Knowledge
Sourced guides on how the body stays warm, how patients and clinicians are kept comfortable, how crews work safely in cold and heat, and how warming gear works. Pick the theme closest to your world.
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Science of Warmth
For anyone who wants to understand how the body makes, keeps and loses heat.
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Healthcare
For clinicians, perioperative teams and hospital leaders.
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- How to stay warm in the operating room
- What is perioperative hypothermia?
- Forced-air vs conductive warming

Work and Duty
For employers, safety leads, crews, service members and EMS.
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Everyday Life and Health
For people who feel the cold, and for daily life outdoors.
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- Cold sensitivity and Raynaud’s
- Staying warm in everyday life
- Staying warm at home and with family
- Staying warm with a health condition or disability
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Heat and Cooling
For hot jobs, heavy protective gear and personal heat sensitivity.
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Technology and Gear
For choosing, using and caring for warming gear.
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Feeling cold or hot during pregnancy: what is normal and how to stay comfortable
Many people feel warmer than usual during pregnancy because metabolism, blood volume and blood flow to the skin all rise. Feeling always cold during pregnancy is less typical and can be linked to anemia, an underactive thyroid, low blood pressure, poor sleep or inactivity. Gentle warming and cooling are fine, but avoid anything that raises core temperature, such as hot tubs and saunas.
Heated clothing with diabetes or neuropathy: safety first
Heated clothing can be used by many people with diabetes, but neuropathy changes the risk. When nerves cannot sense heat properly, a heated panel, sock or hand warmer can burn skin without warning. Talk to your clinician first, avoid direct heat on numb areas, especially the feet, use the lowest effective setting, keep fabric between heat and skin, and check your skin every time.
Scleroderma, lupus and cold: living well in cold weather
Cold sensitivity is one of the most common experiences in scleroderma and lupus, mostly through secondary Raynaud's. Nearly 90% of people with scleroderma have Raynaud's symptoms, and it affects up to one-third of people with lupus. Living well in the cold means warming the whole body, protecting fragile skin, avoiding sudden temperature changes and reporting sores early to your care team.
Cold intolerance: thyroid, anemia, chemotherapy and other causes
Cold intolerance is an abnormal sensitivity to cold temperatures. MedlinePlus lists its main causes as anemia, hypothyroidism, blood vessel problems such as Raynaud's, anorexia nervosa, problems with the brain's temperature center and chronic severe illness. Some cancer drugs, notably oxaliplatin, also make people very sensitive to cold. A clinician can usually narrow the cause with an exam and blood tests.
Why keeping your core warm helps cold hands
Your body gives up hand warmth first when it senses cold. To protect core temperature, the hypothalamus narrows blood vessels in the skin, and fingers cool quickly. Keeping the torso warm reduces that signal, so the body has less reason to hold warm blood back from the hands. That is why Raynaud's organizations advise warming the whole body, especially the core, not only the fingers.
Gloves and mittens for Raynaud's: what to look for
For Raynaud's, mittens are usually warmer than gloves because fingers share heat inside one space. The most practical setup is a thin liner glove under an insulated, windproof mitten, with room for a hand warmer and a long cuff. Heated gloves suit some people, but no glove works well if the rest of the body is cold, so pair hand protection with core warmth.
Raynaud's vs chilblains, acrocyanosis and other look-alikes
Raynaud's causes short episodes in which fingers or toes turn white, then blue, then red. Chilblains are itchy red or purple patches that appear hours after cold. Acrocyanosis is persistent, usually painless blue discoloration. Erythromelalgia is red, burning skin triggered by warmth. Cold urticaria causes itchy welts within minutes. Buerger's disease is a tobacco-linked artery disease that can mimic Raynaud's.
Primary vs secondary Raynaud's: what the difference means
Primary Raynaud's happens on its own, usually starts in the teens or twenties, and is generally mild. Secondary Raynaud's is caused by another condition, medicine or exposure, often begins later in adulthood, and is more likely to cause finger sores. Clinicians tell them apart with a history, an exam, a look at the nailfold capillaries and blood tests such as ANA.
Cold hands and feet: causes, patterns and practical fixes
Cold hands and feet are usually the body's normal way of protecting core temperature by narrowing blood vessels in the skin. The pattern tells you more than the coldness itself: episodes of white or blue fingers suggest Raynaud's, one-sided coldness can point to blocked arteries, and numbness with cold feet may reflect nerve damage. Most people improve by warming the whole body.
Why am I always cold? Common causes and when to see a doctor
Feeling cold all the time is often a normal difference in how your body conserves heat, shaped by body size, activity and clothing. Persistent or worsening cold can also come from hypothyroidism, anemia, very low body weight, Raynaud's phenomenon or other blood vessel problems. If cold intolerance is long-term, extreme or comes with fatigue or other new symptoms, see a clinician.
Raynaud’s, A Practical Guide To Staying Warm
What Raynaud’s phenomenon is, what triggers episodes, and practical, everyday strategies people use to stay warm. Medically reviewed. Not medical advice.
Cold sensitivity and Raynaud's: a practical guide to staying warm
Feeling colder than the people around you is common and often harmless, but it can also point to Raynaud's phenomenon, an underactive thyroid, anemia or nerve changes. A practical plan has two parts: notice the pattern of your symptoms so a clinician can look for a cause, and build a warmth routine that keeps your whole body, especially your core, comfortably warm.