Aging is nothing more than a
disease state. Aging starts when cell death starts, as early as age 25.
From ages 25 to 35:

Most hormone levels start to decrease. Growth hormone level has already fallen approximately 14% by age 35.
Poor diet, stress and environmental pollution cause free radical formation and cellular damage. While you may look and feel good, internal
cellular damage is already happening.
By age 45,
production of many hormones has fallen by more than 25%. Internal
cellular damage by free radical continues. Signs and symptoms of aging such as decreased visual acuity, graying of the hair, increased pigmenting of the skin and decreased strength and energy are making their presence felt on the outside. The nails are brittle, the breath is short and gone with the libido. The prostate gland hypertrophies and the trips to the bathroom at night increase. If not controlled or slowed,
mutational changes may lead to cancer.
At age 45 and above, most
hormone production continues to decline, including growth hormone, DHEA, Melatonin, and male and female sexual hormones. The rate of
decline accelerates as we get older. Signs and symptoms of aging worsen. The skin is further dehydrated and thinned as collagen fibers break
down to form wrinkles. Painful arthritis sets in. Fatigue and loss of energy follow.
As organs begin to fail, chronic illnesses such as hypertension, diabetes, cardiovascular disease and Alzheimer's disease appear.
As our cells succumb to assaults, mutation and cancer can arise.
Look out tomorrow for the current theories on why we age.