SOLID ENERGY LEVELS, good grip strength, clear skin, breath that’s inoffensive—these are just a few of the top signs you’re in good health. But we’re here to add one key indicator to the list: morning wood. Whether you know it or not, experts agree that waking up with a boner is actually one of the best ways to tell your downstairs plumbing is working properly.
While it may not be the most convenient thing in the world—particularly when you have to pee—morning wood, also known as nocturnal penile tumescence, is also super common. According to Seth Cohen, M.D., a board-certified urologist and Ro advisor, men tend to experience an erection around every 90 minutes during their sleep cycle—so it’s not all that surprising that you might rise out of bed with a full rager. It can tell you a lot, too—and not just about your sexual health.
“It means that your heart is healthy, your blood pressure is in check, and your hormones are balanced,” he explains.
A 2022 study found that men who get morning wood are 22 percent less likely to die from heart disease or stroke. Researchers attributed this link to the fact that night-time erections indicate good circulation.
All of this might help to explain why at one point, urologists diagnosed erectile problems by asking cisgender men to place a roll of stamps over their penises before going to sleep. If the roll had been broken by the morning, that meant a man was purportedly getting overnight erections. (FYI, the stamp test is no longer used by urologists. Now there’s a portable home device you can purchase, called a RigiScan, which analyzes your nocturnal penile erections.)
As reassuring as all that might be, we know you may still have some questions about those hard-ons you wake up with. So, to learn more about the ins and outs of morning wood, we spoke to a few experts—including Cohen and the following:
- Adam Ramin, M.D., urologist and medical director of Urology Cancer Specialists in Los Angeles, California
- Tobias Köherl, M.D., M.P.H., urologist at the Mayo Clinic
- David Shusterman, M.D., a board-certified urologist and founder of NY Urology
- Andrew Y. Sun, M.D., a board-certified urologist and advisor to Marius Pharmaceuticals
Here’s what they had to say.
What causes morning wood?
Contrary to what you might assume, experts say morning wood is not necessarily a sign that you were having an X-rated dream. It’s a little more complicated (and less sexy) than that.
Erections are caused by the stimulation of the parasympathetic nervous system. When you see, feel, hear—and maybe even smell or taste—something that is sexually attractive, it triggers the release of neurotransmitters. This leads to the dilation of arteries in the penis, which means more blood flows into the penis, which in turn causes the penis to become erect. The parasympathetic system is more active when you’re sleeping, which in addition to producing erections, also causes your muscles to relax and your heart rate to slow.
According to Cohen, morning wood may also be caused by the nitric oxide that’s produced during the rapid eye movement (REM) cycle of sleep.
“It’s believed that nitric oxide can make the blood vessels in the penis relax,” he tells Men’s Health. “This can cause blood to enter the penis, causing an erection.”
During REM sleep, there’s often increased circulation to the penis—along with hormonal spikes that can trigger nocturnal erections—says Sun.
According to Shusterman, testosterone—which often peaks in the early morning—can also contribute to morning wood.
Is morning wood healthy?
According to Ramin, a healthy cis man should expect to get hard three to five times per night. If this isn’t happening, it could be a sign of underlying health issues like nerve malfunction, arterial disease, hypertension, diabetes, or low testosterone.
Morning wood is also a sign that the pesky erectile dysfunction you may be experiencing is psychological, not physiological. If you can’t get it up in the bedroom but find yourself waking up with morning wood, you may want to see a therapist. (However, depression and anxiety can actually lead to parasympathetic nerve malfunction, affecting both your daytime and nighttime boners.) If you’re not getting erections at night or when you’re about to have sex, it could be a sign of some of the aforementioned health conditions.
So yes, morning wood is healthy.
“Think of morning wood as your body’s ‘check-engine light,’” says Sun.
In other words, if you’re not hard when you wake up, it’s time to look under the hood.
What purpose does morning wood serve?
“There is no true purpose to the development of nocturnal erections,” says Ramin. “They are merely a byproduct of a natural stimulation of the parasympathetic nervous system at night.”
Though morning wood serves no specific function, it might be the best indication that your penis is functioning properly. The erection reps you’re getting at night also act as a kind of unconscious exercise regimen for your penis, helping keep its tissue soft, stretchy, and ready to go whenever your social agenda requires a little increased blood flow.
According to Köhler, the absence of morning wood could even cause the muscles in your penis to become too contracted, which over time could cause the length of your penis to shorten.
How do I prevent morning wood?
If you’re getting morning wood, it’s a good thing! It means you have a healthy penis. Nevertheless, a lot of people have this question, because let’s face it: It can be awkward to wake up next to someone—especially someone you don’t know super well—and have to hide your raging erection.
The real question you should be asking is: How do I make my erection go away? Distracting yourself, taking a cold shower, and meditating can all help, according to Healthline. For more tips, we asked people for tips on how to stop being horny, fast, and here’s what they had to say.
What should I do if I’m not getting morning wood?
According to Ramin, if you’re not waking up with morning wood at least occasionally, you may need to go see a doctor. It’s possible you’re still getting erections during the night without being aware of it, but if a month or two goes by without anything happening in the AM, it could be time to get checked out. Schusterman notes that getting to the bottom of the root problem may involve bloodwork to test your testosterone levels, diabetes screening, conducting an ultrasound, and checking your blood pressure.
Treating the underlying issues–with, say, statins to clear out cholesterol-clogged veins, or testosterone replacement therapy if your levels are low–can improve your erections and your overall health, says Köhler.
How can I make sure I’m getting enough morning wood?
If you’re worried about your morning wood, it doesn’t hurt to keep tabs on how often you’re waking up with an erection. As is the case with just about everything these days, there’s an app for that. Morning Glory was designed by men’s health and wellness startup Roman to help guys track their erections. Just open up the app, record when you do and do not wake up with morning wood, and the app will tell you when you may need to go see a physician.
“We hope that this app will help guys form the habit of paying more attention to their bodies and talking to a doctor at the earliest sign that something could be wrong,” a company representative told Men’s Health.
Yes, the app is pretty gimmicky, but it underscores the importance of morning wood. “It’s very important for a man to understand the basis for their erection,” Roman’s medical advisor, NYU’s Dr. Steven Lamm, says in a video promoting the app. “When a man is having erections they’re generally in very good health. When they’re not having erections, it’s time to visit your doctor.”
There’s also the RigiScan, in case you’re not an app guy.
