Reviewed by Denise Asafu-Adjei, M.D., MPH
A few years back, PN co-founder John Berardi, PhD, posted a shirtless photo of himself on his 47th birthday.
He called it his “anti-regress pic” and thanked 30 years of squats, deadlifts, presses, and chin-ups—among other exercises—for his chiseled six-pack, pumped chest, and bulging biceps.
The question many commenters posed:
“Are you on testosterone?”
Dr. Berardi explained in a follow-up post that while he wasn’t against testosterone replacement therapy (TRT) for people who needed it, he himself was not on this therapy, and his testosterone levels were boringly “normal.” He also offered some thought-provoking ideas about testosterone and aging.Dr. Berardi’s take is the opposite of what you generally hear, especially these days when…
- The mainstream opinion seems to be that declining testosterone is a harbinger of aging, frailty, and impotence—not to mention a threat to masculinity.
- Increasing numbers of middle-aged men are ditching traditional medical checkups for men’s-focused telehealth clinics that specialize in testosterone enhancement.1
- Reddit communities have popped up solely to obsess over neuroscientist Andrew Huberman’s supplement recommendations for optimizing testosterone.
- Media outlets pump out story after story about “testosterone boosting” foods to eat and “testosterone lowering” foods to avoid.
Whether you’re a coach who fields the “How do I optimize testosterone?” question from clients—or just a regular dude hoping to age well—it’s easy to feel overwhelmed and confused by the conflicting information.
Are declining testosterone levels normal?
Do testosterone-boosting supplement regimens actually work?
Who benefits from testosterone therapy—and who doesn’t?
In this story, we’ll explore those questions and more.
What is testosterone?
Secreted by the testes, testosterone is the sex hormone responsible for male sexual characteristics such as big muscles, deep voices, and hairy chests. It’s a chemical messenger that plays a key role in various processes throughout the body, including sperm production and bone density.
(In women, who also need testosterone to keep various processes humming, testosterone is secreted by the ovaries and adrenal glands. Their bodies just make much less of it; about 10 to 20 times less than men.)
Possibly because of its relationship with muscle growth and sex drive, a lot of cisgender men think of testosterone in binary terms, with lower testosterone being bad and higher testosterone being good.
However, it’s more accurate to think of the relationship between testosterone and health as a continuum that goes from too low (problematic) to too high (also problematic), with the healthy range falling between the two extremes, says Denise Asafu-Adjei, MD, MPH, urologist, men’s health expert, and assistant professor of urology at Loyola University Chicago-Stritch School of Medicine.
As the chart below shows, the dangers of extremely low testosterone are similar to the risks of extremely high amounts (typically only achievable with the use of anabolic steroids).
| Problems associated with extremely LOW testosterone | Problems associated with extremely HIGH testosterone |
|---|---|
|
|
Low testosterone vs. lower testosterone
Testosterone levels naturally ebb with age, with most men losing about 1 to 2 percent annually starting around age 40. By age 75, most men have 30 percent less of the hormone than they did at age 25.2
(Fun fact: Between ages 25 and 80, men can expect their testicles to shrink 15 percent.3)
However, age-related drops in testosterone are not the same thing as “low testosterone.”
Hypogonadism is the medical term for low testosterone levels, and it affects about 35 percent of men older than 45 and 30 to 50 percent of men who have obesity or type 2 diabetes, according to the Endocrine Society, one of the professional public health organizations that sets hypogonadism treatment guidelines.
Not only can overly low testosterone make you feel fatigued and do a serious number on your sex drive, but it can also harm your bone and cardiovascular health, says Dr. Asafu-Adjei.
“You need testosterone for good bone strength,” says Dr. Asafu-Adjei. “As you get older, you’re already dealing with weaker bones, so having lowered testosterone isn’t going to help.”
Alternatively, bringing levels up to normal seems to offer cardiovascular benefits, she says. (The big caveat here is up to normal—not far above it.)
The importance of referring out
What if you or your client have most of the hallmark symptoms of hypogonadism but still have blood levels of testosterone in the normal range?
“Many men over 30 who feel down or low energy will now automatically blame their testosterone,” says Dr. Asafu-Adjei. “Their symptoms might be related to testosterone, but they also could be related to not sleeping, stress, or some other factor.”
That’s why seeing a healthcare professional specializing in men’s health and testosterone management is so important.
Such a physician can screen you or your client for dozens of other problems (like stress and poor sleep) and conditions (like diabetes, obesity, or sleep apnea) that either mimic the symptoms of hypogonadism or interfere with the production or signaling of testosterone.
In other words, supplemental testosterone is the answer for some men with symptoms of hypogonadism, but not all of them. An extensive workup is required.
“There are overlapping symptoms with low testosterone as well as a lot of nuances around hormone treatment,” says Dr. Asafu-Adjei.
“For example, outside of your total testosterone, we also look at your testosterone-to-estrogen ratio and other related hormones. That’s why it’s so important to go to someone who knows what they’re doing. They’ll take a deeper dive to figure out the root of the problem.”
So, if you specialize in coaching middle-aged and older men, get a urologist or endocrinologist in your referral network.
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Testosterone and aggression
Many people assume that, in high amounts, testosterone turns men into pushy, road-rage-fueled jerks. However, the association between the hormone and behavior is much more complex.4
As it turns out, both too much and too little testosterone can lead to irritability.
In addition, the link between testosterone and aggression depends a lot on someone’s personality, upbringing, context, social norms, and more.
For example, in one experiment, researchers asked forty young men to play a video game that involved accepting and rejecting offers from a proposer. If someone deemed the proposal too low, they could reject the offer and punish the person for making such a substandard ask. Alternatively, if they considered the offer beneficial, they could accept it as well as reward the person.5
Researchers injected some of the men with testosterone as they played the game.
As expected, players treated with the hormone were more likely to punish proposers, especially if they considered the offer unfair. However, if they perceived the offer as fair, they rewarded the proposer more generously.
The increased testosterone amplified aggression, but also generosity.
Some researchers refer to this phenomenon as “the male warrior hypothesis,” which holds that testosterone may function to help some men protect and cooperate with their “in group” (such as their family, friends, and coworkers) while simultaneously punishing anyone seen as an outsider.6
7 evidence-based ways to optimize testosterone… naturally
On the Internet, if you look for ways to boost testosterone through lifestyle, you’ll quickly become inundated with supplement recommendations and lists of T-boosting and T-harming foods.
However, research-supported ways to optimize testosterone generally center on the fundamental dietary and lifestyle measures you’ve long heard are good for you.
They include the following:
Testosterone optimizer #1: Make sure you’re eating enough.
Your body prioritizes thinking (your brain) and movement (your muscles) above sex (your reproductive organs).
Think about it this way: If there was a famine, the last thing you’d need is another mouth to feed.
So, when you chronically burn more calories than you consume, hormone levels generally drop. (This is true in both men and women.)
“A lot of men in their 20s and 30s come to me about their low testosterone levels and their low testosterone symptoms,” says Dr. Berardi. “These are mostly guys who prioritize exercise. They work out a lot and watch what they eat. In other words, they are men experiencing mid- to long-term negative energy balance.”
Dr. Berardi’s advice is often not what men expect.
If their eating and exercise routines suggest they’re in a chronic negative energy situation, he simply recommends they eat an extra healthy snack or two a day.
“In situations like this, adding a couple hundred extra calories of high-quality protein and carbohydrate often fixes everything,” he says.
Those added calories could come from a couple scoops of whey protein mixed in milk with a nut butter and banana sandwich on the side, he says.
Another favorite snack of Dr. Berardi’s: A bowl of steel-cut oats with protein powder, cacao powder, dates, raw nuts, and nut butter.
Keep in mind: Eating too much (and gaining fat) can also affect testosterone, as we’ll cover soon. Use our FREE nutrition calculator to ensure you’re consuming the right amount of calories and nutrients to support hormone production.
Testosterone optimizer #2: Prioritize sleep.
Testosterone production has its own circadian rhythm: It’s higher in the morning and lower at the end of the day.
As you sleep, levels rise again, peaking during your first segment of rapid eye movement. This may explain why various sleep disorders—including sleep apnea—are associated with testosterone deficiency.7
A handful of small studies have looked at what happens to hormone levels when men skimp on sleep.8 In one
