Staying asleep through the night depends on a handful of controllable factors: your bedroom temperature, what your body does with heat while you sleep, your sound environment, and what you do when you wake up at 2 a.m. Most mid-night waking has a fixable cause, and small changes often produce noticeable results within a few nights.
Why Your Body Wakes Up
Sleep isn’t a single uniform state. You cycle through lighter and deeper stages roughly every 90 minutes, and at the transition points between cycles, you’re vulnerable to waking. Whether you actually wake up depends on what’s happening around and inside you at that moment: noise, temperature, a full bladder, pain, or a spike in stress hormones can all pull you out of sleep during these natural transition windows.
Your core body temperature plays a central role in sleep maintenance. During wakefulness, your core runs warmer and your skin runs cooler. During sleep, that pattern flips: blood vessels near your skin dilate, pushing heat outward, which drops your core temperature. This process produces roughly a 0.15°C per hour decline in core temperature. When that temperature gap between skin warmth and core coolness narrows or reverses (because your room is too hot, for instance), sleep quality and duration worsen. When the gap is large and stable, you stay in deeper sleep longer.
Keep Your Room Between 60 and 65°F
The single most impactful environmental change for staying asleep is cooling your bedroom. Alon Avidan, director of the UCLA Sleep Disorders Center, recommends setting your thermostat between 60 and 65°F (about 15.5 to 18°C). That range supports both falling asleep and staying asleep, because it lets your body shed heat efficiently through the night.
Sleeping in a room between 70 and 75°F, by contrast, is a range that promotes insomnia. When you sleep hot, you tend to stay in lighter sleep stages rather than reaching slow-wave sleep, the deepest and most restorative phase. In those lighter stages, it takes very little to wake you. If you can’t control your thermostat, a fan, lighter bedding, or moisture-wicking sheets can help bridge the gap. Wearing socks to bed, counterintuitively, can also help: warming your feet promotes the skin vasodilation that cools your core.
Rethink Noise Machines
Pink noise and white noise machines are widely recommended for sleep, but recent evidence complicates that advice. A study from Penn Medicine tracked 25 healthy adults across seven nights in a sleep lab and found that pink noise at 50 decibels (similar to moderate rainfall) was associated with a nearly 19-minute decrease in REM sleep. Participants also reported that their sleep felt lighter and that they woke up more frequently compared to silent nights.
When pink noise was combined with external noise like aircraft sounds, deep sleep and REM sleep both shortened significantly, and time spent awake increased by 15 minutes. The consistent finding across all noise conditions was that earplugs outperformed sound masking. Earplugs largely prevented the drop in deep sleep caused by environmental noise, without introducing the REM-disrupting effects of constant background sound. If outside noise is your main problem, foam or silicone earplugs are a better first option than a sound machine.
What to Do When You Wake at 2 a.m.
The worst thing you can do when you wake up in the middle of the night is lie there trying to force yourself back to sleep. This trains your brain to associate your bed with frustration and wakefulness, which makes the problem self-reinforcing over time.
The standard behavioral approach, used in cognitive behavioral therapy for insomnia, is simple: if you can’t fall back asleep within roughly 15 to 20 minutes, get out of bed. Go to another room, do something quiet and low-stimulation (reading a physical book, light stretching, sitting in dim light), and return to bed only when you feel genuinely sleepy again. This works because it preserves the mental link between your bed and sleep rather than between your bed and lying awake. It feels counterproductive the first few nights, but over one to two weeks it typically resets the pattern.
Avoid checking your phone or turning on bright overhead lights. Even brief exposure to bright light suppresses melatonin production and signals your brain that it’s time to be awake. If you need to see, use a dim nightlight or a lamp with a warm, low-wattage bulb.
Melatonin: Form Matters More Than Dose
If you’ve tried melatonin and found it helps you fall asleep but not stay asleep, the formulation is likely the issue. Standard immediate-release melatonin peaks quickly and clears your system within a few hours. Extended-release melatonin, by contrast, stays above the sleep-maintenance threshold for a median of 6.7 hours, compared to just 3.7 hours for the immediate-release version.
That difference matters because your brain’s natural melatonin production sustains levels throughout the night. An immediate-release tablet mimics the initial surge but leaves a gap in the second half of the night, which is when many people report waking. If you use melatonin, look specifically for extended-release or sustained-release formulations. Keep the dose low (0.5 to 3 mg is typically sufficient) since higher doses don’t improve effectiveness and can cause grogginess the next morning.
Magnesium and Evening Nutrition
Magnesium is one of the more evidence-supported supplements for sleep quality. It helps regulate the nervous system’s ability to calm down, and many people don’t get enough from diet alone. The recommended daily intake is 310 to 320 mg for adult women and 400 to 420 mg for adult men, depending on age. Magnesium glycinate is the form most commonly recommended for sleep because it’s well absorbed and less likely to cause digestive issues than other forms like magnesium oxide.
What you eat in the evening also influences whether you stay asleep. Blood sugar that drops too sharply overnight can trigger a stress response that wakes you up. If you tend to wake between 2 and 4 a.m., a small bedtime snack that combines slow-digesting carbohydrates with some protein or fat can help stabilize glucose levels through the night. Good options include a handful of nuts with a few crackers, a small portion of whole-grain cereal with milk, or a banana with a tablespoon of nut butter. The goal isn’t a full meal. Just enough to prevent your blood sugar from bottoming out.
Habits That Protect the Second Half of the Night
Alcohol is one of the most common reasons people fall asleep easily but wake up hours later. It initially acts as a sedative, but as your liver metabolizes it (roughly one drink per hour), it fragments sleep architecture in the second half of the night. Even two drinks in the evening measurably reduce deep sleep and increase nighttime awakenings. If staying asleep is your priority, finish your last drink at least three to four hours before bed, or skip it entirely on nights when sleep quality matters most.
Caffeine is the other major culprit, and its effects last longer than most people realize. Caffeine has a half-life of about five to six hours, meaning half of the caffeine from a 2 p.m. coffee is still circulating at 7 or 8 p.m. For sleep maintenance specifically, a noon cutoff is a safer bet than an afternoon one, especially if you metabolize caffeine slowly (which is genetically variable and hard to self-assess).
Consistency matters more than any single intervention. Going to bed and waking up at the same time every day, including weekends, stabilizes your circadian rhythm and makes it easier for your body to sustain sleep through the full night. Irregular sleep timing is one of the strongest predictors of fragmented sleep, even when total sleep hours stay the same.