The maximum life span known for humans is 122 years, whereas the maximum lifespan of a mouse is about 3 years. There are many reasons this happens, genetic differences between humans and mice, fertility rate, efficiency of DNA repair and the old “buzzword” different rates of free radical production, etc. Antioxidants, including Vitamins A, B-6, B-12, C and E are believed to counteract free radicals and in some way prevent chronic disease such as heart disease and diabetes. There are many studies that point towards the benefits of beta-carotene, folic acid and selenium. These anti-oxidants are found in a variety of fruits and vegetables. I suppose as a scientist, I am cynical about the advantage of these adjuncts in pill form.
Regarding hormone use, I am going to stand out on a limb and look at the evidence supporting their use. When people talk about hormones, they usually mean taking DHEA, Testosterone, Oestrogen and probably Human Growth Hormone. Hormones are chemicals needed to help keep your vital organs working properly, which decline naturally as we age. It is easy to see why people would believe restoring their level to lead to previous levels. Unfortunately, life is never that simple. We all know that HRT can restore a woman’s skin, vaginal secretions, energy etc. but it has its risks in older age groups also. Look at the precursor hormone DHEA, which is converted in the body to oestrogen and testosterone. DHEA has long been touted as an anti-aging therapy, used to ward off chronic illness and maintain energy and vigour. Proponents say it also slows aging, increases muscle and bone strength, burns fat, improves cognition and bolsters immunity. However, an October 2006 study published in the New England Journal of Medicine by Sreekumaran Nair, M.D., an endocrinologist at Mayo Clinic, Rochester, found no evidence that taking DHEA reverses the effects of aging.
DHEA is the most abundant naturally occurring hormone circulating in the human body. It is secreted by the adrenal glands and reaches its peak by the early twenties and then declines with age. The decline with age of DHEA levels correlates with many age-related changes, including peaking at games, of muscle mass, of bone density, physical endurance and ability to fight disease. The study significant beneficial effects on any of those factors in men and women in their 60s and 70s. I don’t mind standing out on a limb on some issues but not this one as I don’t really know. I expect not as its use is regulated by the FDA in the United States. This hormone is extensively promoted and used as an anti-aging nutrient supplement by people hoping it will restore the pleasure of youth or increase longevity. I expect, science does not support its use, although I am sure there are many people who would disagree with me on this one. The increasing use of testosterone is also one to watch. The male menopause, does it really exist? We do know for many years that declining levels of testosterone have been linked with decreased energy and sex drive, decreased muscle mass, decreased mental ability and even osteoporosis. We also know that more and more men are taking testosterone but not enough is known about the long term effects of testosterone therapy for this purpose.
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