Hormone levels in the body control hair growth and loss on a man's leg. Each hair follicle has its own individual sensitivity levels to these hormones, allowing different parts of the body to grow or lose hair at different rates.
Diabetes, lupus and other diseases and fungal infections that disproportionately affect the elderly may cause hair loss. Some diseases and infections that cause hair loss can be easily treated. A doctor should be consulted if you suspect hair loss on the legs may be due to an illness or infection.
Some medications prescribed for high blood pressure and heart problems can cause hair loss on the legs, body and scalp. Normal hair growth returns if use of the medication ceases.
Major surgeries for men in their old age puts stress on the body that can cause hair loss. This can occur many months after a surgery as the body recovers from the stress.
An overactive or inactive thyroid gland may cause hormone levels to fluctuate as men age, causing hair loss across the legs, body, and scalp. Hormone treatments can alleviate this hair loss if the problem is deemed severe by a doctor.
Chemotherapy or radiation treatments can damage the hair follicles of ageing men. Hair loss may be noticed 10 to 14 days after treatment begins and can continue until as much as a month after cancer treatments have ended. Normal body hair usually grows back completely within six months to a year.