The Science of Cryotherapy

This cold exposure causes a rapid drop in skin and superficial tissue temperature, triggering temporary constricting of the blood vessels, reducing local blood flow and limiting the spread of inflammatory substances. As the body rewarms, the subsequent dilation of blood vessels may help clear metabolic waste and inflammatory compounds called cytokines.

On a molecular level, cryotherapy appears to influence immune function by lowering inflammatory markers and activating genes linked to antioxidant defense (for example, the SOD2, SIRT1, and SIRT3 genes). It also causes an initial surge in sympathetic nervous system activity, followed by a shift toward a calming, parasympathetic response—the feeling you get from meditation, deep breathing, or spending time in nature. Changes occur in brain chemicals like norepinephrine and possibly brain-derived neurotrophic factor, which may contribute to mood improvements and pain relief.

Current evidence suggests cryotherapy works through multiple physiological pathways—affecting blood vessels, immune function, antioxidant systems, and the nervous system—resulting in short-term reductions in inflammation, oxidative stress, and pain.

The potential benefits

• Pain and chronic inflammatory conditions: Whole-body cryotherapy consistently reduces inflammatory markers while increasing anti-inflammatory compounds. These effects have been documented across a range of groups, including athletes, people with obesity, and people with chronic inflammatory conditions such as rheumatoid arthritis. Reductions in pain, disease activity, and inflammatory markers have also been seen in people with chronic low back pain, fibromyalgia, multiple sclerosis, and chronic fatigue syndrome.
  • Cryotherapy is well-tolerated and can reduce the use of painkillers, improve quality of life, and decrease fatigue, but improvements are generally modest and not maintained long-term. There is no evidence that cryotherapy alters the underlying disease process in these conditions.
  • The anti-inflammatory response is typically most pronounced within 24 to 48 hours after a session, and with regular use—commonly five sessions per week for two to four weeks—benefits may persist for up to two weeks. However, after you stop, both inflammatory markers and clinical symptoms generally return to where they were before.

• Muscle soreness and exercise recovery: Numerous clinical trials demonstrate that cryotherapy decreases muscle soreness and perceived fatigue after exercise. However, objective measures of exercise recovery—such as muscle strength, power output, and sprint speed—are not improved. The literature consistently shows that while pain and subjective recovery are enhanced, actual restoration of muscle function and performance is not accelerated. Thus, cryotherapy primarily provides symptomatic relief rather than true enhancement of recovery.

• Cognitive decline, depression, and anxiety: Early data suggest a potential modest improvement in memory, orientation, mood, and well-being in those with mild cognitive impairment, but more data is needed. Preliminary data also demonstrate short-term benefits for those with depression, especially when combined with medication. Improvements in anxiety disorders may occur in some people, but the data is less consistent. Effects, as noted earlier, appear to be short term.

• General mood, well-being, and stress: In individuals without a mood disorder, cryotherapy may yield small improvements in general mood and well-being, but the greatest effects are generally more pronounced in those with lower baseline mental health. Cryotherapy does not appear to improve resilience to everyday stressors.

• Weight loss and brown adipose tissue (BAT): It's well established that whole-body cryotherapy can activate brown adipose tissue—calorie-burning fat cells that generate heat. The mechanism involves stimulation of the sympathetic nervous system and increased production of UCP1, a protein that facilitates heat generation from stored energy. Repeated cold exposure can gradually enhance brown fat volume and heat-generating activity, improving cold tolerance and potentially resulting in modest weight loss—typically around 2 to 4 pounds after approximately 20 sessions.
  • However, almost all studies demonstrating this effect are short-term, lasting only 2 to 4 weeks. The only study that looked at a longer period of six months combined moderate aerobic exercise with 40 sessions of cryotherapy and found no lasting changes in body weight or fat mass attributable to the cold treatment. These findings suggest that while brown fat activation is real, it doesn't result in sustained or clinically meaningful amounts of weight loss.

• Immune function: Whole-body cryotherapy appears to reduce inflammation throughout the body as previously discussed, and may affect immune function. However, the impact of this is still not clear and there is no data that this “boosts” the immune system or reduces illness, as is often claimed in marketing materials for cryotherapy.

What to know before you try it

If you intend to do cryotherapy, here is what you should know:

• Sessions should last 2–3 minutes each
• To get the benefit, it’s recommended you do it 5 times per week, generally for at least 2-4 weeks
• You must wear protective gear, such as gloves and socks, to protect your extremities
• Avoid cryotherapy after resistance training; repeated use of whole-body cryotherapy or other cold modalities after resistance training may blunt muscle growth, likely because cold therapy dampens the mild inflammation that signals your body to build new muscle tissue.
• People who are pregnant, children, and those with cardiovascular disease, unmanaged high blood pressure, cold-sensitivity disorders, Raynaud’s syndrome, impaired circulation, severe respiratory disorders, deep vein thrombosis, certain neurological disorders, open wounds, metal implants, or pacemakers should avoid cryo unless advised otherwise by a health care professional. Rare side effects include cold burns, dizziness, and—very rarely—fainting due to vasoconstriction.
• Always talk to your doctor before starting cryotherapy, especially if you have underlying health conditions or take medication that affects circulation or blood pressure.

Staying safe

Cryotherapy typically takes place in a specially designed chamber at a wellness clinic, sports facility, or rehabilitation center. The cryotherapy chambers themselves are all quite similar, but the level of safety and oversight at each facility can vary widely. Look for centers that employ medical professionals who go through a standard medical intake and screening process to safely select candidates for the therapy.

There are a few at-home cryotherapy chambers on the market, but we do not recommend them due to safety concerns.

The bottom line:

The benefits of whole-body cryotherapy are primarily symptomatic, offering short-term relief without affecting the underlying disease process. Once treatment stops, so do the effects. As such, it’s important to weigh these temporary benefits against the opportunity cost, considering whether your time and money might be better invested in something with a more meaningful and lasting impact.