A scientific study from Japan has suggested that heart-healthminded individuals can ditch their gym membership and get in the hot tub instead.

A study coming out of the Osaka University Graduate School of Medicine has shown that that frequent hot tub bathing reduces the risk of cardiovascular disease among the middle aged.

The study was published in the March 2020 edition of Heart, an international peer-reviewed scientific journal for cardiologists.

According to the study, the more frequent the bathing, the better it seems to be for cardiovascular health, with a daily hot bath more defensive against cardiovascular disease than once or twice weekly soakings, researchers reported.

Specifically, compared with people who didn't take a tub bath more than twice a week, people who took a daily warm or hot bath had a 28% lower risk of cardiovascular disease and a 26% lower risk of stroke.

Further, the evidence suggests that the hotter the water the better — with a 26% lower risk of CVD in warm water compared to 35% lower risk in hot water. That said, it should be noted that immersion in hot water is also associated with sudden death, particularly in the elderly, either by accidental drowning or heart attack triggered by a rapid change in body temperature, or by heatstroke.

To arrive at these conclusions, researchers analyzed the self-reported health and lifestyle information from more than 30,000 middle-aged (45 to 59 years) people in Japan.

At the beginning of the study in 1990, some 43,000 participants responded to a questionnaire at the beginning of the study and were then followed for about 20 years.

The questionnaire consisted of questions concerning bathing habits as well as other potentially influential factors such as: lifestyle, to include exercise, diet, alcohol intake, smoking habits, weight (BMI); average sleep duration, and medical history and current medicines use.

Each participant was monitored until completion of the study in December 2009 or death, whichever came first. The final analysis was based on 30,076 people.

During this time frame, 2097 cases of cardiovascular disease occurred: 275 heart attacks; 53 sudden cardiac deaths; and 1769 strokes. Researchers found that the incidence of cardiovascular disease and stroke for those who took daily baths was statistically lower than for those who bathed once or twice a week.

The researchers further noted that the typical style of Japanese bathing involves immersion to shoulder height, which may be a critical factor.

Also, they pointed to previously published research, which has linked heat exposure to cardiovascular disease prevention – there, it was said that the effects of heat exposure are not dissimilar to that of exercise.

“We found that frequent tub bathing was associated with a lower risk of hypertension, suggesting that a beneficial effect of tub bathing on risk of [cardiovascular disease] may in part be due to a reduced risk of developing hypertension,” the researchers wrote.

It is important to note that the study is only observational and doesn't prove that daily tub bathing prevents heart problems – rather, there is a correlation.