An infrared (IR) sauna uses specialized heaters that emit light waves, which the body absorbs as radiant heat, directly raising the core temperature. This mechanism differs from a traditional sauna, which heats the air around the user. The flu, or influenza, is a contagious viral infection that attacks the respiratory system, typically causing an abrupt onset of symptoms like fever, body aches, and profound fatigue. Introducing external heat therapy during this viral illness demands careful consideration due to the body’s already compromised state.
Safety Concerns When Using Heat Therapy During Illness
Introducing a heat stressor like an infrared sauna when the body is fighting the flu carries significant risks, primarily centering on fluid balance and thermal regulation. The flu often causes a fever, which is the body’s natural defense mechanism against the virus. Adding external heat to an already elevated internal temperature can push the body into a dangerous hyperthermic range. This added thermal load forces the body to work harder, placing undue metabolic and cardiovascular strain on a system already struggling to combat the infection.
The most immediate and concerning risk is dehydration and electrolyte imbalance. A typical flu infection can cause fluid loss through fever, sweating, and sometimes vomiting or diarrhea. Excessive sweating induced by a sauna session further depletes the body’s fluid reserves and essential minerals like sodium and potassium. This rapid fluid loss can thicken the blood, reduce blood volume, and impair the immune system’s ability to function optimally, potentially prolonging recovery.
The cardiovascular system is also stressed by the combination of illness and heat exposure. Heat causes peripheral blood vessels to dilate, requiring the heart to increase its output to pump blood closer to the skin for cooling. When the body is already fatigued and under stress from the flu virus, this increased cardiac demand can lead to lightheadedness, dizziness, or even fainting.
How Infrared Heat Interacts with Flu Symptoms
Despite the risks, the penetrating heat from an infrared sauna is often considered by people with the flu due to its potential for temporary symptom relief. The radiant heat penetrates deep into the tissues, causing blood vessels to dilate and increasing circulation. This effect can offer a soothing sensation for the intense muscle aches and joint pain characteristic of influenza infections.
Increased blood flow helps deliver oxygen and nutrients to sore areas while assisting in the removal of metabolic waste products that accumulate in fatigued muscles. The warmth may also help alleviate mild upper respiratory symptoms, as the heat and resulting light sweating can temporarily loosen thick mucus and open nasal passages. For some, the gentle warmth of an infrared sauna is more tolerable than the intense heat of a traditional steam sauna for respiratory discomfort.
Any perceived benefit is palliative, focused solely on temporary symptom management, and not on curing the viral infection itself. The concept that induced hyperthermia can significantly boost the immune system or shorten the duration of the flu by mimicking a fever remains a theoretical benefit. While raising the body’s temperature can activate certain immune responses, there is no definitive scientific evidence that infrared sauna use actively treats or accelerates recovery from the influenza virus.
Absolute Contraindications and Usage Guidelines
A person with the flu must understand the absolute contraindications for infrared sauna use to prevent severe health consequences. Any individual experiencing a fever, generally defined as a temperature above 101°F, should avoid heat therapy entirely, as this dramatically increases the risk of overheating and dangerous cardiovascular stress. Severe symptoms such as extreme fatigue, profound weakness, intense dizziness, or signs of respiratory distress also make sauna use unsafe.
Caution must also be exercised regarding medications that are commonly taken during a flu infection. Certain over-the-counter and prescription drugs, including some decongestants, antihistamines, diuretics, and beta-blockers, can impair the body’s ability to regulate its own temperature or affect blood pressure. Consulting with a healthcare provider about how specific medications interact with heat exposure is a mandatory safety step before considering a session.
For those experiencing only very mild symptoms without a fever, and after physician approval, conservative usage protocols must be followed. Sessions should be strictly limited to a maximum duration of 10 to 15 minutes, with the sauna set to the lowest effective temperature setting. Hydration with water or electrolyte-rich beverages must occur before, during, and immediately after the session to counteract fluid loss. If any feeling of nausea, lightheadedness, or increased malaise occurs, the session must be terminated immediately.