If you consistently wake up overheated while your partner sleeps comfortably you are not imagining the difference. There are real physiological reasons why some people run hot during sleep and understanding them helps you address the problem more effectively.
Metabolism and Body Heat
Your resting metabolic rate determines how much heat your body generates at rest. People with higher metabolisms produce significantly more body heat than those with lower ones. Since you cannot turn your metabolism down at night the only variable you can control is whether that heat gets trapped against your body or drawn away from it. This is where bedding becomes the critical factor.
Hormones
Hormones are one of the most common causes of running hot at night, particularly for women. During perimenopause and menopause declining estrogen causes the hypothalamus to become hypersensitive to small temperature changes. The result is night sweats and hot flashes where the body triggers a heat-dissipation response to tiny fluctuations that would previously go unnoticed. But hormonal influences on sleep temperature affect people at any age. Thyroid hormones, cortisol levels, and reproductive hormones all influence how much heat your body generates and regulates during sleep.
Body Composition
Muscle tissue generates significantly more heat than fat tissue. People with higher muscle mass tend to run warmer. This is why physically active people often find themselves overheating at night even when they do not have other contributing factors.
Medications
Many common medications raise body temperature during sleep. Antidepressants, particularly SSRIs and SNRIs, are well-known for causing night sweats in a significant percentage of users. Blood pressure medications, hormone treatments, and some diabetes medications can also contribute.
What You Can Actually Change
You cannot change your metabolism or your hormones through bedding choices. But you can change what happens to the heat your body generates. A nylon cooling blanket draws heat away from your skin rather than trapping it, which removes the environmental contribution to overheating regardless of the underlying cause. The Stillwell Cloud is designed specifically for this. See The Cloud here.