Why do my joints ache in the cold?
Can the warmth of a hot bath or steam sauna help?
Brrr! It’s unusually cold in the South this week! We’ve had snow, and schools have been canceled for the past three days due to unsafe road conditions. Born and raised in southwest Florida, I’ve always preferred a sweltering day at the beach over wintry weather. As I’ve gotten older, I’ve found yet another reason to avoid the cold: my aching joints!
I’ve been diagnosed with osteoarthritis in my right hip. At the age of 45, I was told I had the hip of a 70-year-old. This is the same hip that underwent two surgeries during my teenage years to correct hip dysplasia, and it has never functioned like a normal hip joint. Interestingly, my hip pain seems to flare up most on cold, wet days. But why does this happen?
Well, some scientists investigated this exact question. A large European study investigating the influence of weather on joint pain examined 810 older adults with osteoarthritis in their knees, hands, and/or hips. The key findings from the study revealed:
There is a significant interaction between daily average humidity and temperature on joint pain.
The effect of humidity on pain is stronger in colder weather conditions.
In simple terms: cold, humid weather (like snowy or sleety conditions) is linked to increased joint pain in this group. So, I’m certainly not alone in experiencing this phenomenon!
Easing the Pain
If cold, humid conditions exacerbate arthritic pain, could wet heat offer relief? In the face of this weather and my joint pain, my body has craved heat—both externally and internally. I’ve found comfort in sipping cozy cups of hot herbal tea and easing my aches with soaks in hot baths or sessions in steam saunas. From a completely anecdotal perspective, these remedies have definitely helped! But what does the science say? Unfortunately, the answer isn’t entirely clear.
It is well known that heat exposure, such as from a hot bath or steam room, can increase blood flow to the joints due to the vasodilatory effects of heat. This enhanced circulation delivers oxygen and nutrients to the affected area, which may help reduce localized inflammation.
When it comes to muscular pain and recovery from sports injuries, research into passive heat exposure (through hot baths, saunas, or other heat sources) has found that it:
Improves both voluntary and involuntary muscle responses.
Enables muscles to react faster and generate peak force more quickly.
Helps muscles relax faster and respond more efficiently to nerve signals.
While there have been numerous studies examining the effects of sauna use on cardiovascular health and even neurocognitive diseases (this review provides a good overview), I was unable to locate any clinical trials specifically focused on sauna use for osteoarthritis. However, I did find one small study involving 41 female patients with knee osteoarthritis who were treated with a heat/steam-generating sheet for four weeks. The study found significant improvements in clinical symptoms compared to treatment with heat alone (without steam).
Interestingly, traditional sauna practices—such as those common in Finland and other northern European regions—often involve cycles of heat exposure followed by cold immersion or rest at room temperature. This thermal cycling strategy also requires additional study.
As with any form of traditional medicine, the "dose" and length of exposure matter. It’s important to use heat therapies safely: never stay in the heat to the point of feeling faint, avoid combining heat treatments with drugs or alcohol, and consult a physician before use if you are pregnant.
The Takeaway
I’d love to see more research in this area. Gaining a deeper understanding of the risks, benefits, and potential efficacy of hot baths or saunas for arthritis patients could be a great step forward. Such studies would provide valuable insights into noninvasive, non-pharmaceutical options for pain management, offering patients alternative ways to improve their quality of life.
Yours in health, Dr. Quave
Cassandra L. Quave, Ph.D. is a Guggenheim Fellow, CNN Champion for Change, Fellow of the National Academy of Inventors, recipient of The National Academies Award for Excellence in Science Communication, and award-winning author of The Plant Hunter. Her day job is as professor and herbarium curator at Emory University School of Medicine, where she leads a group of research scientists studying medicinal plants to find new life-saving drugs from nature. She hosts the Foodie Pharmacology podcast and writes the Nature’s Pharmacy newsletter to share the science behind natural medicines. To support her effort, consider a paid or founding subscription to Nature’s Pharmacy or donation to her lab research.
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