About Hormones Men Testosterone and Aging
What happens to testosterone levels as we age?
The trend in the non-medical media is to rephrase that question to make it “catchy” and as familiar as menopause. Even many anti-aging practitioners do the same. So you’ll see the question headlined on the covers of men’s health publications: Is there a Male Menopause? To be totally accurate, the answer is ‘No’ because there is no universal point in the life cycles of normal, healthy men that testosterone levels sharply and suddenly drop to less than 20% of their youthful levels. It is pretty universal that around age 51, this occurs with most women’s estradiol levels. Regrettably, many doctors use that very difference as grounds for their argument that because the testosterone decline is not abrupt, treatment for men isn’t as necessary as it is for women in menopause. At OptiGenics, we think that rationale is faulty. There is now a robust body of scientific data on the effects of aging on testosterone levels. Let’s look a little more closely...
The Massachusetts Male Aging Study was one of the largest studies to examine testosterone levels in aging men. Researchers found that total testosterone levels declined by about 5% per decade from age 30 to well in the 70s. Steeper declines were found in men who were ill or obese. Still in some men there wasn’t much decline at all. For decades this produced a setback to general acceptance for TRT as an anti-aging treatment. Many physicians simply didn’t think there was enough decline to require treatment. But what they didn’t value enough was the decline of free testosterone levels.
Free testosterone is the most biologically important part of testosterone levels and it declines twice as fast, about 10% per decade. This would indicate that some 50% of men over age 55 have ‘hypogonadism’ when it is defined as free testosterone levels below the lowest normal range in young men. Consequently, many well-designed and more recent studies have validated those numbers. It is widely agreed in endocrine research and literature that testosterone levels decline in men over time and often to a point, equal in effect, to menopause in women. (Do remember the reason total testosterone does not drop as steeply with age: there is an increase in ‘sex hormone binding globulin’ (SHBG) with age. The increased SHBG offsets waning testosterone production.)
When studying declines in absorbable testosterone and if it shows a relationship with signs and symptoms of aging, Dr. John Morley observed 54 men between the ages of 20 and 84 years old. He wanted to see if the bioavailable testosterone level (the rate of absorption of the hormone) could predict which men would have declining intellectual and physical functioning. As have many subsequent studies, Dr. Morley's found a strong correlation.
To conclude, we can now most assuredly say that testosterone levels decline with age and that this decline is partially responsible for some of the important signs of aging. Other factors (obesity, chronic illness, and stress) can be very important factors as well, but if one places proper controls on the studies of these elements, age is the factor still associated with very steep and significant drops in testosterone.
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