As men age from 50 to 70, their testosterone levels drop more than 40 percent, causing them to become fatter, and less sexual, muscular and assertive and have smaller, weaker bones (7,11). Twenty percent of men aged 60-80 years have testosterone levels below the lower limit of normal. Giving testosterone to normal men over 65 years of age causes them to lose fat, principally in the arms and legs, and increase muscle and bone size, principally in the trunk (1,12). Testosterone is an effective treatment for depression in older men (13). A study in the American Journal of Psychiatry shows that men who are mildly depressed have much lower levels of the male hormone, testosterone, than men who are severely crippled by depression and men who have no depression at all (1a).
Men with low blood testosterone levels are at high risk for heart attacks (3, 2), even though testosterone pills lower blood levels of the good HDL cholesterol and increase a man’s chances of getting a heart attack. Men with the highest testosterone levels have the lowest blood insulin levels which prevents heart attacks (3). Insulin is necessary to keep blood sugar levels from rising too high, but it also can increase your chances of getting a heart attack by causing arteries to constrict, and making you fat by causing hunger and forcing your liver to make extra fat from the extra calories that you consume.
Testosterone injections can make older men with low blood levels of testosterone more interested in making love (4,5,6). The only reported significant side effect is an increase in the concentration of red blood cells that could cause clots. Two major theoretical concerns about prescribing testosterone to older men are that they may cause a heart attack or spread an existing prostate cancer. However, only testosterone pills have been shown to lower blood levels of the good HDL cholesterol and cause heart attacks. Testosterone injections and skin patches do not (8,9,12).
Testosterone gels such as Androgel or Testim are highly effective. Since they are absorbed through the skin, they bypass the liver and have not been reported to lower the good HDL cholesterol that helps prevent heart attacks.
Studies from Chicago Medical School (10) showed that men 60 to 75 years of age who take very low doses of the male hormone, testosterone, (25 to 50 mg) weekly for two years have lower blood cholesterol levels, less body fat and greater muscle strength. Their prostates did not enlarge and their PSA blood test did not rise. More research is needed, but older men who take testosterone, should take injections or patches, rather than pills, and have their prostates checked by physical exam, sonogram and a blood test called free PSA.
Side effects of testosterone include androgen-sensitive epilepsy, migraine, sleep apnea, polycythemia or fluid overload. Use of testosterone is banned in many sports competitions.