutions is important.