For decades, traditional saunas have been a cornerstone of wellness culture in Scandinavia. But a newer generation of heat therapy — infrared saunas — is drawing serious attention from researchers, physicians, and biohackers alike. Here’s what the science actually says.
How Infrared Saunas Work
Unlike conventional saunas that heat the surrounding air to temperatures above 185°F, infrared saunas use near-, mid-, and far-infrared wavelengths to warm the body directly. This allows for a deeply penetrating heat at lower ambient temperatures (typically 120–150°F), which many users find more comfortable and sustainable for longer sessions.
The key mechanism: infrared energy is absorbed by the body’s tissues, raising core temperature and triggering a cascade of physiological responses similar to — and in some ways surpassing — what you’d get from moderate aerobic exercise.
What the Research Shows
Finnish epidemiologist Dr. Jari Laukkanen has published some of the most compelling data on sauna use. His landmark study of over 2,300 middle-aged Finnish men found that those who used a sauna 4–7 times per week had a 40% lower risk of all-cause mortality compared to once-a-week users. Cardiovascular mortality dropped even more dramatically.
While Laukkanen’s research used traditional saunas, subsequent studies have found that infrared sessions produce similar cardiovascular responses: reduced blood pressure, improved arterial compliance, and increased heart rate comparable to moderate exercise.
A 2018 review published in Evidence-Based Complementary and Alternative Medicine found infrared sauna therapy to be beneficial for chronic fatigue syndrome, while separate research points to improved outcomes for patients with congestive heart failure, chronic pain, and type 2 diabetes markers.
Beyond Cardiovascular Health
The benefits extend well beyond the heart. Regular infrared sauna sessions have been associated with:
- Detoxification: Sweat produced during infrared sessions has been shown to contain heavy metals, BPA, and other environmental toxins at higher concentrations than sweat from conventional exercise.
- Muscle recovery: Increased circulation and heat shock protein production accelerate repair of muscle micro-tears, making infrared saunas popular among athletes.
- Mental health: A 2016 study in JAMA Internal Medicine found whole-body hyperthermia reduced depressive symptoms significantly, with effects lasting up to six weeks.
- Skin health: Improved circulation and collagen stimulation support skin elasticity and tone with regular use.
Full-Spectrum vs. Far-Infrared
Not all infrared saunas are created equal. Full-spectrum models emit near-, mid-, and far-infrared wavelengths, each with distinct penetration depths and therapeutic targets. Near-infrared penetrates most superficially, supporting skin and wound healing. Far-infrared reaches deepest — the wavelength responsible for most cardiovascular and detoxification benefits.
Brands like Peak Saunas have pushed this further, building full-spectrum cabins with medical-grade red light therapy panels integrated alongside traditional heaters, so users capture both the thermal and photobiomodulation benefits in a single session.
Getting Started
For those new to infrared therapy, researchers generally recommend starting with 15–20 minute sessions at lower temperatures and building toward 30–45 minutes, 3–4 times per week. Hydration before and after is essential, as is allowing the body time to cool naturally post-session.
The 4x-per-week threshold appears to be where the most pronounced health benefits emerge — consistent with Laukkanen’s frequency data and increasingly cited by integrative medicine practitioners.
The Bottom Line
Infrared sauna therapy has moved well beyond wellness trend territory. With a growing body of peer-reviewed research, credible mechanisms of action, and an improving hardware ecosystem, it’s earning its place as a legitimate tool in preventive health — one that’s accessible enough to build into a daily or near-daily routine.