Leonard Sax is the author of “Boys Adrift: The Six Factors Driving the Growing Epidemic of Unmotivated Boys and Underachieving Young Men.”
In July, Defense Secretary Pete Hegseth announced a mandatory program to test all service members 30 and older for low testosterone and to offer voluntary testosterone replacement therapy to those who test low. The mandate appears to include women. Hegseth has put forth some out-there beliefs, such as when he has promoted a church leader who has advocated the abolition of women’s right to vote. Is this another one of those weird ideas?
Not necessarily. Men rely on testosterone for drive and motivation, for the will to win. When testosterone levels fall, men’s motivation falls — though the same is not true for women.
And testosterone levels in men are in fact dropping. Between 1999 and 2016, the average testosterone level among young men fell by 25 percent. In 1999, only 4 percent of men had low testosterone. In 2016, more than 20 percent of men did — a fivefold increase in less than 20 years. These findings were confirmed in a more recent review, which found no taper in that trend line: Not only are testosterone levels continuing to drop among men, but the pace of the decline appears to be accelerating.
For decades, investigators have been trying to understand the causes of the decline. Obesity at first seemed a likely culprit. Men have been getting fatter, and fat men have lower testosterone levels than slender men because fat cells contain aromatase, an enzyme that converts testosterone to estrogen.
But the story is not so simple. Endocrine disruptors — man-made chemicals that mimic the action of female hormones — themselves lead to obesity. Endocrine disruptors also directly lower testosterone. The emerging consensus among leading investigators in this field is that the driving cause of reduced testosterone is the endocrine disruptors in foods, beverages and cosmetics. These substances lower testosterone levels directly and indirectly, by leading to obesity.
But scientists have also documented compelling evidence that women do not rely on testosterone for drive or motivation. Because women’s testosterone levels are normally about one-tenth the normal level for men, screening female service members for “low testosterone” makes no sense. For women, testosterone treatment — which is voluntary for service members under the program — would cause facial hair, voice changes and other masculinizing features that most women are not likely to welcome.
Hegseth’s order overlooks data in other ways, too. Though men under 30 are exempt from Hegseth’s order, in the most recent review, the decline in testosterone levels was larger among men 18 to 30 years of age than among men 31 to 40 years of age. And testosterone replacement therapy has been linked to male infertility, a problem the defense secretary did not acknowledge.
Military service itself can also lower testosterone levels. Combat, as well as training for combat, involves exposure to concussive blasts. Such exposure has been shown to cause traumatic brain injury, which in turn leads to lower testosterone levels. According to some estimates, 85 percent of Special Forces troops experience traumatic brain injury from training alone. A better program might have endorsed research to better understand these risks.
Still, Hegseth was right about one thing: Testosterone matters for men. The program would be more helpful if it had taken into account the consensus among researchers regarding the primary cause of this decline: namely, exposure to endocrine disruptors. In a peer-reviewed study published by the National Institutes of Health, I reviewed evidence showing that clear plastic bottles — the same ones used for bottled water, soda, ketchup, mustard and more — leach endocrine-disrupting substances such as diethyl hexyl phthalate and antimony into the contents of the bottle. Diethyl hexyl phthalate can act in the body like an estrogen, lowering testosterone levels in men, and antimony is also a known endocrine disruptor. Other studies, citing my work, have confirmed and extended my findings.
The good news is that most men do not need testosterone shots. Simple, zero-cost strategies to avoid exposure to endocrine disruptors are the first line of intervention. Here are some evidence-based guidelines.
Do not microwave food in plastic containers or plastic packaging. Many frozen foods now come in “boil in the bag” packaging. Take the food out of the plastic and put it in a glass or ceramic bowl instead.
When heating a meal in the microwave, do not allow a plastic cover to contact the food. Use a dish instead. If you must use a plastic cover or wrap, then put the food in a bowl rather than a plate so that the plastic wrap does not come into contact with the food.
Avoid plastic bottles for beverages, including water. If you want to carry water with you, pour tap water into a steel canteen. It is cheaper than bottled water, better for the environment and better for you.
The U.S. Army has revived the slogan “Be All You Can Be” for its recruitment. I am all for being all you can be. I hope that to help service members do so, Hegseth and other military leaders will turn to scientists and their research, so that the testosterone screening program will be helpful rather than hurtful.
The post Low testosterone is a real problem, but don’t forget this major cause appeared first on Washington Post.
