How often do you take a bath? We’re willing to guess that it’s rare. Baths feel like a huge indulgence given the amount of time and water they require. Now, however, you may have a better excuse for relaxing in the tub: There’s evidence that taking a bath on a regular basis can reduce your risk of heart disease.
A study published in the journal Heart found that taking a bath on a daily basis reduces the risk of heart disease by 28 percent and the risk of a stroke by 26 percent. Frequent baths were also associated with lower blood pressure and a reduced risk for type 2 diabetes.
A 2010 study published in Complementary Therapies in Clinical Practice had already established some of the benefits of frequent bathing. Specifically, the volunteers in the experiment reported better sleep quality and better self-rated health. The Heart study expanded on this research with a much larger investigation that focused on the long-term effects of tub bathing.
Dipping into the Research
Over the course of 19 years from 1990 to 2009, researchers in Japan studied the health and bathing habits of 30,076 participants. The volunteers were between 40 and 59 years of age and they had no history of cardiovascular disease (CVD) or cancer.
After reporting their bathing habits to the researchers, participants were split into three groups: those who bathed zero to two times per week, those who bathed three to four times per week, and those who bathed every day or almost every day.
The scientists followed up with the participants frequently and ultimately recorded 2,097 incidences of heart disease. In analyzing the data, they made sure to account for other influential factors, such as weight, diet, smoking status, exercise regimens, alcohol intake, job status, education, sleeping habits, and overall happiness.
Once they adjusted their findings for these factors, researchers discovered that patients who bathed more frequently were less likely to develop CVD. They were less likely to suffer from strokes as well.
People who bathed more also had lower diastolic blood pressure (the bottom number) and lower levels of glycated hemoglobin. Glycated hemoglobin is a substance in red blood cells that can attach to sugar in the blood, and higher levels of this molecule are a key risk factor for type 2 diabetes.
The temperature of the bathing water also made a difference. Hot water was linked to a 35 percent reduced risk of heart disease, while warm water was linked to a 26 percent reduced risk.
The Scientific Benefits of Bathing
Why might bathing improve the health of your heart? As explained in the publication, being submerged in hot water can boost hemodynamic function, which is a general measurement of how efficiently blood gets pumped through the body.
Having good hemodynamic function is an indication of low blood pressure. Poor hemodynamic function, on the other hand, means you have either extremely high or extremely low blood pressure and your heart has to work harder.
Investigators in the study also stated that heat exposure can increase core body temperature, boost the heart rate, and ramp up circulation, almost like cardiovascular exercise. Over the long term, routine heat exposure may strengthen the heart, decrease stress on blood vessels, and improve overall vascular function.
Other Facts to Keep in Mind
As with any scientific study, the findings from this one came with a few caveats. First, the researchers pointed out that tub bathing can cause heatstroke more frequently if the temperature of the water is too high. (If you’re wondering about the optimal water temperature, investigators say it’s about 107.6 degrees Fahrenheit, while the Cleveland Clinic believes it’s around 112 degrees.)
Researchers pointed out that participants who took more baths were also more likely to lead healthy lifestyles. Thus, the causal effect between bathing and a lower risk of heart disease could be questionable.
American culture is also vastly different from Japanese culture. U.S. adults are far more likely to suffer from obesity and a variety of illnesses linked to being overweight. As a result, American adults may not see the same benefits of frequent bathing as Japanese adults.
Still, you might discover some great benefits of taking baths more regularly. Whether you call it therapy, relaxation, or simply “me time,” that hot water could help improve your circulation and ease your daily stress.