Stories tagged testosterone


Curious langur
Curious langurCourtesy John Downer
Have you ever wondered why people honk at you .02 seconds after the light turns green? Or why some people take Connect Four a little too seriously? Well, it may be the length of their fingers. That’s right, the difference in length between your 2nd finger (or pointer finger) and your 4th finger (or ring finger) is thought to be an indirect measurement of testosterone levels you were exposed to during fetal development. The more testosterone, the longer your ring finger compared to you pointer finger.

In a recent study, researchers from the University of Liverpool and Oxford used this measurement to link aggressiveness in primates with the levels of prenatal testosterone in utero. They found that Old World monkeys tended to have a low 4th digit (4D) to 2nd digit (2D) ratio (i.e. their ring fingers were longer than their pointer fingers) and also exhibited aggressive, competitive, and promiscuous behavior. New World monkeys (like gibbons), on the other hand, along with Great Apes (like chimps and orangutans) tended to have a higher 2D:4D ratio. These species were found to exhibit much more cooperative and tolerant behavior. The results of the study have implications for our own social behaviors. We live in large multi-male, multi-female groups and are (usually) quite cooperative. This study, and more like it, could start to shed light on the origins of our sociality.

The use of digit ratio as a measurement of prenatal testosterone is not new, however. Many researchers have used it even in humans (we are primates after all) to try and predict various behaviors, aptitudes, and personal characteristics. For example, some of the traits suggested to correlate with low digit ratios (ring longer than pointer) include greater male fertility, assertiveness in women, and greater musical and athletic ability. These studies looked at the increased competitive nature brought out in individuals with exposure to high levels of prenatal testosterone.

So the next time someone cuts you off, just know it might be the case that their 4th digit is longer than their 2nd… so try to leave your 3rd digit out of it.


Rocky times for Rambo: Shown here on a promotional tour in 1988 for Rambo III, Sylvester Stallone readily admits that he used HGH and testosterone to beef up his body to look good in his latest Rambo film.
Rocky times for Rambo: Shown here on a promotional tour in 1988 for Rambo III, Sylvester Stallone readily admits that he used HGH and testosterone to beef up his body to look good in his latest Rambo film.Courtesy wikipedia
Unlike with professional baseball players, Congressional leaders won’t have to hold hearings on this. Sylvester Stallone is being totally up front and candid about his chemical use to prepare for his latest “Rambo” movie.

The 61-year-old movie star admits that he used human growth hormone (HGH) and testosterone to pump himself up for the new feature film. Regardless of the quality of the movie (and I think I’ll be passing on it even when it hits the dollar theaters), doctors aren’t giving him a thumbs up on that medical decision.

More government studies are being conducted on the use of these substances and they’re not ready of general use, many doctors warn. And past research has shown that HGH and/or testosterone use can increase your risks for diabetes, arthritis, heart disease and possibly cancer.

On top of that, HGH and testosterone are illegal for use in general fitness. Doctors must prescribe the treatments, and only after conducting tests that show a patient’s body is under producing the chemicals.

It’s illegal a lot of other places to, which Stallone found out in producing the movie. Australian officials fined him $10,000 last May when they found him bringing 48 vials of the substances with him into the country for on-location filming.

Through all of this, Stallone seems to have given some conflicting accounts of why he’s used the substances.

Dealing with the Australian legal authorities during court proceedings for possession of HGH and testosterone, Stallone said: “I made a terrible mistake. Not because I was attempting to deceive anyone but I was simply ignorant of your official rules and I wish to sincerely apologize to the court and the Australian community for my breach of Australian customs law. ... I have never supported the use of illegal drugs or engaged in any illegal activities in my entire life. ...I wish to express my deepest remorse and again apologize for my actions.”

But this month in Time magazine, he’s quoted as saying: “Testosterone to me is so important for a sense of well-being when you get older. Everyone over 40 years old would be wise to investigate it because it increases the quality of your life. Mark my words. In 10 years it will be over the counter.”

We’ve walked this path before a few times on the steroid debate over baseball player Barry Bonds. But here’s one more thing to mull over on this latest twist to chemical enhancements to the body. Researchers say HGH and testosterone can certainly make your body look stronger, especially in the way that they help reduce body fat content to give muscles a more “ripped” look. They also allow muscles to recover faster from intense workouts. But there’s no data that says that they’ll make muscles stronger or performer better when being used.

So is it really worth all the medical risks? Is it worth breaking the law to look good? Share your thoughts here with other Science Buzz readers.