If you have ever tossed and turned under heavy blankets, you’ve felt firsthand how being too warm can wreck your sleep.
“Temperature is one of the most underappreciated factors in sleep,” said Joseph Dzierzewski, senior vice president of research and scientific affairs at the National Sleep Foundation. “We often hear about light, screens and stress, but even modest changes in temperature and airflow can influence how quickly you fall asleep and how deeply you stay asleep.”
Your core body temperature naturally drops by about 1 to 2 degrees Fahrenheit (about 0.6 to 1 degree Celsius) to fall asleep, he said, and if that cooling process is disrupted even slightly, sleep can become more fragmented and less restorative.
The most important thing is creating what Dzierzewski calls a comfortable sleep microclimate, in which your body isn’t trapping heat between your skin, sleepwear and bedding.
“For some people, that may mean sleeping naked or with minimal clothing; for others, lightweight, moisture-wicking fabrics work well,” he said. The goal is to feel comfortable and secure while helping your body cool naturally.
For Brian Diva Cox in Portland, Oregon, that microclimate is easiest to achieve without pajamas. He said sleeping naked became a nightly habit in his teens and, while it’s more occasional now as an adult, he still does it when he wants to prioritize comfort and recovery — especially on nights when time is short.
“I wake up refreshed,” he said, adding that he invariably has energy and his smart watch’s sleep chart shows his improved sleep quality the next day.
Whether you ditch your pajamas or simply switch to lighter layers, reducing insulation can make it easier for your body to release heat. Interestingly, Dzierzewski also noted that warming the hands and feet before bed can help the body release heat more efficiently and fall asleep faster. For people who naturally have cold extremities, keeping them comfortably warm during sleep can also help maintain more stable sleep.
How much moisture there is in the air matters, too.
“High humidity limits your body’s ability to cool itself through sweat,” he said, so using breathable, moisture-wicking materials in mattresses, bedding and sleepwear can all help your body offload the heat.
Keeping a cooler room, typically around 60 to 67 degrees Fahrenheit (around 15 to 19 degrees Celsius) with good airflow, can also support that process, Dzierzewski explained. Be flexible with those temperatures, since comfort can vary by person and people who sleep hot or are experiencing hormonal changes tend to prefer the cooler end of the range.
Finally, it’s not just about setting a cooler temperature — it’s about keeping it consistent through the night. Big swings can trigger middle-of-the-night wake-ups if you start overheating.
Temperature doesn’t just affect sleep quality — it plays a role in reproductive health, too.
“The testes are outside the body for a reason — optimal sperm production requires temperatures a few degrees below core body temp,” said CNN contributor Dr. Jamin Brahmbhatt, a urologist and robotic surgeon with Orlando Health. That’s why what you choose to wear or not wear to bed can matter.
Brahmbhatt, who is also an assistant professor at the University of Central Florida’s College of Medicine, also referenced a large Harvard University study that showed men who wore boxers had higher sperm concentration than those who wore formfitting styles. But he said the key factor is not the tightness itself, but the heat.
“Tight underwear traps heat against the body,” he explained, echoing the same reasoning around warnings about hot tubs and laptops — the excessive heat. “It’s less about compression and more about the level of insulation,” he said.
The takeaway? Sleeping cooler — whether naked or in breathable clothing — may help reduce heat buildup overnight. Better sleep itself may also support hormone health.
“When men sleep better, testosterone production improves,” he added. Because testosterone is primarily produced during sleep, deeper, more restorative rest can support energy, mood and sexual function. Better sleep leads to a better hormonal balance, which supports libido, he said.
“You don’t have to sleep naked to get these benefits. You just have to sleep cool,” he added. If you do choose to skip the clothes, he advised that it’s important to wash your sheets more frequently.
Sleeping naked or in minimal clothing with your partner may have perks beyond temperature control.
For some couples, cuddling skin-to-skin becomes a “way of feeling connected and close,” said CNN contributor Ian Kerner, a licensed marriage and family therapist. It doesn’t have to be sexual, he added, but it can help keep a sense of connection alive — and it sometimes creates more opportunity for sex when couples arrive in bed exhausted.
Even when it doesn’t lead to sex, the contact itself can be meaningful. Skin-to-skin touch is associated with oxytocin, a hormone linked to bonding and emotional closeness, he said.
“This is a nice way of showing up in bed without having sexual desire — but potentially getting to desire,” Kerner said. “The couples that I work with who sleep naked, they like it. It becomes a ritual.”
Having the conversation with your partner before you go “no PJs” is critical, and Kerner shared some tips on how to broach the topic. One approach you could take is light and fun, saying “I am going to be sleeping naked tonight. Care to join me?” he said, emphasizing that this doesn’t have to be a sexual thing. Another way is expressing to your partner that you miss intimacy or feeling close and offering getting in bed naked as an option to feel more connected, he said.
For couples trying to reconnect, he sometimes suggests what he calls a “willingness window” — a low-pressure way to prioritize closeness. Partners do not need to show up with desire, just willingness. “Sleeping side by side naked could be a first step,” he said. “You don’t have to make it a habit — even once a week, just to see how it feels.”
While Kerner doesn’t see sleeping naked as a requirement, it could be used as an excuse to get in bed and be naked and without our phones and be human with each other for a little while, he said.
Whether you are ditching pajamas entirely or just switching to lighter fabrics, the goal is the same — helping your body cool down, sleep more deeply and, potentially, feel a little more connected in the process. If you do choose to sleep naked, make sure to keep clothes handy in case of emergencies.
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