Do steroids increase aggression, or is the apparent aggressiveness of steroid users simply a result of competitive gym rooms and the personalities of the bodybuilders who use them?
That question has troubled researchers ever since the use of anabolic-androgenic steroids (AASs), such as testosterone, first became popular among bodybuilders in the 1970s. In animal models, the relationship between AASs and aggression is clear; in some studies, more than 80 percent of steroid-treated animals become extremely aggressive. In humans, however, the picture has been clouded by alternative explanations and a lack of hard evidence. Only in recent years have researchers been able to confirm that steroid-induced aggression--colloquially known as "roid rage"--is a real phenomenon that can occur in individuals who take large doses of steroids for extended periods of time.
At the same time, new animal research is raising questions about the effect of teen-age steroid abuse on the development of brain systems that influence aggression. Northeastern University psychologist Rich Melloni, PhD, has shown that AASs can alter the distribution of neurotransmitters in the brains of adolescent hamsters. Together with signs of increasing steroid use among certain demographic groups, such research has spurred concerns about steroids abuse's long-term psychological consequences.
"The adolescent stage of childhood is a very vulnerable time in terms of aggression," says Melloni. "That's when the circuits in your brain that are responsible for impulse control are developing at a very high rate. So, by taking steroids, what you're doing is affecting the development of this system that inhibits your aggressive response, and that's going to predispose you to violent outbursts."
Melloni notes that the link between normal variations in testosterone level and aggression is weak; a strong correlation is found only when considering the abnormally high levels reached by steroid abusers. "In humans, there is a normal range, and whether you're on the high side of that range or the low side of that range, the clinical data is very poor for a link between testosterone and aggression," he explains. "But studies are clear that superphysiological doses, very high doses, stimulate aggression."
Harvard Medical School psychiatrist Harrison Pope, MD, has provided some of the strongest evidence that human steroid abuse can boost aggression. In 2000, he published a double-blind, randomized study confirming that high doses could increase aggression even in men who were not bodybuilders. The study also showed that individual reactions could vary dramatically even under tightly controlled experimental conditions.
"These reactions to steroids cannot be explained purely by premorbid personality characteristics or expectational factors," says Pope. "There must be an actual biological phenomenon that occurs in some people. But which people? We don't know. The majority of men who take steroids don't experience problems, but the occasional person will have a very severe reaction."
The difference between aggressive and nonaggressive users may lie in part in the particular steroids they are taking. Testosterone and its synthetic derivatives appear to facilitate aggression, but other steroids may actually inhibit it, says Marilyn McGinnis, PhD, a professor at Mount Sinai School of Medicine. Those potential differences do not explain the results of Pope's study, in which all of the participants received the same steroid, but they could account for the more extreme variations seen in real-world users, who often "stack" multiple drugs to increase muscle mass.
Teen-age steroid use
Steroids can have adverse psychological and physical consequences at any age, but they may be especially damaging during the teen-age years, when hormone levels are in flux and the body and brain are developing rapidly.
Since 1996, Melloni's laboratory has been studying the effects of anabolic steroids on the development of aggression-related brain circuits under a grant from National Institute on Drug Abuse (NIDA). His work has shown that high doses of AASs can change the way the hypothalamus develops in adolescent hamsters, decreasing the amount of available serotonin, which inhibits aggression, and increasing the amount of vasopressin, which increases aggression--essentially letting up on the brake while pressing on the gas.
"One of the things that is really at the crux of the issue here is that kids are using these things at very high doses," he says. "That population is at great risk for aggressive outbursts because they're stimulating--grossly overstimulating--steroid signaling pathways during a time when aggression circuits in the brain are at their most vulnerable."
For obvious reasons, research on the effects of steroids on human adolescents is rare, but many researchers are concerned about the implications of the animal research. McGinnis wonders, "What are you doing by exposing your adolescent brain to buckets of testosterone? Are you permanently altering some wiring that can never be reversed?" Studies in her lab have shown that most steroid effects wear off after about 16 weeks in adult rats, but without further research, it is impossible to tell whether the same would be true of adolescent rats, let alone human teen-agers, she says.
While McGinnis primarily has studied the effect of AASs on male animals, Dartmouth College psychologist Ann Clark, PhD, has focused on females. "What we've seen so far in females [is] that what anabolic steroids do to puberty depends both on what steroid you're injecting and what dose you're injecting," she says. Her research has shown that some effects of steroids, such as the suppression of female sexual receptivity, wear off soon after steroid use is discontinued. But for other effects the relevant research simply has not yet been done.
That concerns researchers such as Linn Goldberg, MD, head of the Division of Health Promotion and Sports Medicine at Oregon Health and Science University, who are trying, with some success, to reduce rates of steroid use among teen-agers. "When you give [steroids] to an adolescent that's developing, you're messing around with hormones and Mother Nature," he worries. "You are changing the course of development."
Advertising and ATLAS
If the short-term risks are so clear and the long-term risks still unknown, why do so many continue to use steroids? Pope believes that changing conceptions about the male body are partly to blame. Today's media is saturated with images of male physiques that cannot be achieved without the help of steroids, he says. His research has shown that "Mr. America" winners from the pre-steroid era of the 1930s and 1940s look like lightweights next to today's average steroid-enhanced bodybuilder, and that GI Joe and other action figures have grown over the past 30 years into muscular supermen--"more male than male"--whose biceps are sometimes wider than their waists.
As a result of these and other media images, says Pope, men are increasingly obsessed about their bodies, a phenomenon that he and his co-authors dubbed "The Adonis Complex" in a 2000 book by the same name. In some individuals, the obsession with physique can reach pathological levels. "Muscle dysmorphia," as it is called, is a subclass of body dysmorphic disorder in which individuals perceive themselves as embarrassingly scrawny, even if bodybuilding and steroid use have made them more muscular than average.
Goldberg agrees that the changing male body image has contributed to recent increases in steroid use, but he also thinks that the media have played a more direct role in promoting steroids. He notes that the term "on steroids" has been used so often in advertisements--to describe bigger and better versions of everything from stick-on notes to luggage racks--that it has lost many of its negative connotations.
The world of elite sports has also contributed to the problem, Goldberg suggests. "You've got a whole atmosphere, a culture of cheating, so that filters down to kids," he says. Sports magazines tend to emphasize the muscle-building powers of steroids even in articles that purport to describe their dangers. Widespread cheating in the Olympic sports world and steroid use by professional athletes have helped create the misimpression that "natural" athletes who play by the rules can't get to the top, he says.
Melloni agrees. "Kids emulate their heroes in baseball," he says, which is why each new revelation of steroid use among elite athletes has the potential to boost abuse among the most vulnerable age group. "The earlier kids start using these things, the longer they're going to use and the more they're going to use," he adds.
Not all teen-agers succumb to the media blitz, however, and of those who do only a fraction are willing to accept the stigma associated with steroids, many of which can be administered only via injection. The "Monitoring the Future" study, conducted by the University of Michigan Institute for Social Research with funding from NIDA, surveys drug use among high-school students each year. For 2001, the survey indicates that only 2.4 percent of seniors had used steroids in the previous year--more than had used heroin, but significantly fewer than had used other illicit drugs like cocaine and ecstasy.
The 2.4 percent figure is deceptively low, though, because it combines prevalence rates for males and females. In 2001, the number of senior males who had ever used steroids was almost four times larger than the comparable number of females. According to demographic studies, male steroid users are more likely than nonusers to be involved with athletics, use other illicit drugs, suffer from body-image problems and antisocial personality disorder, and be sensation-seekers. Female users also tend to be athletes, but they are less likely to be sensation-seekers and more likely to have body image-related disorders like anorexia or bulimia.
Goldberg's ATLAS program--Athletes Training and Learning to Avoid Steroids--attempts to reduce steroid use by teaching teen-age males about healthy diet and athletic training techniques. It is one of the few in-school drug education programs that reliably succeeds in reducing steroid use among teens, sometimes by as much as 50 percent. The program began in Oregon and Washington in 1993 and has since spread to school districts throughout the country.
Goldberg and his colleagues have also developed a program called ATHENA--Athletes Targeting Healthy Exercise and Nutrition Alternatives--which is similar to ATLAS but focuses on teen-age girls, who, though few in absolute number, are the fastest-growing demographic group for steroid abuse. The program emphasizes positive body image, healthy diet and exercise. It also explains the specific risks of AASs for females, such as deepening of voice, growth of unwanted body hair and suppression of menstruation.
Goldberg stresses that further research on the long-term effects of steroids is important, but programs like ATLAS and ATHENA are the first line of defense. "Our primary purpose in doing our research is trying to prevent kids from going on these drugs in the first place," he says.