Hot Tub Vs. Sauna: Which One Truly Benefits Your Health More?

Hot tubs and saunas have long been praised for their soothing warmth and muscle relaxation, but a new study suggests hot tubs might actually deliver greater health benefits than saunas. Researchers at the University of Oregon’s Bowerman Sports Science Center compared the effects of soaking in a hot tub to sitting in traditional dry saunas and far-infrared saunas. Their findings point to hot water immersion as a more powerful way to improve heart and immune health (1^✔ ✔Trusted Source
Comparison of thermoregulatory, cardiovascular, and immune responses to different passive heat therapy modalities

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Inside the Study

The study, published in the American Journal of Physiology, involved 20 young, healthy adults who regularly exercised, ranging in age from 20 to 28. Participants were exposed to three types of passive heat therapy: hot tubs, traditional saunas, and far-infrared saunas.

The researchers used advanced monitoring to measure body temperature, heart rate, blood pressure, cardiac output, and immune cell responses before, during, and after each session.

“We compared the most commonly used types of passive heating as they’re applied in everyday life,” explained lead author Jessica Atencio, a doctoral student at the Bowerman Center. “No studies had compared the acute responses between these three before.”

Key Findings

Hot water immersion raised core body temperature the most, which in turn triggered an increase in blood flow, lowering blood pressure, and stimulating immune cells. These effects were stronger than those seen with sauna use.

“Increasing body temperature causes an increase in blood flow, and just the force of blood moving across your vessels is beneficial for your vascular health,” Atencio noted.

Interestingly, the hot tub also caused a measurable inflammatory response, something researchers say could help boost the immune system, thanks to elevated immune signaling molecules and changes in immune cell patterns.

Why Hot Tubs Might Work Better

Hot tubs are more effective at raising and maintaining core body temperature because water prevents the body from cooling itself through sweat, Atencio explained. “When you’re submerged in water, the sweat mechanisms aren’t efficient,” she said.

Christopher Minson, senior author and professor of human physiology, emphasized that heat therapy can be a powerful health tool. “If people are willing to do some heat therapy, it’s going to align with improved health, as long as it’s done in moderation,” he said.

Heat therapies like hot tubs may serve as a supportive alternative for those unable or unwilling to exercise. “We always say that exercise is the primary non-drug treatment for promoting health, but heat therapy is good supplementation,” Atencio added.

A Safe Path Forward

While heat therapies have clear benefits, researchers caution people to be smart and safe about using them. Minson advises consulting a physician before beginning regular heat therapy, especially for people with underlying health conditions.

“It can be a very peaceful, sometimes religious, sometimes cultural, and sometimes social experience,” Minson said. “Those aspects contribute to the health benefits and are critically important.”

The takeaway? If you’re looking for a relaxing way to help your heart and immune system, a soak in the hot tub might offer more than just a pleasant pause; it could deliver measurable health perks beyond what a sauna can do.

Reference:

1. Comparison of thermoregulatory, cardiovascular, and immune responses to different passive heat therapy modalities - (https://journals.physiology.org/doi/full/10.1152/ajpregu.00012.2025)

Source-Medindia