If you Google ‘Low T’ you will be swamped by commercial websites which will have you convinced in no time that you have this condition. Tired? Who isn’t. Muscles not what they should be? Sex drive not what it was? The solution according to these websites is simple: “Buy our testosterone.”

Don’t.

The problem is that, once you start using testosterone, you will stop making your own. Your hypothalamus will stop stimulating your pituitary gland, which will stop stimulating your testicles, which will shrink. Your wallet will shrink even faster. What you used to make for free, you now have to pay for. Forever. Take too much, and you might even grow breasts just to add to the joy of the experience.

The first step should be to determine if you actually have low testosterone. That means an assessment by a doctor who knows a bit about it (and who preferably does not own the website flogging the testosterone!) If your level is normal to start off with, it will do you no good to add more. It will probably cause you harm, and will certainly make you poorer.

In young men who underwent normal puberty, low testosterone is rare. The main cause of low testosterone in young men is the use of gym drugs, some of which will switch off your own sex hormones really quickly. This includes not only anabolic steroids, but the newer group called SARMS which are touted online as the ‘safe’ non-steroid alternative. Wrong. SARMs can switch your testosterone production off abruptly and completely. You might get big muscles, but small testicles and no sex drive.

For older men, testosterone can decline with age, but it is not like in women where, at menopause, sex hormones fall off a cliff. There are plenty of 80 year-old men whose testosterone levels are the same as when they were 20. A lot of the decline has to do with men gaining weight, losing fitness, and getting diabetes. Slim down a bit and get fitter and probably your testosterone levels will climb back up close to where they were before you got fat. But there are some men whose levels drop with age, and replacing testosterone by a daily gel or three monthly injections will usually improve symptoms.

Take home message. It is important to have an informed medical assessment prior to commencing testosterone replacement. And monitoring is required after, checking blood count, hormone levels, and prostate.