Why You Get Hot When You Sleep

It’s 2:00 am. You’re flipping and flopping, splashing and sopping. It takes every ounce of remaining energy to keep from sitting up bolt right and screaming “Why do I get hot when I sleep??!!” There are plenty of reasons, so let’s dive into what’s making you sweat and how you can stay cool through the night.

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Your Body’s Built-in Temperature Changes

Your body has its own built-in thermostat, known as your circadian rhythm, which helps regulate your temperature throughout the day and night. Normally, your body cools down as you get ready for sleep, but certain factors can mess with this process. Things like hormone fluctuations, a fast metabolism, or medical conditions can throw off your temperature control and make you feel too warm in bed.

Your Room Might Be Too Warm

Sometimes, the problem is simply your sleep environment. The ideal bedroom temperature for sleep is between 60–67°F (15–19°C), but many people sleep in rooms that are too warm or stuffy. Here’s what might be heating up your space:

Poor ventilation – If your room doesn’t have good airflow, heat gets trapped.
Too many blankets – Heavy comforters and multiple layers can hold in body heat.
Your mattress – Memory foam mattresses, while comfy, are notorious for trapping heat.
Weather conditions – If it’s hot or humid outside, your bedroom can heat up fast.

Your Bedding and Pajamas Could Be the Culprit

What you sleep in can make a huge difference. Some fabrics trap heat, while others let your skin breathe. If you’re overheating at night, check your bedding and pajamas:

Synthetic fabrics – Materials like polyester don’t breathe well, making you hotter.
Flannel sheets – Great for winter, but way too warm in hotter months.
Heavy blankets – Using a thick duvet when it’s warm out can make you sweat more.
Tight sleepwear – Snug-fitting pajamas can trap heat against your body.

Switching to lightweight, breathable materials like cotton, bamboo, or linen can help keep you cool.

Your Metabolism Works Even While You Sleep

Even though you’re resting, your body is still working. Your metabolism doesn’t shut off at night—it keeps burning calories, which produces heat. Some things that can make your metabolism work harder include:

Eating right before bed – Digesting food generates heat, especially big meals.
Exercising too late – A workout close to bedtime raises your body temperature.
Hyperthyroidism – If your thyroid is overactive, your metabolism speeds up, making you feel hotter.

Hormonal Shifts Can Heat You Up

Hormones play a big role in body temperature regulation, which is why some people are more prone to night sweats. Common hormonal triggers include:

Menopause and perimenopause – Hot flashes and night sweats are common symptoms due to changing estrogen levels.
Pregnancy – Increased blood flow and hormonal changes can cause you to feel warmer.
Menstrual cycle – Your temperature naturally rises after ovulation.
Testosterone fluctuations – Some men experience temperature changes due to hormone shifts.

Certain Medical Conditions and Medications

Sometimes, the cause of nighttime overheating is deeper than just room temperature or bedding. Certain health issues and medications can trigger night sweats, including:

Hyperthyroidism – An overactive thyroid speeds up metabolism and body heat production.
Infections and fever – If you’re sick, your body may sweat more to fight off the infection.
Diabetes and blood sugar issues – Low blood sugar can lead to sweating episodes at night.
Stress and anxiety – High stress levels release adrenaline, which raises body temperature.
Medications – Some antidepressants, hormone therapies, and blood pressure meds list night sweats as a side effect.

Alcohol and Caffeine Can Mess With Your Body Temperature

What you drink before bed can also play a role in how hot you feel at night.

Alcohol – It might make you feel relaxed, but it also messes with your body’s ability to regulate temperature, making you overheat later in the night.
Caffeine – Found in coffee, tea, and energy drinks, caffeine speeds up your metabolism and can keep your body temperature elevated.

Your Sleeping Position Matters

The way you sleep affects how much heat gets trapped around your body.

Sleeping on your back – Can make you feel hotter, especially if your mattress holds heat.
Sleeping on your side – Allows for better airflow and heat dissipation.
Curling up – Can trap heat and make you feel even warmer.

If you tend to overheat, try sleeping in a position that lets air circulate more freely around your body.

Your Bedroom Electronics Could Be Warming You Up

A lot of us keep electronic devices in our bedrooms, and they can generate more heat than you’d expect. Common culprits include:

Laptops and tablets – If you use them in bed, they can add extra heat.
TVs and gaming consoles – These produce heat while running, especially in enclosed spaces.
Chargers and LED lights – Even small electronics can warm up your room over time.

Try turning off unnecessary electronics before bed to keep your space cooler.

Tips for Staying Cool at Night

If you’re struggling to stay cool while sleeping, here are some easy fixes:

Lower your room temperature – Aim for 60–67°F (15–19°C) for optimal sleep.
Switch to breathable bedding – Cotton, bamboo, and moisture-wicking sheets help regulate temperature.
Wear loose, lightweight pajamas – Avoid heavy or synthetic fabrics.
Improve air circulation – Use fans, open windows, or invest in air conditioning.
Stay hydrated – Dehydration can make it harder for your body to regulate heat.
Take a cool shower before bed – Helps lower your body temperature before sleep.
Reduce stress – Try deep breathing or meditation to prevent stress-related heat spikes.

Waking up drenched in sweat isn’t fun, but there are plenty of reasons why it happens. Whether it’s your room, bedding, metabolism, or hormones, identifying the cause can help you make simple changes to stay cool at night. Adjusting your sleep setup, tweaking your nighttime routine, and paying attention to your body’s needs can go a long way in improving sleep quality and keeping you comfortable while you rest.