Cardiologists do not recommend sauna usage for everyone; however, many cardiologists do believe that, for some people, consistent sauna use can reduce their risk of developing cardiovascular disease and, for certain individuals, may be a safety risk. Therefore, it is important to note that cardiologists may have differing opinions on sauna usage and the effects sauna bathing may have on an individual's health or cardiovascular system, depending on their background and experience. To understand why there are differences in opinion among cardiologists about sauna usage and the benefits it may provide to heart health, it is important first to understand how saunas work on the cardiovascular system. The extreme heat typically found in saunas (air temperatures between 80°C and 100°C (176°F and 212°F)) raises the skin temperature very quickly, triggering the body's response of vasodilation (dilating of blood vessels) and causing the heart rate to increase from a normal resting heart rate of 60-70 bpm to a heart rate of approximately 120-150 bpm. This physiological response mirrors a low to moderate amount of physical activity; thus, sauna usage can help improve blood circulation and decrease the stiffness of arterial walls.
The Kuopio Ischaemic Heart Disease Risk Factor Study of Finland and other long-term studies have demonstrated that frequent sauna bathing, four to seven times each week, significantly reduces the risk of sudden cardiac death, fatal coronary heart disease, and all-cause mortality. The Kuopio study found that for men who bathed in a sauna four to seven times per week, the risk of sudden cardiac death was 63% less than those who only bathed once a week. Nevertheless, because these studies are observational in nature (i.e., they show correlation only, rather than definite causation), cardiologists exercise caution in drawing conclusions about how sauna bathing contributes to health. Most of the participants were otherwise healthy, and any positive effect attributed to sauna use may result from healthy lifestyle choices that are made by regular sauna users.
Sauna Use for:
Individuals with Stable Cardiovascular Conditions
Cardiologists have generally had a favourable view of recommending sauna use to patients with stable cardiovascular conditions, especially to patients who complement their exercise programme with sauna use or to those seeking to manage mild hypertension. Patients who have well-controlled high blood pressure experience the heat-induced vasodilation that occurs in the sauna, and as a result, experience a temporary lowering of blood pressure following a sauna session. There is evidence that regular sauna bathing can have beneficial effects on the functioning of the endothelium, the inner lining of blood vessels and on reducing oxidative stress, both of which are critical to preventing the development of atherosclerosis.
Patients with stable chronic heart failure who are receiving close medical supervision may benefit from participating in monitored sauna sessions.The American Journal of Cardiology published findings from research indicating that sauna therapy ("Waon therapy" in Japan; repeated use over time) has been shown to improve cardiac functioning, decrease pulmonary congestion, and increase quality of life for those suffering from heart failure. However, the American College of Cardiologists states that sauna use only upon medical recommendation – with strict monitoring and control over temperature (usually a maximum of 60 Celsius) and time limits (sometimes up to 15 minutes) – as a complement to, not as a replacement for, medication/other standard methods of treatment for heart-failure.
The American College of Cardiologists provides examples when to avoid sauna usage due to safety concerns. The most severe example is in patients with unstable coronary artery disease (e.g., individuals who have just experienced a myocardial infarction or whose angina has not been controlled). The rapid increase of heart rates and workloads associated with the use of heat could cause either ischemia or arrhythmias, and this may occur quickly in patients who already have a significant amount of vascular occlusive disease or weakened heart muscle.
Patients who may have advanced aortic stenosis (aortic valve stenoses) or heart failure (decreased ejection fraction) should also avoid saunas. The heat increases the extent of vasodilatation of the vessels supplying blood to the brain and heart (hypotension); thus leading to loss of consciousness, seizures, and/or cardiac arrest.There is an increased risk of sauna-related health issues due to dehydration, low electrolyte levels, or using medications that can decrease the body's ability to control temperature and make up for fluid losses, such as beta-blockers and diuretics. Also, combining alcohol use with saunas can impair decision-making and lead to dehydration and subsequent cardiac arrhythmias.
General Recommendations from Cardiologists
While it is clear that evidence suggests a need for caution, most cardiologists have taken a middle course when evaluating sauna use. For instance, while most healthy adults (those without known heart problems) should be able to safely use a sauna, cardiologists recommend a few guidelines:
Limit sauna sessions to 15-20 minutes. Moderate sauna temperatures (80-90° C) should be utilized. Always hydrate before and after sauna use. Avoid sauna use immediately after eating heavy meals or exercising vigorously. Listen to your body's warning signs: if you experience dizziness, tightness in your chest, or heart palpitations while in the sauna, get out immediately and cool down slowly.
When assessing the safety of sauna usage among patients who have been diagnosed with heart disease, it is advisable for all cardiologists to consult with the patient's physician to ensure the safety of sauna usage. For patients with heart disease, cardiologists generally recommend that patients allow their heart rate to stabilize and monitor symptoms as they progress to a sauna routine. Some cardiologists potentially include sauna usage within cardiac rehabilitation programs to provide heat therapy, but always under the guidance of a physician. The American Heart Association has not issued any formal recommendations against using saunas, however, most experts of the American Heart Association agree that the moderate use of saunas is unlikely to pose any serious health risks for low-risk populations.
Summary and Conditional Recommendation
To summarize, although cardiologists do not recommend sauna use as the sole method of managing cardiovascular health, cardiologists recognize that sauna usage can be beneficial for many patients if their use is done correctly. Most studies show that the best benefit of sauna therapy is for the long-term reduction of cardiovascular disease risk, particularly in healthy individuals, while caution must be taken with unstable or advanced heart disease. Before beginning any type of sauna usage, all cardiologists recommend prospective patients first discuss sauna usage with their physician, as the physician can assess the patient's risk factors, current medication regimen, and overall heart health. While saunas may provide a warm and relaxing environment for many individuals, sauna therapy cannot be substituted for established medical therapies, a well-balanced diet, exercise, and routine visits to a physician. For the mass population, the answer is "yes-if the person is cautious." Thus, sauna use is a tool, not a cure.
