In addition to helping you relax and cope better with stress, sauna bathing can also improve your health in many significant ways.
There is a growing body of research that supports the conclusion that sauna bathing improves your heart health, and we know more than ever before about the many ways that this occurs.
When you engage in passive heat therapy, such as with a sauna, you are improving blood flow, reducing blood pressure, and improving the function of various arteries and vessels that bring blood and oxygen to your body.
Over time, repeated sauna use is associated with a healthier heart, fewer heart problems, and a decreased risk of death from heart-related issues.
Below, we summarize the results of nearly 30 separate research studies on the effects of sauna on cardiovascular health.
These authors suggest implications for clinical practice as well as future research in this area, and when you examine these studies collectively, you see just how powerful sauna bathing is when it comes to taking care of your heart.
Sauna Use Reduces Risk of Death from Heart Problems
Recent research from Europe has examined the connection between regular sauna bathing and the risk of death from cardiovascular disease.
This study, published in 2018, sought to uncover whether knowing information about patients sauna habits could help improve predictions of their risk of mortality due to heart disease (1).
Using data collected from a group of 1688 men and women ranging in age from 54-74 years old, researchers examined assessment data previously collected to assess sauna bathing habits.
Data came from a study of Finnish men and women known as the Kuopio Ischemic Heart Disease (KIHD) Study.
Researchers in this study collected data on several factors for thousands of people, including data on sauna bathing, clinical characteristics, biomarkers, and fatal cardiovascular disease outcomes, which were analyzed for the purposes of this study.
Once the data were organized, researchers analyzed these to investigate the relationship between the frequency and duration of sauna use with the death rate from cardiovascular disease.
In the 15-year follow up to the original study, there were 181 fatal heart events.
What researchers found in the data was that the risk of death from cardiovascular disease decreased linearly with an increase in the number of sauna sessions per week.
The duration of sauna use, as measured in the number of minutes per week, was inversely associated with death from heart-related events.
Researchers concluded that sauna bathing improves the prediction of your long-term risk for death from cardiovascular disease and that the longer and more frequently you use a sauna, the more you lower your risks from this disease.
Sauna Use Promotes the Development of New Blood Vessels
In 2016, researchers wanted to explore the effects of heat therapy on angiogenic signaling (2).
Angiogenesis is the process by which your body creates new blood vessels from pre-existing ones, which plays a critical role in development, wound healing, pregnancy, and much more.
The building of new blood vessels also is essential for disease prevention and management, including cancer, AIDS, rheumatoid arthritis, and other inflammatory conditions.
For angiogenesis to occur, many complex processes must occur, and these rely on an extensive signaling network within the body.
Past research has revealed that heat therapy, which could include sauna use, can promote the growth of new capillaries within the skeletal system.
In animal trials, it also encourages new vessel growth in the heart.
Investigators in this study evaluated the effects of heating the thigh and the lower body on the expression of various angiogenic regulators and heat shock proteins.
What they found was that heat therapy is a noninvasive and simple technique for activating angiogenic signaling and promoting vascular growth in specific muscles.
While the study did not show improved circulation of certain proangiogenic cells, it is believed this was due to the use of lower temperatures than a typical sauna, which has been shown to produce this effect in other studies.
The use of heat therapy to promote healing and improve vascular capacity is warranted, based on these results.
The authors suggest different modalities, depending on the need, including dry sauna use, to promote healing and overall blood vessel formation.
Using a Sauna Can Help Treat Peripheral Artery Disease
Researchers from Indiana investigated whether leg thermotherapy, a type of heat therapy, could improve the circulation of cytokines as well as vasoactive mediators in patients with symptomatic Peripheral Artery Disease or PAD (3).
The use of water-circulating garments to apply heat to a specific area of the body is a well-documented approach to improving circulation.
Investigators wanted to know the specific effects of this therapy related to blood pressure, blood flow, and the circulation of anti-inflammatory mediators that could help treat or prevent vascular diseases like PAD.
Researchers recruited 16 patients with PAD, and each completed three experimental sessions in random order.
One session involved the use of thermotherapy, one involved exercise testing, and one was the control intervention.
The thermotherapy garment was perfused with water that was heated to 46 degrees Celsius, and patients used it for 90 minutes.
In the control intervention, the water was at 33 degrees Celsius.
Ten of these patients were measured for blood flow in their popliteal artery using an MRI.
Compared with the control intervention, those using thermotherapy had a significant reduction in their systolic and diastolic blood pressure, which lasted for up to two hours after the treatment.
After heat therapy, levels of endothelin-1, a vasoconstrictor, were also reduced.
Blood flow velocity was also increased.
This study shows that heat therapy can reduce blood pressure and improve blood flow, which has positive therapeutic implications for patients with PAD.
Sauna Bathing Reduces Your Risk of Death
The purpose of this 2015 study by researchers in Finland was to follow up on longitudinal data on sauna bathing to determine if this practice reduces the risk of death by cardiovascular causes or all-cause mortality factors (4).
The wanted to investigate the association between duration and frequency of sauna use with the risk of either sudden cardiac death, fatal coronary heart disease, fatal cardiovascular disease, and all causes of death.
Using data from the Kuopio Ischemic Heart Disease Risk Factor Study, researchers selected a sample of 2315 men from Finland, a country known for its habits of sauna bathing.
The data were collected between 1984 and 1989, including information on the frequency and duration of sauna bathing.
During follow-ups 20 years later, information was gathered regarding death rates and causes of death.
The analysis was performed on the data set to determine any correlation between the number of sauna sessions per week, the duration of sauna exposure per week, and causes of death.
The results pointed to a greater risk of sudden cardiac death among participants who used the sauna less frequently or for less time.
The more time participants spend in the sauna each week, the lower their risk of death from not only cardiovascular issues but from all causes of mortality.
The researchers concluded that increased frequency of sauna bathing could be linked to a reduced risk of death from sudden cardiac incidents, cardiovascular disease, coronary heart disease, or other causes of death.
Sauna Use Associated with Reduced Risk of Cardiovascular Death
In a recent study published in Progress in Cardiovascular Diseases, researchers reviewed the evidence on sauna bathing to understand its application for preventing sudden cardiac death (5).
While sudden cardiac death (SCD) is a global health problem, many people who die this way lack the atherosclerotic risk factors associated with this cause of death.
In an attempt to explore additional factors that may be involved in cardiovascular health, the researchers investigated sauna use, which has long been linked to a reduced risk of adverse cardiovascular disease and non-cardiac outcomes as well as mortality.
Reviewing the available studies linking sauna bathing and sudden cardiac death, the authors postulated the mechanisms of action that are responsible for these associations while also outlining the areas of research that are still unclear in this area.
In their extensive review of all the studies available, the concluded several vital points.
First, observational data support that use of sauna bathing to reduce the risk of sudden cardiac death.
When combined with physical activity, sauna use further decreases cardiovascular death risks compared to either activity alone.
Those reports that have linked sauna use to sudden cardiac death can be attributed to other factors, including dehydration, hypertension, and alcohol consumption.
Sauna use is safe, even for those with cardiovascular disease when they use it with caution.
The mechanisms for action reported in the literature include a reduction in arterial stiffness, decreases in oxidative stress and inflammation, improvements to serum lipids, and stabilization of the autonomic nervous system.
The authors support the investigation of sauna use to promote sudden cardiac death prevention as well as a tool to promote relaxation and well-being.
Sauna Poses Little Danger to Those with Cardiac Problems
Often, cardiologists will caution those with heart problems to avoid sauna use, but this wisdom is being questioned in the scientific literature.
The researchers in this 2015 study from the Netherlands examined whether these precautions are medically necessary or even accurate (6).
In reviewing the data on sauna-related deaths, the authors noted that many of the deaths (44 percent) reported in saunas could be attributed to alcohol use while a much smaller percentage was related directly to cardiovascular disease.
Additional research supports this claim, showing that the annual rate of death in saunas is less than 2 per 100,000 people.
In one-quarter of these cases, the cause of death was deemed to be exposure to heat.
The authors noted more recent research that supports the use of sauna bathing by those with hypertension, heart disease, or with a history of a heart attack.
Those with congestive heart failure are also at no more risk than the general population.
In fact, the authors found substantial research to support the use of sauna bathing to improve heart function, lower blood pressure, and reduce the risk of death from cardiovascular problems.
Those who use a sauna regularly have a higher tolerance for exercise and improved endothelial function as well as fewer issues with arrhythmia.
The authors noted that doctors should revise their recommendations when it comes to sauna use, given the vast library of research pointing to its ability to improve cardiovascular health.
The rule of thumb should be that, if you are healthy enough to walk into a sauna, you are not an increased risk from suffering adverse effects because of using one, and it may be of more benefit to your heart than you realize.
Sauna Use Increases Tolerance for Exercise
Researchers in Japan have added to the body of knowledge of sauna use and heart health with their 2005 investigation on the effects and safety of sauna bathing for patients with congestive heart failure or CHF (7).
At the time of the study, there was little evidence available on the influence of the high heat of a sauna on those with chronic heart problems, including CHF.
15 patients who had been hospitalized with CHF were included in the study, and all were deemed to be in stable condition and undergoing conventional treatment for their condition.
Every day for four weeks, the patients engaged in sauna bathing.
There were no adverse effects noted for any of the study participants.
In 13 of the 15 patients, symptoms improved after four weeks.
These improvements included a reduction in systolic blood pressure with no effects on heart rate.
Left ventricular ejection was significantly increased, as well.
Those who used the sauna also had improved tolerance for exercise, as indicated in their walking distance at a six-minute mile pace.
They also had increased oxygen uptake and an improved anaerobic threshold, and all participants had lower levels of both epinephrine and norepinephrine.
This group also had lower numbers of hospital admissions for CHF after the study.
The researchers concluded that sauna bathing was safe for those with congestive heart failure, and regular practice could improve symptoms while also enhancing tolerance for prolonged exercise.
When combined with traditional therapy, sauna bathing could become an effective treatment for cardiovascular problems.
Sauna Bathing Can Improve Heart Function
The group of European researchers behind this 2018 study investigated whether sauna bathing induced changes in the heart associated with improved cardiac function.
They wanted to explore the effects of this practice on arterial stiffness, blood pressure, and several blood-based biomarkers (8).
The study’s participants included 102 men and women who all had at least one cardiovascular risk factor.
Each of the subjects had a single sauna session of 30 minutes at 73 degrees Celsius and between 10 and 20 percent humidity.
Blood and other cardiovascular measurements were taken before, immediately after and 30 minutes after the sauna session.
The results indicated a decrease in femoral pulse wave velocity as well as both systolic and diastolic blood pressure.
The systolic levels remained lower than pre-sauna levels after the 30-minute recovery.
Researchers concluded from these results that sauna bathing has positive effects on arterial stiffness, blood pressure, and some biomarkers of cardiovascular health, including plasma creatinine.
This research adds to the existing findings that support the use of sauna bathing to improve cardiovascular function and reduce the risk of death from heart-related problems.
Sauna Use Compliments Exercise Therapy in Treatment of Heart Failure
Japanese researchers in 2016 wanted to determine if sauna therapy combined with exercise training could improve the condition of patients with chronic heart failure (9).
The examined the cardiac function as well as subjective symptoms, daily activity, and the capacity of patients to get around during their study to determine if adding sauna bathing to a conventional exercise therapy regimen could improve patient progress.
The study involved 54 patients, half of which were given repeated sauna therapy and exercise, and half of which were given only repeated sauna therapy.
Each group received their treatment once a day, five days per week during the study.
At admission and at the time of discharge, researchers measured patients’ brain natriuretic peptide concentration, cardiac function, heart size, and ambulation capacity.
They also noted the patients’ clinical symptoms as well as their ability to perform tasks related to daily living.
Both groups had improvements in heart function, brain natriuretic peptide concentration, cardiothoracic ratio, and left ventricular ejection fraction as well as enhancements in their ability to move around and care for themselves.
Those who used the sauna had more improvements in several key areas, including heart function, ambulation capacity, and their ability to engage in daily activities.
In fact, this last indicator saw the most improvement between the two groups.
The authors concluded that the addition of exercise to the repeated sauna therapy improved cardiac function and the ability to perform daily activities for those with chronic heart failure.
While repeated sauna therapy is known to help improve heart capacity and vascular function, when it is combined with exercise, it becomes an even more powerful took for helping those with heart failure.
Sauna Use is Safe and Beneficial in Treating CHF
In a pilot study performed at the Mayo Clinic, researchers in 2009 sought to examine the effects of sauna bathing on those with chronic heart failure to determine if this practice was safe (10).
They discussed the impact of this therapy on exercise tolerance as well as neuroendocrine concentrations.
This was a randomized, controlled, cross-over trial.
The participants of this study included six men and three women who were admitted to this hospital for chronic heart failure.
They ranged in age between 62 and 87 and were rated on the New York Heart Association Classification rankings as Class III or IV.
They were divided into two random groups and each maintained their normal activity levels and medication regimens.
The first group received 15-minute sauna sessions three times per week for four weeks.
Each session was at 60 degrees Celsius.
After one month, the treatments were reversed.
Researchers examined several measures, including patient acceptance of sauna bathing, scores on the Minnesota Living With Heart Failure Questionnaire, exercise duration on a treadmill, and blood tests to measure adrenaline, noradrenalin, aldosterone, atrial natriuretic factor, adrenomedullin, and endothelin.
No patients reported adverse effects, and the sauna bathing was well tolerated.
While improvements on the Minnesota Living With Heart Failure Questionnaire and treadmill endurance test did not improve enough to reach statistical significance, there was a more marked changed after sauna bathing than during the control phase.
There were no statistically significant differences in brain hormone changes except for noradrenalin, which decreased 24 percent after sauna use.
Under the controlled and supervised conditions of this trial, sauna bathing as deemed to be safe for people with chronic heart failure.
Researchers considered it essential to continue studying the effects of sauna bathing on heart patients to further explore its potential benefits.
Sauna Use Promotes Improved Heart Function
Researchers in Israel wanted to explore the effects of sauna use in patients with chronic heart failure, as well.
Their 2007 study examined the information currently available through medical research on this topic to explore future lines of inquiry (11).
In examining the literature up to this point, the authors summarized that sauna bathing has been shown to be well tolerated in patients with chronic heart failure and that it can improve the hemodynamics in patients with this condition.
The authors examined animal trials, clinical studies, and research on both healthy patients and those with chronic cardiac problems to determine what, if any, we can learn.
Their conclusions are as follows.
According to the collective research:
- Repeated sauna therapy at 60° C for 15 min can improve hemodynamic indicators, clinical symptoms, cardiac function, and vascular endothelial function in patients with chronic heart failure.
- Sauna treatment is considered safe for patients with chronic heart failure who are in the New York Heart Association Class I, II, or III.
- Sauna therapy can improve the cardiac index, mean pulmonary wedge pressure, systemic and pulmonary vascular resistance, and cardiac function.
- Sauna use may help improve clinical symptoms and hemodynamic parameters of patients with chronic heart failure whose endothelial function is impaired.
Sauna Use is Safe for Those with Cardiac Arrhythmias and Ischemic Episodes
Researchers have known for several decades that sauna use should be considered to be safe for patients with certain types of heart conditions, as evidenced by this study from 1983 (12).
German researchers examined the incidence of both cardiac arrhythmias and ischemic episodes during both sauna bathing and swimming to compare these to other types of physical activity that are often recommended to heart patients.
Participants were 18 patients with coronary disease as well as 18 healthy patients as a control group.
Participants had a lower heart rate during swimming or sauna bathing than with cycling.
Patients with a coronary disease showed elevated angina or ST-segment displacement compared to control patients.
The test group also experienced more frequent ventricular premature beats (VPBs), and two patients experienced repetitive VPBs during sauna sessions.
No ischemic events were noted during sauna bathing.
The results of this research, though, still indicated that the use of sauna and swimming is safe for those with coronary conditions, provided they are given appropriate exercise and ECG tests before beginning to ensure they are not at risk.
Long-Term Sauna Use Lowers Blood Pressure
In this study from 1992, researchers examined the long-term effects of sauna bathing on various markers of heart health, including blood pressure (13).
The German researchers studied sauna bathing in those who had been practicing one and three years to see how it influenced blood pressure, heart rate under rest, and under load.
The 65 patients in this study had all been previously diagnosed with hypertension and coronary heart disease and each had undergone aortocoronary venous-bypass surgery.
Each visited a Finnish-style sauna twice per week.
This group was compared to 68 hypertensive patients who regularly engaged in kinesiotherapy involving running and swimming.
Results indicated that both exercise and sauna bathing were effective in regulating blood pressure and hemodynamics in patients with coronary heart disease.
As a therapy for high blood pressure, sauna bathing could be considered to be a viable option, especially for those with limited mobility.
Sauna Bathing Could Assist Recovery from Heart Transplant Surgery
Because of its benefits in reducing blood pressure and enhancing hemodynamics, sauna use could be helpful for patients who are recovering from heart transplantation.
This 1993 study from Germany sought to investigate that (14).
The eight male patients in this study had a median age of 42 years old and had each undergone heart transplant surgery.
Measurements of blood pressure, heart rate, and changes in the hemodynamics of both small and large blood vessels were recorded.
Patients then underwent a single sauna session.
Both systolic and diastolic blood pressure decreased.
There was also improvement in the microcirculation of small vessels.
Improvements in left ventricular ejection fraction and total peripheric vascular resistance were also noted.
While this study was small in scale, it does indicate the possibility of using sauna therapy to improve the outcome for those undergoing heart transplant or other types of cardiac surgery.
More research is needed to understand the long-term effects on these types of patients.
Sauna Bathing and Cold-Water Immersion Safe for Heart Patients
Cold-water immersion, such as diving into icy water, is a widespread practice in Finland after sauna bathing.
While this practice poses no risk to healthy individuals, the effects of this practice are unknown on those with heart failure.
A 2016 study from Switzerland was conducted to examine this effect (15).
37 males were selected for this experiment. 12 had chronic heart failure, 13 had coronary artery disease, and 12 were healthy control subjects.
Participants had two consecutive sauna sessions at 80 degrees Celsius, followed by head-out immersion in 12-degree Celsius water.
Cardiac output was measured with an inert gas rebreathing method before and after sauna and cold-water exposure.
Blood pressure was taken before the sauna, twice during saunas, and after the sauna sessions.
Heart rate variability measurements were also taken.
All participants tolerated the sauna and cold-water immersion well.
In most groups, cardiac output and heart rate all increased significantly after sauna and cold-water immersion.
The exception was the coronary artery disease group following sauna exposure.
All groups experienced a significant decrease in systolic blood pressure during sauna sessions.
And all groups also had a significant increase in systolic blood pressure after cold-water immersion.
Researchers concluded from the results of this study that acute exposure to Finnish sauna and cold-water immersion created similar changes in hemodynamics for chronic heart failure patients as well as healthy individuals.
There was no excessive increase in adrenergic activity or complex arrhythmias that would raise concern for heart patients who wish to engage in these activities.
This practice is deemed safe for those with heart failure of coronary artery disease.
Heat Therapy can Improve Vasodilation in CHF Patients
Researchers in Japan investigated the effects of heat therapy, including sauna use, on patients with congestive heart failure in 1995, yielding some of the earliest research on this topic.
The study, which was published in the journal Circulation, examining the hemodynamic effects of thermal vasodilation in patients with congestive heart failure (16).
The study participants included 34 patients with chronic congestive heart failure.
Using the New York Heart Association Classification system, they were categorized as Class II (2 subjects), Class III (19 subjects), and Class IV (13 subjects).
Patients participated in either a warm-water bath at 41 degrees Celsius for 10 minutes or a sauna bath at 60 degrees Celsius for 15 minutes.
Measurement of blood pressure, electrocardiogram, echo-Doppler, expiration gas, and intracardiac pressures were recorded before, during, and 30 minutes after the bathing period.
Oxygen consumption and heart rate increases were similar for both the treatment conditions.
Neither group had significant changes in systolic blood pressure.
Those in the sauna group had significant decreases in diastolic blood pressure over the warm-water bath group.
Sauna bathing caused decreases in the mean pulmonary artery, mean pulmonary capillary wedge, and mean right atrial pressures while warm-water bath caused increases in these areas.
Both treatments saw a decrease in mitral regurgitation, which is common in patients with CHF.
Researchers concluded that both warm-water baths and saunas help to improve hemodynamics in those with congestive heart failure.
This is likely due to a reduction in cardiac load.
Thermal vasodilation should be considered as a therapeutic tool when considering options for patients with CHF.
Sauna Use Improves Vascular Health
In 2016, researchers from Harvard Medical School undertook a review of the literature to explore the effects of passive heat therapy on vascular health (17).
By examining the results, limitations, and explanations from current research, the medical community can gain a greater understanding and devise new research studies that will provide unknown answers to essential questions.
By examining the research, including one 30-year study of sauna use, researchers concluded that repeated elevation of the core body temperature could create more positive generalized effects on vascular health than previously understood.
These effects include improvements in arterial stiffness, endothelial dilation, blood pressure, and more.
The changes that are induced by repeated and prolonged sauna use are consistent with improved cardiovascular health.
And results of this type have been noted in both healthy individuals as well as those with cardiovascular problems.
The review also noted some inconsistencies revealed in the research on sauna use.
For example, carotid artery stiffness and compliance were not changed by heat therapy, but thickness was decreased.
Heat therapy may be insufficient to yield functional alterations of the heart structure in some cases.
There are also changes in the stiffness of the femoral artery that are inconsistent with long-term changes to the muscles.
The review also discussed clinical applications for these findings.
Heat therapy is widely accessible, safe for both healthy and diseased individuals, and is cost-effective.
Because of its ability to decrease other markers of disease, like cholesterol, those with limited mobility should consider heat therapy as an alternative to exercise training.
It can be used to supplement other forms of treatment for those with heart failure of spinal cord injuries, which reduce one’s ability to engage in exercise.
The conclusion was that heat therapy, such as sauna bathing, has a lot of positive effects that could help many people with a range of health conditions.
Combining Exercise and Sauna Bathing Increases Cardiovascular Fitness Results
The researchers in this 2018 study published in the Annals of Medicine focused on the effects of sauna bathing on cardiorespiratory fitness (18).
Cardiorespiratory health refers to how you are your circulatory and respiratory systems supply oxygen to your skeletal muscles during physical activity.
Understanding the relationships between this indicator of heart health and sauna bathing on the various causes of death was the focus of these researchers.
The study included 2277 men.
Their cardiorespiratory fitness was measured by respiratory gas analyses and categorized as low or high.
The level of sauna exposure was established at baseline and classified as low (less than twice per week) or high (three to seven sessions per week).
Follow-up data was collected 26 years after baseline collection.
Results indicate that high cardiorespiratory health and frequent sauna bathing were associated with lower mortality risk.
The results were more positive than those for high fitness or high sauna use along.
While increased sauna use and improved cardiorespiratory fitness are independently associated with reduced mortality risk, the combination provides additional survival benefits.
Those with the highest incidence of sauna use and cardiorespiratory fitness had the lowest rate of death from all causes.
Researchers concluded that staying healthy and using a sauna regularly could extend lifespan.
High Temperatures in Sauna Bathing Linked to Improved Cardiovascular Function
Researchers in Japan explored the effects of how water on cardiovascular function (19).
This study from 2018 examined the effects of bathing frequency and water temperature to examine the influence of elevated temperatures on hemodynamics.
Examining 873 subjects, researchers measured the thickness of the carotid artery as well as the brachial-ankle pulse wave velocity.
Waveform analyses of the radial pulse was also conducted.
Measures of a natriuretic peptide in the blood were also collected to show cardiac loading.
Baths lasted around 12 minutes.
Those who took five or more baths per week had lower pulse wave velocity, central pulse pressure, and levels of natriuretic peptides.
Sample results were noted upon follow-up to show that results are consistent over time.
The temperature of the water was the most influential factor on the thickness of the carotid artery, showing tha heat therapy has a positive and lasting effect on the heart as well as hemodynamics.
Sauna Exposure Improves Arterial Compliance
European researchers published more details on their ongoing investigation into the effects of a single sauna session on cardiovascular function.
In this research article, they explored a more in-depth analysis of the effects of sauna bathing on the dynamics of blood flow and pressure as well as arterial compliance (20).
This experimental non-randomized study included 102 participants with a median age of 52.
They each had at least one cardiovascular risk factor.
Each subject had a 30-minute sauna session at a temperature of 73 degrees Celsius and a humidity level of 10 to 20 percent.
Measures of pulse wave velocity mean arterial pressure, pulse pressure, augmentation index, heart rate, blood pressure, augmented pressure, and left ventricular ejection time were collected before and after the sauna as well as 30 minutes later.
Results showed reductions in pulse wave velocity, blood pressure, mean arterial pressure, and left ventricular ejection time.
Decreases in blood pressure remained consistent during the recovery period.
Researchers concluded that systolic blood pressure, diastolic blood pressure, pulse wave velocity, mean arterial pressure, left ventricular ejection time, and diastolic time decreased immediately after using the sauna.
The decreases in both systolic BP and left ventricular ejection were sustained over time, showing long-term benefits.
Heat Therapy Improves Heart Function in Those with Limited Mobility
Researchers in Oregon wanted to explore the effects of passive heat therapy on the heart health of those with limited mobility or who are sedentary.
In their 2016 journal article, they investigated the effects of eight weeks of heat therapy on various biomarkers of cardiovascular health (21).
Subjects were twenty young adults with sedentary lifestyles.
They were divided into two groups.
The treatment group received heat therapy in the form of hot-water (40.5° C) baths for one hour four to five times per week).
The other half was assigned to a control treatment of thermoneutral water immersion.
The results showed that eight weeks of heat therapy increased flow-mediated dilation as well as superficial femoral dynamic compliance while reducing aortic pulse wave velocity.
In addition, carotid thickness and mean arterial blood pressure were reduced.
These results contrasted sharply with control subjects, who saw no changes in these areas.
Researchers concluded that heat therapy successfully increases flow‐mediated dilatation, reduces arterial stiffness, and mean arterial and diastolic blood pressure while also reducing carotid intima-media thickness, which are all indicators of improving cardiovascular health.
Results like these are generally attained through exercise therapy.
The results suggest that heat therapy could provide effective treatment for improving heart health in various populations, including people with limited exercise tolerance or who many have mobility issues.
Research into Sauna Use Reveals Growing Support for Its Use
In 2016, researchers in Ontario undertook a review of the literature to determine the mechanisms by which heat therapy improves cardiovascular health and if it should be considered a viable option for treating significant health problems (22).
Their reason for exploring this topic was because of the health crisis that cardiovascular disease poses to our population, as it is currently the leading cause of death in developed nations.
The use of thermal therapy as a treatment option has gained notoriety in the literature across the past several years.
Sauna bathing is among the most popular heat therapy investigated.
Numerous studies have demonstrated its effectiveness at improving cardiovascular health and yet the mechanisms of action are less understood.
One study the explored suggested that the alleviation of arterial stiffness could lead to the documented improvement in cardiac function.
Even brief, initial treatment can result in significant improvement in function, according to researchers.
Heat therapy should be considered to be a relevant and appropriate therapy for those with cardiovascular problems.
The review included an investigation of other outcome measures.
One such noteworthy finding was that heat therapy can lead to a decrease in carotid wall thickness, possible due to a breakdown of atherosclerotic plaque.
This finding requires more clinical study to understand fully.
Because heat therapy is also known to reduce blood pressure, it should be considered to be a treatment option for those with hypertension.
These authors suggestion routes for further exploration, including how arterial wall thickness is reduced and how heat therapy could be used as a preventative as well as a treatment option for cardiovascular disease.
The effects of heat therapy on the long-term health of those without cardiovascular disease is also an important question to explore.
The impact of long-term lowering of blood pressure on arterial strain is also suggested for future study.
The effects of heat therapy on certain conditions, including aortic stenosis, unstable angina, severe orthostatic hypotension, and pregnancy are also unknown at this time.
Older research points to diminishing results from heat therapy in older patients and this phenomenon should be studied in greater depth, as well.
These authors note that we have learned a lot about the effects of sauna use on heart health, but we have much more to learn still.
Exposure to High Temperatures Safe for Those with Hypertension
The authors of this 2003 research study wanted to explore the validity of warning for hypertensive patients to avoid hot tub use (23).
While this is a common suggestion, there is little evidence to support the necessity of such a claim.
This study compared heart rate, blood pressure, and other symptoms for people who say in a hot tub for ten minutes.
Subjects included those being treated for high blood pressure and those with healthy BP levels without treatment.
Participants were 21 patients with stable, well-managed hypertension, and 23 control subjects without high blood pressure.
Before their hot tub session, measures of blood pressure and heart rate were obtained as a baseline, and these measurements were repeated during and after a 10-minute session in a hot tub at 40 degrees Celsius.
Subjects were also asked to report any symptoms.
There were no reports of chest pain, palpitations, or dizziness from any of the subjects.
Both groups experienced a drop in systolic blood pressure during immersion.
This returned to baseline after 10 minutes outside the hot tub.
There was also a decrease in diastolic pressure and increases in heart rate across both groups.
The group with hypertension has slightly lower increases in heart rate.
The results of this study indicate that heat therapy, in this case, using a hot tub, should be considered safe for those with well-treated hypertension.
While blood pressure dropped for this group, it also did for those without hypertension, showing there is no increased risk, regardless of your hypertensive status.
Therefore, heat therapy, including sauna use, should be considered safe for most people with treated high blood pressure.
Heat Therapy Can Improve Diastolic Dysfunction
Researchers from the University of Colorado used animal trial data to consider the implications for humans using heat therapy to improve diastolic blood pressure (24).
An aging population means that our society faces a higher risk of developing cardiovascular disease.
Diastolic dysfunction is a leading cause of heart failure, a type of cardiovascular disease.
There are currently no established treatment options for improving diastolic function, which is a symptom associated with aging.
The authors review a rat study that investigated the effects of exercise training on both young and old subjects.
The more sedentary you are as you age, they concluded, the more likely you are to have diastolic dysfunction to some degree.
But dysfunction will set in as you get older, regardless of activity level, which is why it is essential to mitigate this through exercise as much as possible.
Animal trials show that even late-life exercise implementation helps improve blood flow and cardiac function.
In other words, you are never too old to start moving more.
While these results indicate the importance of exercise, the authors also wanted to explore the application of heat therapy in reducing diastolic dysfunction, since many in heart failure experience difficulties with exercise tolerance.
As such, the use of passive heat therapy using a sauna or hot baths was investigated.
Increases in core body temperature can activate, repair, and stabilize other proteins that are involved in cardiovascular function.
Heat therapy also improves blood flow, which can help with heart function.
In their review, the authors noted research to indicate that heat therapy, including sauna use, improves arterial stiffness and endothelial function while also lowering the risk of cardiac events, reentry into hospitals, and death.
Heat therapy can improve exercise tolerance, too.
These results show that this form of treatment could help improve cardiac function in those who are aging while resistant diastolic dysfunction.
Repeated Sauna Use Improves Ventricular Arrhythmias
Patients with chronic heart failure are at an increased risk for cardiac arrhythmias or irregular heartbeat.
Decreasing ventricular arrhythmias is a vital treatment focus for patients with heart failure, and heat therapy has been proposed as one way to improve this symptom.
Researchers from Japan sought to explore the use of sauna treatment on this condition to determine its effects in 2004 (25).
Thirty participants were recruited for this study. Each was Class II or Class III on the New York Heart Associations scale for chronic heart failure.
Each had at least 200 premature ventricular contractions (PVCs) per day.
The patients were divided into two groups. 20 received the sauna treatment, and ten were not treated.
The sauna treatment group participated in daily saunas for two weeks.
Each session lasted 15 minutes at 60 degrees Celsius in a far-infrared sauna.
There was then a 30-minute period of rest. Sessions were held five days per week.
The control group had bed rest for 45 minutes at room temperature.
Patients in the treatment group had a reduction in PVCs compared to the control group.
Heart rate variability increased while plasma brain natriuretic peptide concentrations decreased in the treatment group, as well.
These results show that patients with PVCs could experience fewer symptoms using regular sauna treatment, which is helpful for those with chronic heart failure.
Repeated Sauna Therapy Improves Vascular Endothelial Function
Japanese researchers in 2002 wanted to explore the effects of repeated sauna sessions on artery diameter as well as other measures of endothelial function to discern the effectiveness of sauna as a treatment tool for heart patients (26).
Their purpose was to determine how exactly sauna treatment improves cardiac function in patients with chronic heart failure.
Using previous research, the authors concluded that sauna treatment improves hemodynamics as well as clinical symptoms for those with CHF.
Their hypothesis was that this was due to a restoration of endothelial function.
The treatment group consisted of 20 patients who were either Class II or Class III for chronic heart failure.
They were each treated in a dry sauna for 15 minutes at 60 degrees Celsius then made to rest on a bed under a blanket for 30 minutes.
This occurred daily for two weeks.
The control group was ten patients with chronic heart failure who rested on a bed at room temperature for 45 minutes.
An ultrasound was used to measure the diameter of the brachial artery at ready as well as during the sauna session.
Patients were also given sublingual nitroglycerin, and then measurements were taken to compare.
Measurements of plasma brain natriuretic peptide concentrations were taken to determine cardiac function, as well.
In 17 of the 20 treatment patients, clinical symptoms improved after two weeks of sauna treatment.
The percent flow-mediated dilation significantly increased with sauna treatment but not with nitroglycerin-induced dilation.
After two weeks of sauna treatment, concentrations of brain natriuretic peptide were much lower, and these changes all correlated to each other.
No changes were noted in the control group.
The researchers concluded that repeated sauna treatments improved the vascular endothelial function of these patients with chronic heart failure, resulting in improved cardiac function and clinical symptoms.
Far-Infrared Saunas Are Safe for Those with Heart Failure
Waon therapy is a combination of dry sauna warming with bed rest after heat therapy.
It originated in South Korea and generally uses a far-infrared sauna instead of a traditional Finnish sauna.
In 2010, researchers in South Korea wanted to examine the effects of this type of therapy on patients with heart failure (27).
The safety of any therapy on those with chronic heart failure is always a concern.
Researches in Korea wanted to assess the effects as well as the safety of Waon therapy.
They selected two patients with chronic heart failure.
They say in an infrared sauna heated to 60 degrees Celsius for 15 minutes, then rested on a bed under a black for an additional 30 minutes.
This happened once w day for five days per week for two weeks.
Four of the five patients noted improvements in their symptoms and had a decrease in left ventricular volume.
There were slight improvements in left ventricular ejection fraction and diastolic function after therapy.
There were no adverse effects noted.
Blood pressure decreased after treatment, but the heart rate remained unchanged following therapy sessions.
The researchers concluded that Waon therapy is safe and well-tolerated for those with chronic heart failure and may also have some benefits for this condition.
They found that this form of treatment could hold promise for treating heart failure.
Sauna use is proven to improve heart function and help you live longer.
The use of heat therapy has been shown time and again to improve your heart’s ability to provide life-giving oxygen and nutrients to your body.
Heating your body though sauna bathing helps improve circulation, lower blood pressure, reduce the thickness of arteries, and improve cardiac function and output.
Even patients with chronic heart failure or other conditions can see improvements when using regular sauna bathing.
As we have covered extensively in this report, sauna use influences your heart in many positive ways.
Those who are healthy and those with heart problems will benefit from regular sauna sessions, including enjoying a longer life.
Heat stress therapy can help your heart as well as your health in many other ways.
We know that sauna bathing is associated with strong muscles, more endurance, improved blood sugar levels, less pain, and lower levels of inflammation.
Most people tolerate sauna use well and if can be a terrific addition to your wellness practices, regardless of your age and mobility.
There are minor risks, but these are much fewer than conventional recommendations would lead you to believe.
Try using a sauna today to improve your heart health, and soon you will see the difference for yourself.