by Marc Richman, M.D.
Testosterone deficiency syndrome (TDS, or Low T), as its name implies, is a medical condition in which a man’s level of testosterone, the male hormone, is insufficient. Low T can cause a variety of problems: sexual dysfunction, fatigue, lack of motivation, loss of vitality and difficulty building muscle mass.
A specialist can diagnose Low T only after taking a man’s detailed medical history, conducting a physical exam and measuring the testosterone in his blood. That last factor, expressed numerically, typically leads to a variety of questions: What constitutes a normal testosterone reading? Is there an optimal time of day to measure it? Which of the three types of testosterone — free, total or bioavailable — is the best to measure? Do T levels vary among age groups? Do some men need more of the hormone than others? How much is enough? Can one’s levels be too high?
Some of these questions have simple answers; others are extraordinarily complex — and even expert medical opinion varies widely on some of them. In practical effect, you see, testosterone is just a number — a number that in some cases we don’t understand all that well.
There are further complicating factors, too: As a hormone, testosterone must bind to a receptor on the surface of a cell. Once that receptor is activated, a series of cascading biological reactions must then occur before a man’s cell physiology is altered — that is, before an accurate testosterone reading is possible. What happens, then, if a man’s T level is fine but the cell receptor or one or more of the ensuing cellular reactions is dysfunctional? In cases like this, a testosterone reading might not tell us much at all, given that measuring receptor function and the concomitant cellular activity is impossible.
All of this helps explain why it’s so important to focus on the patient as a whole, not just his testosterone level. True experts in the field recognize this and govern their treatment accordingly: Some men exhibit Low T symptoms even when their test results are normal. Some will have low testosterone yet feel fine. Others will indeed need testosterone treatment to function normally. Yet none of this can be determined by a T reading alone, and a physician who uses that number as a guide, not a dispositive diagnostic — and who treats the whole patient, not just his hormones — is a physician who will achieve far better results for the men in his care.