Night sweats aren't pleasant. You may wake up so damp and sweaty you'll need to change your clothing or bed sheets. Excessive sweating during sleep, though, is something most people experience at some point in their life.
The cause of night sweats varies. It may be as simple as too many blankets or sleeping in heavy clothes, or the cause could be more complex — a change in hormones, an illness or a side effect of medication or the impact of dietary choices.
Read more: Understanding the Causes of Night Sweats
Illnesses and Hormone Changes
Sweating is a natural process controlled by the autonomic nervous system, the U.S. National Library of Medicine says. It's how the body stays cool. How much you sweat depends on the number of sweat glands you have. Abnormally heavy sweating may be a sign that something in your body is changing.
Night sweats that occur as instances of severe sweating or perspiration, like soaking your bedding or clothes at night, are usually associated with illness, explains Steven Reisman, MD, a cardiologist at the New York Cardiac Diagnostic Center in New York City.
When night sweats are the result of an illness such as tuberculosis, infection, AIDS or certain cancers, other symptoms such as weight loss, fever or cough also occur, he adds. Medications used to treat various health conditions are also known to induce night sweats.
Hormonal changes also can be the reason for night sweats, explains Harvard Health Publishing. With age, bodies naturally produce fewer hormones, but these hormonal changes can occur early for some people, so there is not a magic age for when this might happen.
"Low estrogen in women (menopause) and low testosterone in men can cause night sweats," says Seogeun Hong, MD, an internal medicine doctor with St. Joseph Hospital in Orange, California.
Sweating After Eating Carbs
Carbohydrates are a source of fuel for your body, the American Diabetes Association says. Grains, legumes, fruits and vegetables are good sources of carbohydrates. The amount and types of carbs you eat can have a direct influence on your blood sugar levels. Eating simple carbs may cause blood sugar to rise rapidly and then fall just as quickly, according to Sanford Health, which notes that this crash can cause sweating.
"Sweating after eating is not considered a sign of diabetes," Dr. Hong says. "However, if a patient who takes diabetes medications has sweating, it can be a sign of low blood sugars (hypoglycemia)."
The National Institute of Diabetes and Digestive and Kidney Diseases identifies other symptoms of hypoglycemia during sleep, including having nightmares or crying out and feeling fatigued, irritable or disoriented upon waking.
If night sweats are an issue for you, avoid eating a snack or meal high in carbohydrates right before bed. If you need to have a sweet snack before bedtime, choose something low in sugar and carbohydrates. Also, steer clear of foods and beverages that can trigger sweating, such as alcohol, caffeine and spicy foods, notes the U.S. National Library of Medicine.
What to Do
Dr. Hong offers general guidelines for anyone dealing with night sweats: Use fans to keep cool, wear loose cotton clothing, use cotton bed linens and stay hydrated.
However, actual treatment for night sweats varies with the cause. So, work with your doctor to determine what could be causing your night sweats. If certain foods are the trigger, avoid or limit those foods. If medication is the culprit, your doctor may recommend another treatment option.
"The hot flashes and night sweats due to hormonal changes can be somewhat more challenging [to treat] due to the risks of hormonal replacement therapy," Dr. Hong says. "For women with menopausal hot flashes, hormone replacement can be an option."
However, if other health risks mean hormone replacement is not a good fit, there are several different medications that have been proven to help with the symptoms, she adds.
"For men with testosterone deficiency, testosterone replacement therapy can be initiated with caution," Dr. Hong says. "Testosterone levels should be routinely monitored, and patients should be screened for prostate cancer prior to the treatment.
Is This an Emergency?
- National Institute of Diabetes and Digestive and Kidney Diseases: "Low Blood Glucose (Hypoglycemia)"
- U.S. National Library of Medicine: "Sweating"
- Steven Reisman, MD, cardiologist, New York Cardiac Diagnostic Center, New York City
- Seogeun Hong, MD, internal medicine doctor, St. Joseph Hospital, Orange, California
- Sanford Health: "Sugar Crash Effects and How to Fix Them"
- American Diabetes Association: "Get Smart on Carbs"
- Harvard Health Publishing: "Hot Flashes in Men: An Update"