5 Testosterone Myths

Thanks to stories about doping athletes, the words "testosterone" or "anabolic steroids" create unsavoury associations. However, testosterone is a key hormone that has numerous important and beneficial functions in men. In fact, if it weren't for testosterone, all little boys would be born with a labia instead of a scrotum! In adults, testosterone is important for normal sexual function, sperm production, as well as muscle development and tone. In my work as a urologist at Men's Health Boston, I treat men with infertility (i.e., vasectomy reversal) and sexual problems. Many of these men are diagnosed with low levels of testosterone, or what I call "low T."

Low testosterone can also cause chronic fatigue, depression, and reduced muscular/athletic performance. Treatment with testosterone can improve erections and sex drive, restore muscle and reduce fat, and increase energy and motivation. I have written a book, Testosterone for Life (McGraw-Hill), to help men figure out if they have low testosterone, and if so, how best to obtain treatment. New evidence suggests that normal testosterone levels are important for reducing the risk of diabetes and cardiovascular disease, and men with normal levels live longer than men with low T. However, stories about cheating athletes and muscle-crazed bodybuilders have given testosterone a bad name, and have created a number of myths. Here are five of the most common testosterone myths.
1- Testosterone is an illegal drug
Nope; testosterone is a perfectly legal prescription medication. It is also a key hormone present in every man that is responsible for fetal development of the male genitalia, the physical changes that occur during male puberty, and that contributes to a variety of functions in the adult man including sperm production, erections, sex drive, muscle tone, and bone health, among others. Testosterone is only illegal when it's used without a physician’s prescription. However, many sports organisations have strict rules regarding substances such as testosterone that may influence athletic performance. Athletes who violate the rules of their sport are cheating, and lying about it to Congress may lead to prison time.
2- Testosterone is a steroid, and steroids are dangerous
Testosterone is a steroid, but that doesn’t make it dangerous. In fact, we’re all naturally loaded with various kinds of steroids. The word "steroid" simply refers to a molecule with a “backbone” of four rings of carbon —  examples include estrogen, progesterone, cortisol, and even cholesterol. Clearly, when an athlete tests positive for “steroids,” no one is concerned that he injected himself with cholesterol. In the sports world, the word “steroid” is shorthand for an “anabolic steroid hormone,” meaning steroids that specifically act to build muscle and bone, like testosterone. Whereas testosterone has been shown to be relatively safe, even at high concentrations, there is almost no information at all about the safety of the newer “designer” steroids produced to escape detection in drug testing.
3- Testosterone causes uncontrollable violent behaviour
There is absolutely no reliable evidence that testosterone causes “’roid rage” or any type of violent, aggressive or uncontrollable behaviour. No violence, aggression or unpredictable behaviour has been seen in studies where men were administered testosterone, even at extremely high doses. In fact, the opposite appears to be true; many men with low testosterone describe being more irritable, or having a short fuse, and this often improves with normalisation of testosterone levels. A recent patient treated with testosterone told me that his wife found him “unbearable” to be around before he was diagnosed with low T and subsequently treated; “I’m a nicer guy now,” he said.  
4- Testosterone causes prostate cancer
New evidence conclusively shows that men with higher levels of testosterone are at no greater risk of developing prostate cancer than men with low testosterone. Moreover, treating men with testosterone has not been shown to cause any increased risk of prostate cancer either. The basis for this myth originated from studies in the 1940s in which men with metastatic prostate cancer showed benefits when they were castrated. It appears that the only men at risk for prostate cancer growth with higher testosterone are men who have already been castrated. An exciting, but controversial, development is the use of testosterone to treat symptomatic men with low testosterone who have undergone prior therapy for prostate cancer (I have a special chapter on this in my book, Testosterone For Life).
5- Higher testosterone causes baldness
On average, men with male pattern baldness have the same testosterone levels as men with a full head of hair. Baldness seems to be genetically determined. The confusion arises because medicines like finasteride (Propecia) that block conversion of testosterone to dihydrotestosterone (DHT) can prevent or treat baldness. Since only very small amounts of DHT are needed by the scalp to do what the genes tell them to do (in this case, lose hair), men who are pre-destined to pull a Kojak will do so whether their testosterone concentrations are high or low.