Cryotherapy exposes the body to ultra-low temperatures, typically between -110°C and -140°C, for a short duration, usually two to four minutes. This method is performed in specialized chambers using liquid nitrogen vapor or refrigerated air. Initially developed for medical purposes, such as reducing inflammation and muscle soreness, the practice has gained public attention for its potential to stimulate metabolism. The core consumer claim is that this brief, intense cold exposure forces the body to burn a significant number of calories, promoting weight reduction.
The Core Mechanism: Cold Exposure and Metabolism
The theoretical link between cryotherapy and weight management lies in the body’s natural response to extreme cold, a process called thermogenesis. Thermogenesis is the physiological production of heat, which the body uses to maintain its core temperature of about 37°C when external temperatures drop. This heat generation requires energy, which is supplied by burning stored fuel, specifically glucose and fat.
A major contributor to this cold-induced energy expenditure is Brown Adipose Tissue (BAT), often referred to as brown fat. Unlike white fat, which stores energy, BAT is metabolically active and contains a high density of mitochondria, specialized cellular structures. When cold stress occurs, the sympathetic nervous system triggers the release of norepinephrine, activating BAT.
This activation causes the mitochondria within the brown fat cells to uncouple the process of energy production from the generation of adenosine triphosphate (ATP), instead releasing the energy directly as heat. This non-shivering thermogenesis effectively turns BAT into a furnace that burns calories to keep the body warm. Proponents suggest that cryotherapy stimulates or increases the amount of metabolically active brown fat, a process known as “browning,” leading to a sustained increase in resting metabolic rate.
Types of Cryotherapy and Caloric Expenditure
Cryotherapy is administered in two main forms: Whole-Body Cryotherapy (WBC) and localized cryotherapy. Localized treatments focus a cold stream on specific body parts, primarily for pain relief and inflammation reduction, and are not intended for systemic weight loss. Whole-Body Cryotherapy, which involves standing in a cryochamber, is the method marketed for metabolic benefits.
The immediate caloric expenditure during a typical three-minute WBC session is relatively minor compared to physical exercise. While some commercial entities claim a burn of up to 800 calories per session, scientific measurements suggest the actual energy cost is more modest. The direct calorie burn during the session and the immediate post-session period is often estimated to be around 50 to 150 calories.
This energy expenditure is primarily due to the body’s attempt to restore thermal balance, sometimes referred to as the afterburn effect. However, a single, short session’s calorie deficit is easily negated by subsequent food intake. One study involving male athletes observed that exposure to Whole-Body Cryotherapy increased their subsequent energy intake by a significant amount, suggesting the cold exposure may stimulate appetite following the session.
Scientific Findings on Sustained Weight Reduction
Research into cryotherapy’s effect on long-term weight reduction, specifically the sustained decrease in body mass index (BMI) and body fat percentage, presents mixed results. The most robust scientific evidence is concentrated on the metabolic effects, not on significant, lasting weight loss as a standalone treatment. Studies have consistently demonstrated that repeated cold exposure activates thermogenesis, but this does not automatically translate into a substantial loss of body weight.
Some limited clinical research has shown promising, though not definitive, results in specific populations. For instance, a study focusing on menopausal women with metabolic syndrome found that multiple Whole-Body Cryotherapy sessions were associated with a reduction in abdominal obesity. Another investigation into regular, long-term cryotherapy treatments reported a small but measurable average reduction in body mass and waist circumference, suggesting a localized fat-reducing effect linked to cold-induced thermogenesis.
Despite these findings, the scientific consensus is that cryotherapy alone is not a sufficient method for achieving significant, sustained weight loss comparable to diet and exercise. The current body of evidence is limited by small sample sizes, short study durations, and a lack of high-quality, randomized controlled trials. Therefore, cryotherapy is best viewed as a potential complementary therapy that may improve metabolic markers, but it is not a primary solution for obesity.
Practical Considerations and Regulatory Status
Individuals considering Whole-Body Cryotherapy for weight management should be aware of important safety and regulatory factors. Potential acute side effects include skin burns, frostbite, and numbness due to the extreme temperatures, particularly if moisture is present or protective gear is not worn correctly. A more severe risk, especially in cryosaunas that use liquid nitrogen, is the potential for oxygen displacement, which can lead to hypoxia or asphyxiation if the gas escapes into the chamber.
The cost of cryotherapy is also a practical consideration, with individual sessions often ranging from $35 to $65 or more, making long-term, repeated use expensive. Crucially, the devices used for Whole-Body Cryotherapy have not been cleared or approved by the U.S. Food and Drug Administration (FDA) for the treatment of any specific medical condition. The FDA has issued warnings stating there is insufficient evidence to support the claims of safety and effectiveness for conditions such as weight loss. Consumers should understand that cryotherapy is not a regulated medical treatment and should not be used as a substitute for established weight loss strategies, such as a balanced diet and consistent physical activity.