Rheumatoid arthritis (RA) is a chronic autoimmune condition where the immune system attacks the lining of the joints (synovium), causing inflammation, pain, stiffness, and joint damage. Managing RA symptoms requires a multifaceted approach, often combining medication with lifestyle adjustments. Many people with RA explore complementary therapies, such as sauna use, as a non-pharmacologic method to improve their quality of life. Evaluating the evidence on heat therapy helps determine its role as a supportive tool in an RA management plan.
How Heat Therapy Alleviates Joint Discomfort
Sauna heat offers immediate, localized relief from the characteristic morning stiffness and joint pain associated with RA. The warmth causes blood vessels surrounding the affected joints to widen (vasodilation), increasing local blood circulation. This surge in blood flow delivers more oxygen and nutrients while flushing away metabolic waste products that contribute to discomfort. Increased tissue temperature also promotes the relaxation of muscles that often tense up protectively around painful joints. This relaxation temporarily reduces overall stiffness, potentially improving range of motion immediately following a session.
This relief offers a valuable window of opportunity for gentle stretching or physical therapy. Furthermore, the heat stimulates the release of endorphins, the body’s natural pain-relieving compounds. These compounds interact with brain receptors to produce an analgesic effect, helping to mute the perception of joint pain and enhance overall feelings of well-being.
The Systemic Impact on Inflammation Markers
Beyond localized joint effects, regular sauna use can trigger systemic physiological responses that may influence the underlying pathology of RA. Exposure to intense, short-term heat stress (hyperthermia) has been shown to modulate the body’s inflammatory pathways. Consistent, long-term sauna use has been associated with a reduction in key inflammatory markers, such as C-reactive protein (CRP) in the blood. Studies suggest this systemic anti-inflammatory effect may be similar to that achieved through moderate exercise.
Sauna therapy also influences the production of pro-inflammatory cytokines, which are signaling molecules that drive the autoimmune response in RA. Reductions in molecules like Interleukin-6 (IL-6) and Tumor Necrosis Factor-alpha (TNF-α) have been observed with regular heat exposure. These changes indicate a potential for sauna use to temper the systemic inflammation that contributes to joint destruction and associated cardiovascular risks. Since people with RA face an elevated risk of heart disease, the vasodilation induced by saunas improves endothelial function, contributing to better heart health. Regular sessions may also help regulate cortisol, the primary stress hormone, which can indirectly manage the stress response heightened in chronic autoimmune conditions.
Choosing the Right Sauna and Session Length
For individuals with RA, the type of sauna and session duration are key considerations. Far-infrared (FIR) saunas are often preferred over traditional Finnish or steam saunas because they operate at lower ambient air temperatures, typically between 120°F and 140°F (45°C to 60°C). Unlike traditional saunas that heat the air, FIR saunas use light to directly warm the body, allowing for deeper tissue penetration. This direct heating provides therapeutic warmth to muscles and joints without requiring the user to tolerate the intense heat of a conventional sauna.
Starting with shorter sessions is recommended to assess tolerance and prevent overheating. A session length of 15 to 20 minutes is a reasonable starting point for those new to heat therapy. A frequency of two to three times per week is commonly recommended for managing chronic symptoms. For those aiming for a reduction in systemic inflammation markers like CRP, some research suggests four to seven sessions per week may be more beneficial, though this must be gradually introduced and closely monitored.
Important Safety Considerations for Patients
Before beginning any form of heat therapy, it is essential to consult with a rheumatologist or other healthcare provider. This ensures that sauna use is appropriate for the individual’s specific disease activity and current treatment regimen. The most important safety consideration is to avoid using a sauna during an acute inflammatory flare-up. When joints are visibly hot, swollen, and red, applying external heat can potentially worsen the inflammation and increase pain.
People with RA must also be mindful of potential interactions with their prescribed medications. Certain drugs, including some blood pressure medications and diuretics, can affect the body’s ability to regulate temperature or increase the risk of dehydration. Staying well-hydrated before, during, and after a session is mandatory to compensate for fluid loss through sweating. Anyone experiencing dizziness, lightheadedness, or increased pain should immediately exit the sauna and discontinue use until speaking with their doctor.