Heat is one of the oldest comfort measures for stiff joints, from warm baths to heating pads. An infrared cabin is a bigger version of the same idea, so it’s reasonable to ask whether it does more.
This page covers the trials that tested infrared saunas for arthritis and fibromyalgia. It is general information, not medical advice. For infrared research in general, see the overview of infrared sauna benefits.
Short answer: in a 2009 pilot study of 34 people with rheumatoid arthritis or ankylosing spondylitis, pain and stiffness fell significantly during infrared sessions, with no flare-ups. Over 4 weeks, the gains were not statistically significant. A 2008 study of 13 women with fibromyalgia reported pain halving after one session, without a control group.
Rheumatoid arthritis and ankylosing spondylitis
Oosterveld (2009) gave 17 people with rheumatoid arthritis and 17 with ankylosing spondylitis 8 infrared sauna sessions over 4 weeks, in Clinical Rheumatology.
| Measure | Result |
|---|---|
| Pain and stiffness during a session | Fell significantly in both groups |
| Fatigue | Also decreased |
| Pain, stiffness, fatigue over 4 weeks | Improved, not statistically significant |
| Disease activity scores | No relevant change (no flare) |
| Adverse effects | None reported |
The authors concluded:
“Infrared treatment has statistically significant short-term beneficial effects and clinically relevant period effects during treatment in RA and AS patients without enhancing disease activity.”
Oosterveld FG et al., Clinical Rheumatology, 2009
Fibromyalgia
Matsushita (2008) treated 13 women with fibromyalgia using Waon therapy, in Internal Medicine. Each session was 15 minutes in a far-infrared sauna at 60°C (140°F), then 30 minutes resting under a blanket, given 2 to 5 days a week.
All 13 reported less pain after the first session, by 11 to 70%, about half on average. After 10 sessions, the reduction held at 20 to 78%.
A related 2015 study from the same group, in 10 people with chronic fatigue syndrome, found less fatigue after 4 weeks of Waon therapy but no change in pain.
What Cleveland Clinic says
Cleveland Clinic says some research suggests infrared sauna therapy “might help relieve certain types of chronic pain.” It lists pain relief as one of six possible benefits, not a proven one.
Limitations
The arthritis pilot had 34 people, and its abstract reports no control group. The fibromyalgia study had 13 and no control group. Pain was self-reported in both. Neither abstract reports follow-up after treatment ended.
Here’s what the spec sheet won’t tell you. No trial here tested a home cabin; the Japanese study used a hospital-run protocol at a set 60°C.
My rule of thumb: treat infrared heat as a comfort measure that may ease stiffness for a while, not as a treatment that changes the disease.
Bottom line: small, uncontrolled studies show short-term pain relief in arthritis and fibromyalgia without flare-ups, but no lasting effect has been shown. For the wider infrared evidence, see the benefits overview linked above.
Sources
- Oosterveld FG et al., “Infrared sauna in patients with rheumatoid arthritis and ankylosing spondylitis. A pilot study showing good tolerance, short-term improvement of pain and stiffness, and a trend towards long-term beneficial effects,” Clinical Rheumatology, 2009;28:29-34 (abstract): pubmed.ncbi.nlm.nih.gov
- Matsushita K, Masuda A, Tei C, “Efficacy of Waon therapy for fibromyalgia,” Internal Medicine, 2008;47:1473-1476 (abstract): pubmed.ncbi.nlm.nih.gov
- Soejima Y et al., “Effects of Waon therapy on chronic fatigue syndrome: a pilot study,” Internal Medicine, 2015;54:333-338 (abstract): pubmed.ncbi.nlm.nih.gov
- Cleveland Clinic, “6 Possible Benefits of Infrared Saunas,” October 9, 2026: health.clevelandclinic.org