Why temperature plays a powerful role in sleep, and how cooling solutions can help

From gel foam to breathable fabrics, temperature-regulating toppers are helping hot sleepers stay comfortable without investing in a new mattress.

When people think about why they slept badly, they often focus on stress, a racing mind, or that extra cup of coffee too late in the day. Fewer consider that the problem may be physical until they wake up at 2 a.m., overheated with no clear explanation.

Research compiled by AARP estimates that 75% to 80% of midlife women experience hot flashes, many of them during the night, while studies show roughly 41% of adults, many in their 40s to mid-50s, regularly deal with night sweats. A Gallup survey also found that 57% of U.S. adults report being too hot while sleeping at least occasionally.

As interest in cooler, more comfortable beds grows, sleep-focused companies have joined the broader conversation around practical bedding changes for real homes, rentals, dorms, and budgets, raising a larger question about why temperature plays such a powerful role in sleep.

Below, Sleepyhead looks at how temperature affects your body’s ability to sleep and the practical cooling tweaks that can make an existing bed more comfortable.

Why Temperature Has Become a Top Sleep Concern

Hotter nights have turned temperature into one of the most stubborn obstacles standing between people and a full night of rest, especially as bedrooms hold heat in ways many sleepers cannot easily control.

Warmer climates, dense urban areas, and heat-retaining materials such as memory foam can all make the bed feel less forgiving once the body is trying to cool down. Sleep researchers have spent years studying that cooling process, and many studies point to the same problem.

The brain and body prepare for sleep by lowering core temperature, but excess heat can interrupt that process and pull people out of deeper stages of rest before they fully register what woke them.

A Gallup survey found that 22% of adults identified being too hot as a primary cause of their most recent poor night’s sleep, placing heat behind only physical discomfort and trips to the bathroom. Researchers have also linked warmer nighttime temperatures to shorter sleep duration and more time spent awake after falling asleep.

The Shift Toward ‘Cooling Fixes’ Instead of New Mattresses

Nobody wants to throw out a mattress that is otherwise doing its job. Some premium mattresses can cost thousands of dollars, and most people expect them to last close to a decade, which makes replacing one over a heat problem feel like a steep decision.

The Sleep Foundation notes that for sleepers who are not ready to replace a hot mattress, a cooling topper is often the most practical fix available. Toppers rest on an existing mattress and use materials like gel-infused foam or copper to draw heat away from the body through the night.

Sarah Silverman, a licensed psychologist and sleep wellness consultant cited by the Sleep Foundation, recommends that hot sleepers prioritize "breathable materials" to help the body regulate temperature overnight.

For college students, the same idea applies on a smaller scale. Dorm mattresses are rarely chosen for personal comfort, and students often have limited control over their room temperature or furniture. A cooling topper offers a way to make a standard-issue bed feel more customized without replacing anything they do not own.

Real-World Use Cases: How People Are Solving Overheating

Hot sleepers have been fixing the problem by adding a layer rather than swapping out the whole bed. Someone waking multiple times a night, drenched in sweat, may find that a cooling topper on an otherwise good mattress brings the night back into balance. Couples, on the other hand, often face a different version of the same problem, with one partner sleeping warm while the other runs cold.

Emory University sleep epidemiologist Dr. Dayna Johnson told the American Heart Association that comfort varies by person and that it is “better to think about what is comfortable for you.” A topper on one side of the bed can give each partner more control without requiring a new mattress or turning the thermostat into a nightly argument.

People in warmer climates are also adjusting their beds with the seasons, adding a cooling layer during hotter months and storing it when temperatures drop.

What Makes a Mattress Topper ‘Cooling’?

Cooling toppers are built around a handful of materials, each one designed to tackle the heat problem from a different angle. Gel-infused foam absorbs body heat and disperses it outward rather than letting it pool beneath the sleeper. Latex is naturally breathable, allowing air to circulate through the material and preventing heat from building up.

Copper and graphite are added to some foams specifically for their ability to pull warmth away from the body quickly. And the outer cover matters too, with moisture-wicking fabrics drawing sweat away from the skin so the body can stay cool naturally.

The Sleep Foundation notes that the right combination of these materials determines how well a topper manages temperature through the night. The goal is not to turn a bed cold, but to make the surface less likely to hold onto heat.

Why These Small Changes Can Have a Big Impact

A small change to the bed can alter the night because temperature is tied so closely to how the body prepares for sleep. Psychology Today reported on research suggesting that adjusting the overnight temperature could lead to more than 20 minutes of additional sleep per night.

Once the bed holds less heat, the sleeper has less working against them before and after they fall asleep, and the night stops being interrupted by the restless moments that rising heat tends to cause.

Unlike most approaches to better sleep, which require changes across multiple habits at once, adjusting the sleep surface is a single change that can affect comfort, sleep onset, and overnight wake-ups.

Dr. Heather Hirsch, an internal medicine physician cited by AARP, noted that "you don't need your bedroom to be cold, but you need it to be cool enough to allow your body to cool itself." Reaching that level of comfort, for most hot sleepers, may come down to adding the right layer on top of the mattress.

The Role of Sleep Optimization in Wellness Culture

Sleep has moved well past the simple advice of getting eight hours. More people now treat rest as seriously as nutrition and exercise, recognizing that how well they sleep shapes everything from daily focus to long-term health.

A 2024 study, reported by Yahoo, found that adults who kept consistent sleep schedules had up to a 48% lower risk of death compared to those with irregular patterns, even when total sleep time was the same.

The bedroom itself has become a space people actively design, with lighting, noise, and temperature now treated as specific variables to adjust rather than background conditions to accept. Cooling solutions sit squarely within that mindset, offering one of the more targeted ways to bring a sleep environment closer to what the body needs to rest well.

What This Trend Signals for the Future of Sleep Products

Sleep products are headed in the same direction consumers have been pointing them, toward more personal control over the conditions that shape a night of rest.

Future Market Insights projects the mattress topper category will grow from roughly $1.9 billion in 2025 to $3.39 billion by 2036, with consumers seeking temperature-regulating materials and other flexible add-on solutions.

Nicole Slinger, vice president of product marketing at Ergomotion, told BedTimes Magazine that today's consumers simply “want real fixes,” and manufacturers are responding by making temperature control a foundational part of product design.

Beds are becoming more adaptable as a result, with sleep setups that can be customized to individual bodies and adjusted as needs and seasons change. Cooling is the common thread running through all of it, and how well a product manages heat has become one of the first questions manufacturers now answer.

A Cooler Approach to Better Sleep

Overheating during sleep is one of the most common disruptions people face at night, and for many sleepers, it is a problem with a practical fix. Sara Mednick, a sleep neuroscientist at the University of California, Irvine, told NPR that “we all know what it means to have a bad night of sleep,” and the fix does not have to be complicated or expensive.

People are paying closer attention to what shapes their sleep, and temperature has become one of the variables they are no longer willing to leave unaddressed. Achieving a cooler night, for many people, may require less than they expected.

This story was produced by Sleepyhead and reviewed and distributed by Stacker.