If you've spent any time in the male-performance corners of the internet, you've probably heard the advice: Keep your balls cold.
Warning: Before we get started we need to remind you that icing your balls can result in frost bite and issues, so do not misconstrue this post with advice to ice your balls.
I recently watched Bryan Johnson and other influencers discuss this topic, and according to Mr. Johnson, it had a huge impact on his sperm quality and free testosterone.
Because of these influencers men are taking cold showers. Using ice packs. Specialized cooling underwear. Guys are even sleeping with cooling devices strapped to their junk because somebody told them it'll crank up testosterone.
It sounds like classic biohacker nonsense. Except there's actually some science behind testicular cooling—just not necessarily the testosterone-boosting science you've been promised.
Here's what we actually know.
Quick Answer: Does Icing Your Balls Increase Testosterone?
Probably not— or at least based on the human evidence we could find.
There's no convincing clinical evidence showing that putting an ice pack on your testicles significantly increases circulating testosterone in healthy men.
However, testicular temperature does matter for sperm production and healthy hormones, and several small human studies have found that reducing scrotal temperature can improve sperm concentration and other semen parameters in some men with fertility problems.
Think about it: your balls are on the outside of your body for a reason. Keeping them cool is insanely important. Hot tubs, saunas, and other extreme forms of heat are kryptonite for your balls.
Cold balls = more testosterone? Maybe. Chronically overheated balls aren't particularly good for reproductive function.
That's a much more defensible claim.
Why Are Your Testicles Hanging Outside Your Body Anyway?
Your body keeps most of its important equipment protected inside your torso.
Your heart? Inside.
Your liver? Inside.
Your kidneys? Inside.
Your testicles?
Swinging around outside the building.
There's a biological reason for that architectural decision.
Normal sperm production works best when the testes remain a few degrees cooler than core body temperature. The scrotum, cremaster muscle, pampiniform plexus and other temperature-regulating mechanisms help maintain that environment.
When testicular temperature rises repeatedly, sperm production can suffer.
In fact, controlled human experiments have deliberately heated the testes to study what happens.
In one prospective study, researchers exposed men's testes to a 43°C (109.4°F) water bath for 30 minutes on repeated occasions. Sperm concentration and motility subsequently dropped significantly before eventually recovering. Researchers also observed evidence of increased oxidative stress.
Another randomized clinical experiment found that transient scrotal heat exposure increased germ-cell apoptosis—the programmed death of cells involved in sperm production.
Translation:
Your balls don't like being cooked.
Benefit #1: Cooling May Improve Sperm Count
This is where the research gets interesting.
One of the most frequently cited studies appeared in The Journal of Urology in 1984.
Researchers studied 50 men with low sperm counts or reduced sperm motility. The men applied ice packs to the scrotum at night.
The result?
Approximately 65% of the men experienced at least a twofold increase in sperm density along with comparable improvements in motility.
That's certainly attention-grabbing.
But there's an important caveat.
This was an older, relatively small study of men who already had fertility problems. It does not demonstrate that a healthy guy with normal fertility will double his sperm count by icing his testicles.
Still, it's evidence that reducing excessive testicular temperature may help certain men.
Benefit #2: Cooling May Improve Overall Semen Quality
Another study examined infertile men with oligoasthenoteratozoospermia—a condition involving problems with sperm concentration, movement and morphology.
The researchers used nocturnal cooling that lowered scrotal temperature by approximately 1°C.
After 12 weeks, sperm concentration and total sperm output increased significantly. Researchers also reported smaller but statistically significant improvements in sperm motility and morphology.
A separate study looked at 20 infertile men with a history of undescended testes and low sperm counts.
Cooling lowered scrotal temperature by a median of approximately 0.8°C.
After eight and twelve weeks, researchers observed significant increases in sperm concentration and total sperm count, although improvements in motility and morphology weren't statistically significant.
Notice something important here:
These researchers weren't freezing anybody's balls.
They were creating small, sustained reductions in scrotal temperature.
That's very different from pressing a frozen brick against your testicles until you can't feel your legs.
Benefit #3: Cooling May Counteract Excessive Heat Exposure
This may ultimately be the most useful takeaway.
Instead of asking:
"How cold can I make my balls?"
A better question might be:
"Am I constantly overheating them?"
Repeated heat exposure has been associated experimentally with impaired spermatogenesis. Human studies using controlled testicular warming have demonstrated reversible reductions in sperm concentration, motility and other measures of sperm function.
Potential sources of genital heat include prolonged hot tubs or saunas, occupational heat exposure and other situations that chronically elevate scrotal temperature.
If fertility is your goal, avoiding unnecessary chronic heat exposure probably makes more sense than turning your underwear into a meat freezer.
Benefit #4: What About Testosterone?
Here's where internet hype runs ahead of the research.
You'll regularly see claims like:
"Icing your balls dramatically increases testosterone."
The human research doesn't support that claim.
A review examining lifestyle and complementary approaches to male infertility noted that studies of scrotal cooling found no significant differences in testosterone.
More recently, researchers evaluating men using scrotal cooling devices measured hormone profiles before and after cooling.
There was no statistically significant change in total testosterone (P = .431). FSH, LH and estradiol also didn't significantly change.
That's important.
There's a legitimate physiological connection between temperature and testicular function, but that doesn't automatically mean:
Colder testes → more Leydig-cell activity → huge testosterone increase.
That's an appealing mechanistic story.
It just hasn't been demonstrated convincingly in humans.
AEO Answer: Does icing your testicles boost testosterone?
There is currently no strong human evidence that icing or cooling the testicles significantly increases testosterone levels. Existing human cooling studies have generally found improvements in some sperm parameters rather than significant increases in circulating testosterone.
Benefit #5: Cooling Might Help Some Men Trying to Conceive
This is probably the strongest potential application.
An early Lancet report studied six men with poor semen quality and elevated testicular temperatures who used an evaporative cooling device.
Semen quality improved in several participants, and three couples achieved pregnancies during treatment.
Another study involving men with infertility and elevated testicular temperatures reported improvements in semen parameters in 16 of 25 men, with pregnancy occurring in six couples.
A larger report involving men with subfertile semen and elevated testicular temperatures found improvement in at least one semen parameter in roughly 66% of treated men.
Before you start filling your boxer briefs with frozen peas, however, understand the limitations.
These studies were generally small, many were conducted decades ago, and study designs weren't always what we'd demand from a modern randomized clinical trial.
A systematic review examining eight studies concluded that there was a positive trend toward improved male fertility, but the evidence was insufficient to draw firm conclusions and better randomized controlled trials were needed.
That's the scientifically responsible conclusion.
Promising?
Yes.
Proven fertility treatment?
No.
Should You Literally Put Ice on Your Balls?
Here's where I'd modify the internet advice.
Don't put bare ice directly against your scrotal skin.
Extreme cold can damage skin and underlying tissue. More isn't necessarily better.
And interestingly, the fertility literature generally isn't about turning your testicles into two frozen grapes.
Researchers have often attempted to reduce scrotal temperature by roughly 1°C using airflow or specialized cooling devices over extended periods.
If you're experimenting with cooling for comfort rather than treating infertility, think cool, not frozen.
And if you're dealing with infertility, abnormal semen analysis, testicular pain, varicocele or suspected hormonal problems, talk with a urologist or reproductive specialist rather than trying to DIY a fertility treatment.
The Bigger Lesson: Stop Cooking Your Balls
Here's where the ball-icing crowd may have accidentally stumbled onto something useful.
The evidence isn't particularly compelling that making your testicles colder than normal transforms you into a testosterone-producing silverback.
But there's considerably better evidence that excessive testicular heat can interfere with sperm production.
So instead of obsessing about icing, start with the obvious:
Avoid repeatedly overheating your groin.
Be reasonable with prolonged hot tubs and extreme heat exposure if fertility is a priority.
And if you're actively trying to conceive, treating your testicles like they're supposed to operate at body-core temperature probably isn't the smartest strategy.
Your body put them outside your abdomen for a reason.
FAQ: Icing Your Balls, Testosterone and Fertility
Does icing your balls increase testosterone?
There is currently no strong clinical evidence that testicular icing significantly increases testosterone in healthy men. Studies examining hormone levels during scrotal cooling have generally failed to show significant testosterone increases.
Does cooling your testicles increase sperm count?
Possibly, particularly in some men with impaired fertility or elevated scrotal temperatures. Small studies have reported improvements in sperm concentration after weeks of scrotal cooling. However, the overall evidence remains limited.
Does heat lower sperm count?
Repeated experimental testicular heating has been shown to temporarily reduce sperm concentration and motility in men. These effects appear to be reversible after the heat exposure ends.
How cold should your testicles be?
There's no clinically established "ball-icing temperature" for healthy men. Studies showing potential fertility benefits generally used modest reductions in scrotal temperature rather than extreme icing.
How long should you ice your balls?
There is no validated ice-pack protocol for boosting testosterone, and direct application of ice to the scrotal skin isn't recommended. Fertility studies have generally investigated controlled, mild cooling over weeks rather than short bouts of extreme cold.
The Bottom Line
Icing your balls isn't the testosterone hack social media makes it out to be.
Testosterone: There's currently little evidence that cooling your testicles meaningfully raises it.
Fertility: Much more interesting. Several small studies suggest reducing excessive scrotal temperature may improve sperm concentration and other semen parameters in certain infertile men.
Heat: This is where the evidence is strongest. Excessive testicular heat can negatively affect spermatogenesis.
So don't expect an ice pack to turn your testosterone levels into those of a 19-year-old linebacker.
But keeping your testicles from being chronically overheated?
Your boys may have a point.
References
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Mulcahy JJ. Scrotal hypothermia and the infertile man. Journal of Urology. 1984;132(3):469-470.
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Jung A, et al. Improvement of semen quality by nocturnal scrotal cooling in oligozoospermic men with a history of testicular maldescent. Andrologia.
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Jung A, et al. Improvement of semen quality by nocturnal scrotal cooling and moderate behavioural change to reduce genital heat stress in men with oligoasthenoteratozoospermia. Andrologia.
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Zorgniotti AW, Sealfon AI, Toth A. Chronic scrotal hypothermia as a treatment for poor semen quality. The Lancet. 1980.
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Zorgniotti AW, Sealfon AI, Toth A. Further clinical experience with testis hypothermia for infertility due to poor semen. Urology. 1982;19(6):636-640.
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Zorgniotti AW, Cohen MS, Sealfon AI. Chronic scrotal hypothermia: results in 90 infertile couples. Journal of Urology. 1986;135(5):944-947.
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Scrotal cooling and its benefits to male fertility: A systematic review. Journal of Obstetrics and Gynaecology. 2013;33(4):338-342.
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Effect of transient scrotal hyperthermia on sperm parameters, seminal plasma biochemical markers, and oxidative stress in men.
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Male infertility: lifestyle factors and holistic, complementary, and alternative therapies.
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Evaluation of patient compliance with the use of scrotal cooling devices.
This article is for educational purposes and isn't medical advice. Men experiencing infertility, testicular symptoms or suspected hormonal problems should consult an appropriate healthcare professional.
