From the Guidelines
Exposure to cold weather with wet hair can increase the risk of developing hypothermia and upper respiratory tract infections (URTI), such as the common cold or influenza, due to the potential for cold stress-induced immunosuppression 1.
Key Points to Consider
- The risk of hypothermia and URTI is not unique to wet hair and can be mitigated by dressing warmly and avoiding prolonged exposure to cold temperatures 1.
- In cases where illness does occur, treatment with over-the-counter medications such as acetaminophen (650-1000mg every 4-6 hours) or ibuprofen (200-400mg every 4-6 hours) may help alleviate symptoms, but prevention through proper cold-weather attire and hair drying is recommended 1.
- Cold stress can lead to increased morbidity and mortality from respiratory and cardiovascular diseases, particularly among vulnerable populations such as the young and older people 1.
- Proper housing insulation and heating can help reduce the risk of respiratory and cardiovascular diseases, and improve overall health and well-being 1.
- Some studies suggest that retrofitting insulation and providing heating vouchers can be effective in reducing fuel poverty and improving health outcomes, particularly among vulnerable households 1.
Prevention and Treatment
- Dressing warmly and avoiding prolonged exposure to cold temperatures can help prevent hypothermia and URTI.
- Using over-the-counter medications such as acetaminophen or ibuprofen can help alleviate symptoms of URTI.
- Proper housing insulation and heating can help reduce the risk of respiratory and cardiovascular diseases.
- Providing heating vouchers and retrofitting insulation can be effective in reducing fuel poverty and improving health outcomes.
From the Research
Hypothermia Risk
- Exposure to cold weather can increase the risk of hypothermia, which occurs when the core body temperature falls to 35 degrees C (95 degrees F) or less 2.
- Primary or accidental hypothermia can occur in healthy individuals who are inadequately clothed and exposed to severe cooling, which may include having wet hair in cold weather 2.
- However, there is no direct evidence to suggest that wet hair in cold weather specifically increases the risk of hypothermia.
Upper Respiratory Tract Infection (URTI) Risk
- Exposure to cold has been associated with an increased incidence and severity of respiratory tract infections, including upper respiratory tract infections (URTI) 3.
- Inhaled cold air, cooling of the body surface, and cold stress can cause pathophysiological responses that increase susceptibility to infections, such as vasoconstriction in the respiratory tract mucosa and suppression of immune responses 3.
- However, the relationship between acute cooling of the body surface, such as having wet hair in cold weather, and the onset of URTI is not well established, with some studies suggesting no cause-and-effect relationship 4.
- One study proposed a hypothesis that acute cooling of the body surface may cause reflex vasoconstriction in the nose and upper airways, which could inhibit respiratory defense and lead to the onset of URTI symptoms 4.
Other Health Effects
- Wet hair in cold weather may be a predisposing factor for sinus headache and posterior eye pain, possibly due to the selective brain cooling system 5.
- Exposure to cold weather can cause a range of other health effects, including cold-related illness and death, which are preventable 6.
- Certain populations, such as unsheltered homeless individuals, people who use substances and become incapacitated outdoors, and older adults with medical and psychiatric conditions without home heat, are at increased risk of cold-related illness and death 6.