A sauna uses intense heat, typically between 150°F and 195°F, to intentionally raise the body’s temperature and induce profuse sweating. This practice is widely embraced for relaxation and its potential cardiovascular benefits when a person is healthy. The decision to enter a sauna while feeling unwell depends entirely on the type and severity of the illness, as the added heat can either offer temporary symptomatic relief or pose serious health risks. Understanding how the body responds to heat stress while fighting an infection is paramount to making a safe choice.
The Risks of Sauna Use During Acute Illness
Using a sauna when suffering from an acute systemic illness, such as the flu or a severe infection accompanied by a fever, places dangerous strain on the body. A fever is an internal regulatory response where the body raises its core temperature to help fight off a pathogen. Introducing external heat from a sauna when the body is already struggling to regulate its temperature can be counterproductive and risks dangerous overheating.
The most immediate danger is rapid dehydration, which is severely exacerbated by intense sweating. Illnesses often cause fluid loss, and a sauna compounds this by inducing an average fluid loss of about one pound in a fifteen-minute session. This rapid depletion of fluids and electrolytes can intensify symptoms like dizziness, headache, and fatigue, potentially leading to fainting or severe complications.
Sauna heat significantly elevates the heart rate, mimicking the effects of moderate physical exercise. The heart is already working harder to manage the inflammatory response during an infection. Adding the cardiovascular demand of a hot sauna can dangerously overtax a system already under stress, particularly for individuals with pre-existing heart conditions. Therefore, any illness characterized by systemic distress, body aches, or a fever is a definitive contraindication for sauna use.
Addressing Mild Cold Symptoms
For very mild symptoms localized to the upper respiratory tract, such as a runny nose, mild congestion, or a slight cough without fever or body aches, the sauna may offer temporary, symptomatic relief. The warm air and increased humidity, especially in traditional saunas, can help to loosen mucus and moisten nasal passages. This effect can briefly clear sinuses and make breathing easier, providing comfort and temporary relief from pressure.
This potential benefit is limited to easing symptoms; the heat does not cure the underlying viral infection or shorten the duration of the cold. The guiding principle for this situation is often referred to as the “neck check.” If all symptoms remain above the neck and are mild, a cautious, brief sauna session may be tolerated.
If symptoms move below the neck, involving chest congestion, deep cough, or body aches, the potential risks outweigh any temporary relief. If a person feels weak, dizzy, or if breathing becomes more difficult in the heat, they must immediately exit the sauna to avoid worsening their condition.
Essential Safety Guidelines and Contraindications
If you are mildly ill and decide a short session is appropriate, strict safety guidelines must be followed to minimize risk. Hydration is paramount, requiring the consumption of water or electrolyte drinks both before and immediately after entering the sauna to compensate for fluid loss. Session duration must be significantly curtailed, with maximum exposure limited to 5 to 10 minutes to prevent overheating and excessive dehydration. To ensure full recovery and prevent a relapse, wait a minimum of 24 to 48 hours after all symptoms have completely disappeared before returning to a normal routine.
Strict Contraindications
Several conditions and substances make sauna use strictly inadvisable. Individuals with existing cardiovascular conditions, such as uncontrolled high blood pressure or recent heart issues, should avoid saunas due to the elevated heart rate. The combination of sauna heat and alcohol consumption is dangerous, as alcohol impairs judgment and the body’s ability to regulate temperature and blood pressure. Certain medications, including diuretics, beta-blockers, and some antihistamines, can interfere with the body’s natural heat-loss mechanisms, increasing the risk of heat stroke.