More testosterone is a good thing, right? Conventional wisdom touts the male sex hormone as beneficial when it comes to reproductive fitness, building muscle, increasing metabolism and decreasing fat tissue — not to mention boosting sex drive, energy and mood. But according to one scientist, all those benefits come at a high cost: your life.
It’s no secret that men have shorter overall lifespans than women: The average in the U.S. is 76.4 years for men and 81.2 years for women. But high testosterone levels play a role in that number, leading to a shorter lifespan and poorer general health, according to Richard G. Bribiescas, professor of anthropology and ecology and evolutionary biology at Yale. In a feature for science magazine Nautilus he explains the numerous ways that high testosterone can contribute to death.
Suppressed Immune Function
Suppressed immune function makes it harder for men to fight off infections. Bribiescas writes, “In the words of Yale evolutionary biologist Stephen Stearns, ‘Macho makes you sick.’ Meanwhile, estradiol, the primary sex steroid in women, bolsters immune function.”
Increased Risk of Cancer
“Populations with higher testosterone levels tend to also exhibit higher incidence of prostate cancer,” reports Bribiescas. It makes sense, then, that lowering testosterone levels using drugs is a common treatment for prostate cancer. Meanwhile, if your testosterone is too low, this can actually also increase your chances of developing prostate cancer.
Promotes Risky Behavior
Men are more violent and consistently consume more tobacco, alcohol and drugs than women, according to a paper from the Society of Actuaries entitled “Why Men Die Younger.” This combination of risky behavior and substance abuse — a risky behavior in itself — makes men on average more prone to death at an earlier age.
But men need testosterone to promote muscle growth and increase metabolism. Men allocate a ton of energy to improve their chances of reproduction, says Bribiescas. “This ‘reproductive effort’ takes place through engagement in riskier behavior and the accumulation of greater body mass, particularly sexually dimorphic skeletal muscle mass, the extra male-specific muscle in the shoulders, back and arms.”
But building muscle isn’t cheap. “The metabolic costs of maintaining this muscle in men over a lifetime are comparable to the energy expenditure women experience during pregnancy and breast-feeding,” he says.
So what’s a guy to do if he wants to increase his chances of reproductive success while also avoiding dying young? Bribiescas says it’s simple: Become a father and invest in your child’s upbringing.
He explains, “Men evolved an alternative form of reproductive effort in the form of paternal investment — something very rare in primates (and mammals in general). For paternal investment to evolve, males have to make sure they are around to take care of their offspring. Risky behavior and expensive tissue [or muscle building] have to take a backseat to [an] investment that reflects better health and perhaps prolongs lifespan.”
Indeed, when men enter fatherhood and start caring for their children, their testosterone levels decline, says Bribiescas. “Perhaps, then, fatherhood is good for health.”
And if a longer life is your goal for fatherhood, fingers crossed you have a girl. Daughters may very well increase longevity in fathers, according to a 2006 study of mothers and fathers in Poland.
Erin has made telling stories about food her profession. You can find those stories in Food & Wine, LA Weekly, Serious Eats, KCET, Robb Report and First We Feast.
What Do YOU Think?
Should men be careful about taking testosterone-enhancing supplements? Should society put less pressure on men to be “macho,” considering testosterone can make you sick?