This odd couple could be the next gut health breakthrough
Industry Buzz
Although the sample size is small, our findings suggest that combining two accessible lifestyle interventions—yogurt intake and onsen bathing—may offer enhanced health benefits, particularly by promoting gut microbiota diversity and improving defecation status in healthy adults.
—Shunsuke Managi, director of the Urban Institute at Kyushu University
New research out of Japan is shining a spotlight on a duo you might not expect to see in the same sentence: eating yogurt and hot spring bathing.
According to the study, published in Frontiers in Nutrition in June 2025, combining regular yogurt intake with frequent hot spring baths could synergistically improve gut health, enhancing the diversity and balance of intestinal microbiota. []
While both yogurt and hydrothermal bathing have been studied individually for their effects on digestion and microbiome composition, this study is among the first to look at their combined impact in healthy adults.
The researchers found that participants who bathed in chloride hot springs after eating yogurt had a more favorable gut microbial profile compared with those who practiced only one—or neither.
Related: Here’s how a healthy gut lets you live a longer, healthier lifeProbiotics meet relaxation
Yogurt has long been praised for its probiotic content, which can help support beneficial bacteria in the gut. But the study suggests that hot spring bathing may amplify these effects.
Thermal exposure seems to positively influence microbiome diversity, possibly through stress reduction and improved circulation, creating an environment in the gut where probiotic strains from yogurt can thrive.
The study followed a cohort of adults over several months, analyzing stool samples and lifestyle data. Those who combined daily yogurt consumption with hot spring visits exhibited increased abundance of beneficial bacteria like Bifidobacterium and Lactobacillus, alongside decreased markers associated with gut inflammation.
Why this matters for patients—and you
For physicians counseling patients on gut health, this study adds a layer of nuance. While diet remains the cornerstone of microbiome modulation, lifestyle interventions—including stress management and thermotherapy—may have measurable benefits when combined with dietary probiotics.
"Although the sample size is small, our findings suggest that combining two accessible lifestyle interventions—yogurt intake and onsen bathing—may offer enhanced health benefits, particularly by promoting gut microbiota diversity and improving defecation status in healthy adults. These results are especially relevant given the growing interest in non-pharmaceutical, lifestyle-based strategies for preventive health and wellness," said co-study author Shunsuke Managi. []
Related: The magic gut health pill your patients shouldn't be takingThe takeaway for doctors
Encourage patients to think beyond pills and supplements. For those already consuming probiotics, incorporating low-risk lifestyle habits—like warm baths, sauna sessions, or if available, hot spring bathing—may further support gut microbial diversity and overall digestive health.
The study was small and done only in men, so the results are not a replacement for evidence-based treatments for GI disorders. However, these adjunctive strategies could improve patient adherence and well-being.
Related: A gut sponge for microplastics? Kimchi-derived probiotic sparks interest