Cryotherapy: Using Cold Negative Temperatures for Positive outcomes

Cryotherapy is the therapeutic application of extreme cold for medical purposes, derived from the Greek words "cryo" meaning cold and "therapy" meaning cure. The practice encompasses a diverse range of techniques, from localized destruction of abnormal tissue to whole-body exposure for systemic effects. Historically, cold has been used for healing since the seventeenth century, but modern cryotherapy has evolved into a sophisticated medical intervention with applications across dermatology, oncology, sports medicine, and rehabilitation.

The term cryotherapy covers several distinct modalities. Cryosurgery, also called cryoablation, uses extreme cold to destroy unwanted tissue such as skin lesions, tumors, or precancerous cells. Whole-body cryotherapy involves brief exposure to severely cold air in specialized chambers, typically ranging from minus 90 to minus 160 degrees Celsius, for two to four minutes. Localized cryotherapy applies cold to specific body areas using devices such as ice packs, probes, or hyperbaric gaseous carbon dioxide. Intracanal cryotherapy is a dental application using cold saline irrigation during root canal procedures to reduce postoperative pain.

Despite the diversity of applications, all forms of cryotherapy share a common biophysical foundation: the controlled removal of heat from living tissue to achieve therapeutic goals including reduced inflammation, pain relief, vasoconstriction, and in more extreme applications, cellular destruction.

Technical Details and Important Information for Cryotherapy

1. Types of Cryotherapy and Temperature Parameters

Whole-Body Cryotherapy (WBC)

Whole-body cryotherapy involves exposure to extremely cold dry air in a temperature controlled chamber. A 2026 pilot study investigating the effects of repeated WBC used a protocol of minus 90 degrees Celsius for sessions lasting three to six minutes. Participants wore minimal clothing including shorts for males and shorts with a crop top for females, along with protective gloves, a woolen headband covering the ears, and a nose and mouth mask to prevent cold-related injury. Dry shoes and socks were also worn. The study administered 18 sessions over nine weeks, followed by a nine-week observation period.

Cryosurgery and Dermatologic Cryotherapy

Cryosurgery uses cryogens, most commonly liquid nitrogen at minus 196 degrees Celsius, to freeze targeted tissue. The goal is to achieve cellular destruction through rapid freezing followed by slow thawing. The target temperature for destroying benign cells is minus 20 degrees Celsius, while cancerous cells require minus 50 degrees Celsius due to their greater resistance to cell death. Melanocytes are particularly susceptible to cold injury and may die at temperatures below minus 5 degrees Celsius.

Understanding the concept of isotherms is critical in cryosurgery. Isotherms represent zones of spherical freezing where the temperature is constant at a given radius from the center of the cryogen application. For example, a minus 5 degree Celsius isotherm may extend 10 millimeters from the center at both depth and surface, while a minus 10 degree Celsius isotherm might be located 5 millimeters from the center. This predictable pattern allows surgeons to achieve the desired temperature at specific depths by monitoring the periphery of the freezing zone.

Intracanal Cryotherapy

In endodontic applications, intracanal cryotherapy involves irrigation of the root canal with cold saline following standard cleaning and shaping procedures. A 2025 systematic review and meta-analysis examined this technique for reducing post-endodontic pain, comparing its efficacy to that of steroids.

Hyperbaric Gaseous Cryotherapy

Developed in 1993, hyperbaric gaseous cryotherapy, also known as NeuroCryoStimulation, applies carbon dioxide at minus 78.3 degrees Celsius with a pressure of 5.0 megapascals and a frequency of 400 Hertz directly to the skin over painful areas. This technique is used by physicians and physiotherapists for its analgesic, vasomotor, anti-inflammatory, and muscle relaxant effects.

2. Mechanisms of Cellular Injury

Cryotherapy induces tissue damage through two primary mechanisms. The first mechanism is direct cellular injury from ice crystal formation. As tissue cools, ice crystals form between cells, creating an osmotic gradient that rapidly draws water out of the cells, leading to cellular dehydration and protein denaturation. With continued cooling, crystals form within the cells themselves, potentially causing rupture of cellular membranes and organelles. The thawing process contributes additional damage as crystals outside the cells melt, creating a reverse gradient that draws water rapidly back into cells, causing them to swell and burst. The ideal destructive cycle involves rapid freezing followed by slow thawing, and multiple freeze-thaw cycles increase the extent of tissue damage.

The second mechanism is vascular injury leading to ischemia. Cold damages blood vessels and capillaries in the target area, causing vasoconstriction and endothelial injury. As tissue rewarms, blood clots form within the damaged vessels, blocking blood flow and producing ischemic necrosis. This vascular effect means that even cells surviving the initial freeze may die later from lack of oxygen and nutrients.

3. Physiological Effects of Whole-Body Cryotherapy

The 2026 pilot study documented several significant physiological changes following 18 sessions of whole-body cryotherapy over nine weeks. Waist circumference decreased from an average of 83.8 centimeters at baseline to 80.2 centimeters post-intervention, representing a statistically significant reduction. Total body water, lean body mass, intracellular water, and extracellular water all showed significant time-dependent improvements.

Immune modulation was also observed. Lymphocytes increased from 25.6 percent to 29.3 percent of white blood cells, while granulocytes decreased from 63.5 percent to 58.7 percent. Anti-inflammatory interleukin-10 levels in virus-stimulated blood samples rose markedly from 33.5 to 63.5 picograms per milliliter. Interferon-gamma also increased over time. Soluble ACE2, a biomarker relevant to COVID-19 severity, decreased from 0.5 to 0.3 nanograms per milliliter at follow-up.

Perceived stress improved significantly across several domains of the Trier Inventory for Chronic Stress, including work overload and pressure to succeed.

4. Contraindications and Safety Considerations

A 2025 position paper from the Whole-Body Cryostimulation Working Group of the International Institute of Refrigeration established consensus contraindications based on a Delphi process involving 28 European experts. The panel identified both absolute and temporary contraindications for whole-body cryotherapy.

Absolute contraindications include pregnancy, severe hypertension with blood pressure exceeding 180 over 100, acute or recent myocardial infarction, unstable angina, arrhythmias, symptomatic cardiovascular disease, presence of a pacemaker, peripheral arterial occlusive disease, venous thrombosis, acute or recent cerebrovascular accident, uncontrolled seizures, Raynaud's syndrome, fever, active tumor disease, symptomatic lung diseases, blood clotting disorders, severe anemia, acute infections, cold allergies, cold agglutinin disease, acute kidney and urinary tract diseases, and increased intraocular pressure such as glaucoma.

Additional precautions include limiting caffeine consumption to no more than four cups per day and alcohol to no more than two drinks per day before treatment sessions. Substantial dietary changes, extreme sports participation, and other cold applications such as ice bathing should also be avoided during a course of treatment.

Safety incidents have occurred with cryotherapy equipment. In October 2015, a worker at a Nevada cryotherapy center died after entering a whole-body cryotherapy chamber alone and without supervision. The coroner determined that death occurred within minutes from suffocation due to nitrogen gas displacement of oxygen. This tragic event underscores the critical importance of proper supervision and safety protocols.

5. Time of Exposure and Frequency

For whole-body cryotherapy, sessions typically last two to four minutes. The 2026 research protocol administered 18 sessions over nine weeks, averaging two sessions per week. Each session lasted three to six minutes at minus 90 degrees Celsius.

For cryosurgery, treatment duration depends on the size and type of lesion. The freeze-thaw cycle is carefully monitored, and multiple cycles may be applied in a single session. The procedure is typically completed in minutes for skin lesions but may require longer for internal tumors guided by imaging.

For intracanal cryotherapy, the intervention consists of a single application of cold saline irrigation during the root canal procedure. The 2025 meta-analysis found this single application significantly reduced postoperative pain at 24 to 72 hours compared to controls.

6. Preconditioning Requirements

Before initiating whole-body cryotherapy, a thorough medical evaluation is essential to rule out contraindications. The 2026 study required preclinical medical diagnosis by the leading study physician to confirm eligibility. Participants were instructed to avoid substantial dietary changes, extreme sports, and other cold applications such as ice bathing before and during the treatment period.

For cryosurgery, hyperkeratotic lesions may require debulking before the procedure because keratin is a poor conductor of cold and can reduce treatment effectiveness.

7. Time of the Day

Research specifically examining optimal timing for cryotherapy is limited. In clinical practice, scheduling is typically determined by practical considerations rather than circadian factors. However, the 2026 whole-body cryotherapy study conducted measurements at consistent time points: at baseline directly before the first treatment, after nine weeks directly after the last treatment, and at a nine-week follow-up visit.

8. Dietary Considerations

The 2026 whole-body cryotherapy study excluded individuals consuming more than four cups of coffee per day or more than two alcoholic beverages per day. While not explicitly stated as dietary restrictions for all patients, these criteria suggest that excessive caffeine and alcohol consumption may interfere with treatment or increase risk.

9. Signs to Be Wary Of

Patients undergoing cryotherapy should be monitored for adverse reactions. For whole-body cryotherapy, signs requiring immediate attention include severe discomfort, chest pain, difficulty breathing, dizziness, or signs of cold injury such as frostbite. The protective equipment including gloves, headband, and mask must be worn properly to prevent cold-related injury to extremities and sensitive areas.

For cryosurgery, patients should be informed of expected post-treatment effects including redness, swelling, blistering, and possible scarring. Signs of infection such as increasing pain, pus, or fever require medical evaluation.

For all forms of cryotherapy, individuals with Raynaud's syndrome, cold allergies, or any of the contraindications listed above should not undergo treatment.

Mechanisms of Action: How Cryotherapy Works

Cryotherapy operates through several distinct but interrelated mechanisms depending on the intensity and duration of cold application.

At the cellular level, extreme cold destroys tissue through ice crystal formation and osmotic injury. During rapid freezing, ice crystals form within cells, mechanically disrupting membranes and organelles. During slower freezing, ice forms outside cells, drawing water out and creating toxic concentrations of electrolytes that denature proteins. The subsequent thawing process causes additional injury as water rushes back into dehydrated cells, causing them to swell and burst. Multiple freeze-thaw cycles maximize destruction.

At the vascular level, cold induces vasoconstriction and damages endothelial cells lining blood vessels. As tissue rewarms, platelet aggregation and microthrombus formation block blood flow, producing ischemic necrosis. This vascular effect ensures that cells at the periphery of the frozen zone, which may have survived the initial freeze, ultimately die from lack of oxygen and nutrients.

At the systemic level, whole-body cryotherapy modulates immune function and reduces inflammation. The 2026 study demonstrated increased anti-inflammatory interleukin-10, decreased granulocytes, and increased lymphocytes following repeated exposure. These changes suggest a shift toward improved immune regulation and reduced inflammatory tone.

Cryotherapy also preserves the extracellular matrix, the structural scaffold of tissues. Unlike heat-based treatments that denature collagen and other matrix proteins, cold maintains the tissue framework. This preservation allows for better healing, as new cells can repopulate the intact scaffold, and is particularly important in applications such as cryoneurolysis where nerve regrowth is desired.

In oncologic applications, cryotherapy may trigger an immune response against tumors. When cancer cells are destroyed by freezing, their antigens are released and presented to the immune system. This immunogenic cell death can stimulate a systemic response that targets cancer cells throughout the body, a phenomenon known as the abscopal effect.

Detailed Explanations of Cryotherapy's Impact

Physiological Impact

Whole-body cryotherapy produces measurable changes in body composition. The 2026 study documented significant reductions in waist circumference and increases in lean body mass and body water compartments over nine weeks of treatment. These changes suggest improved metabolic health and body composition, though the mechanisms require further investigation.

Cardiovascular responses to cold exposure include initial vasoconstriction followed by reflexive vasodilation. Heart rate may increase, and blood pressure shows characteristic changes. Research has demonstrated that whole-body cold stimulation improves cardiac autonomic control, with increased parasympathetic tone after exposure.

In athletic applications, cryotherapy reduces delayed onset muscle soreness after exercise. The cold reduces muscle metabolism, decreases microcirculation in the skin, lowers receptor sensitivity, and slows nerve conduction velocity. These effects combine to alleviate pain and promote recovery.

For musculoskeletal conditions, cryotherapy reduces inflammation and pain. A 2023 case report documented improved pain management and disease activity in active rheumatic polymyalgia following whole-body cryostimulation. Studies in elderly men have shown benefits for back pain therapy with frequent treatments.

Impact on Biomarkers

The 2026 whole-body cryotherapy study documented several significant biomarker changes.

Immune markers shifted toward improved regulation. Lymphocytes increased significantly from 25.6 percent to 29.3 percent of white blood cells. Granulocytes decreased from 63.5 percent to 58.7 percent. These changes indicate a favorable shift in immune cell distribution.

Cytokine responses showed enhanced anti-inflammatory capacity. Virus-stimulated interleukin-10, a potent anti-inflammatory cytokine, increased more than 80 percent from 33.5 to 63.5 picograms per milliliter. Interferon-gamma also increased significantly, suggesting enhanced immune readiness. These findings support the hypothesis that cryotherapy modulates immune function in ways that may improve resistance to infection and reduce inappropriate inflammation.

Soluble ACE2, a receptor for SARS-CoV-2 and a marker of COVID-19 severity, decreased from 0.5 to 0.3 nanograms per milliliter at follow-up. This reduction suggests potential relevance for post-COVID recovery and viral susceptibility.

Body composition biomarkers improved significantly. Waist circumference decreased from 83.8 to 80.2 centimeters. Total body water, lean body mass, and both intracellular and extracellular water compartments increased, indicating improved hydration status and muscle mass.

Perceived stress biomarkers from the Trier Inventory for Chronic Stress showed significant improvements in multiple domains including work overload and pressure to succeed, demonstrating psychological benefits alongside physiological changes.

Neurological Impact

Cryotherapy affects the nervous system through multiple pathways. Cold slows nerve conduction velocity, reducing pain signal transmission. This effect underlies the use of cryotherapy for acute pain relief and for chronic pain conditions such as fibromyalgia and neuralgias.

The autonomic nervous system responds to cold exposure with characteristic changes. Research has documented increased parasympathetic tone following whole-body cryotherapy, indicating improved autonomic balance and stress resilience. The 2026 study's finding of reduced perceived stress scores provides subjective confirmation of these physiological changes.

For neurological conditions such as multiple sclerosis, cryotherapy has been used clinically to reduce spasticity and improve function, though evidence quality varies.

Stress and Hormesis Impact

Cold exposure represents a form of hormesis, a beneficial stress response where low-dose challenges activate adaptive cellular pathways. The brief, controlled stress of extreme cold triggers the release of heat shock proteins, anti-inflammatory cytokines, and other protective molecules that enhance cellular resilience to future stressors.

The 2026 study documented this hormetic effect through increased anti-inflammatory interleukin-10 and improved stress perception scores. Participants reported less work overload and pressure to succeed after nine weeks of treatment, suggesting that regular cold exposure improved their capacity to handle daily stressors.

This hormetic adaptation may explain many of the reported benefits of cryotherapy, from improved immune function to better mood and cognitive performance.

Possible Conditioning Response and Steps to Optimize Healing

With regular cryotherapy sessions, the body develops a conditioning response characterized by more efficient thermoregulation, improved autonomic balance, and enhanced stress resilience. The 2026 study's nine-week protocol with 18 sessions provided sufficient exposure to induce these adaptive changes.

To optimize healing outcomes, several steps are recommended.

Ensure proper medical screening before initiating cryotherapy to rule out contraindications. The Delphi consensus contraindications provide a comprehensive framework for patient selection.

Maintain consistent treatment schedules. The 2026 protocol of two sessions per week for nine weeks produced significant benefits across multiple outcome measures.

Protect vulnerable areas during whole-body sessions. Proper use of gloves, headbands, masks, and dry footwear prevents cold injury.

Avoid combining cryotherapy with other intense cold exposures such as ice bathing during the treatment period.

For cryosurgery patients, follow post-procedure care instructions carefully, keeping the area clean and protected while healing occurs.

Address other health factors including nutrition, sleep, and stress management to maximize the benefits of cryotherapy as part of an integrated approach to wellness.

Conditions That Can Benefit from This Therapy

Based on clinical and scientific evidence, cryotherapy may benefit a wide range of conditions.

Dermatologic Conditions represent the most established application. Cryosurgery effectively treats warts, moles, skin tags, actinic keratoses, and certain skin cancers. The procedure is quick, cost-effective, and produces excellent cosmetic outcomes. A 2025 study in solid organ transplant recipients found that sequential treatment with cryotherapy followed by tirbanibulin ointment improved lesion clearance and prevented new actinic keratoses compared to cryotherapy alone.

Oncologic Applications include cryoablation of tumors in the prostate, kidney, liver, lung, and bone. The procedure can be performed percutaneously with imaging guidance, offering a minimally invasive option for patients who are not surgical candidates. The immunogenic cell death triggered by cryoablation may enhance systemic anti-tumor immunity.

Musculoskeletal Conditions benefiting from cryotherapy include rheumatoid arthritis, ankylosing spondylitis, osteoarthritis, fibromyalgia, and chronic back pain. A 2015 study documented benefits for back pain therapy in elderly men receiving frequent whole-body cryotherapy treatments.

Sports Medicine Applications include prevention and treatment of delayed onset muscle soreness, acceleration of post-exercise recovery, and management of acute injuries. Many elite athletes regularly use cryotherapy as part of their training and recovery protocols.

Neurological Conditions where cryotherapy may help include multiple sclerosis for spasticity management and various neuropathic pain syndromes. Cryoneurolysis, which freezes nerve fibers while preserving the surrounding nerve sheath, offers targeted pain relief with potential for nerve regeneration.

Rheumatologic Conditions including rheumatoid arthritis and polymyalgia rheumatica have shown positive responses to whole-body cryotherapy in case reports and small studies, with reduced pain and disease activity.

Mental Health and Stress applications are supported by the 2026 study's findings of reduced perceived stress scores. Improved mood and reduced depressive symptoms have also been reported.

Dental Applications include intracanal cryotherapy for post-endodontic pain reduction. The 2025 meta-analysis of 12 randomized controlled trials with 1,383 participants found that cryotherapy significantly reduced postoperative pain at 24 to 72 hours compared to steroids or control, with minimal side effects.

Metabolic Health improvements including reduced waist circumference and improved body composition were documented in the 2026 study, suggesting potential applications in obesity management.

Clinical and Scientific Evidence

The evidence base for cryotherapy has grown substantially in recent years, with high-quality studies across multiple applications.

The most recent and comprehensive whole-body cryotherapy study was published in January 2026 in the Journal of Clinical Medicine. This exploratory one-armed pilot study investigated 19 healthy adults with mean age 52.9 years who completed 18 whole-body cryotherapy sessions at minus 90 degrees Celsius over nine weeks, followed by a nine-week follow-up period. The study documented significant improvements in waist circumference, body composition, immune parameters including lymphocytes, granulocytes, anti-inflammatory interleukin-10, and soluble ACE2, as well as perceived stress scores. These findings provide effect-size estimates for future randomized controlled trials and support the feasibility and physiological relevance of whole-body cryotherapy.

A 2025 Delphi consensus study published in Frontiers in Rehabilitation Sciences established comprehensive contraindications for whole-body cryostimulation. A multidisciplinary panel of 28 European experts participated in a two-round Delphi survey, reaching consensus on absolute and temporary contraindications. This work provides a robust evidence framework to improve clinical practice and patient safety.

A 2025 systematic review and meta-analysis published in the Journal of Neonatal Surgery examined intracanal cryotherapy for post-endodontic pain. The analysis included 12 randomized controlled trials with 1,383 participants and found that cryotherapy significantly reduced postoperative pain at 24 to 72 hours compared to steroids or control, with a mean visual analog scale difference of minus 1.12. Minimal side effects were reported, supporting cryotherapy as a safe and effective alternative for pain management in endodontics.

A 2025 study published in the Journal of the American Academy of Dermatology examined sequential cryotherapy plus tirbanibulin for actinic keratosis in solid organ transplant recipients. At four months, the mean reduction in actinic keratoses was 81.6 percent in sequential treatment areas versus 53.4 percent with cryotherapy alone. Complete response rates were 51.4 percent with sequential therapy versus 10.8 percent with cryotherapy alone. Adverse effects were predominantly mild, demonstrating the value of combination approaches.

A 2024 systematic review, meta-analysis, and meta-regression published in the Journal of Thermal Biology examined the effects of cold exposure on cardiovascular and cardiac autonomic control responses in healthy individuals. The review provided evidence for the cardiovascular effects of cryotherapy and identified factors influencing individual responses.

A 2024 study in the Journal of Clinical Medicine demonstrated that whole-body cold stimulation improves cardiac autonomic control independently of the employed temperature, suggesting that the cold stimulus itself, rather than specific temperature parameters, drives beneficial autonomic adaptations.

A 2015 Cochrane systematic review examined whole-body cryotherapy for preventing and treating muscle soreness after exercise in adults. While calling for more research with active surveillance of adverse events, the review acknowledged the widespread use of cryotherapy in athletic settings and identified areas for future investigation.

The dermatologic cryosurgery literature is extensive, with the technique established as a standard of care for numerous skin conditions. The StatPearls chapter on cryotherapy in dermatology, updated in 2026, provides comprehensive coverage of indications, techniques, and outcomes.

Conclusion

Cryotherapy encompasses a diverse family of therapeutic cold applications, from precisely targeted destruction of skin lesions to systemic modulation of immune function through whole-body exposure. The evidence supporting these interventions has matured considerably, with recent high-quality studies documenting measurable changes in immune parameters, body composition, stress perception, and clinical outcomes across multiple conditions.

The 2026 whole-body cryotherapy study provides particularly valuable mechanistic data, demonstrating increased anti-inflammatory cytokines, improved lymphocyte profiles, reduced soluble ACE2, and decreased perceived stress following a nine-week protocol. These findings align with the clinical observations of reduced pain, improved recovery, and enhanced well-being reported by patients and athletes.

The 2025 Delphi consensus on contraindications represents an important step toward standardized safety protocols, helping clinicians identify patients who may benefit from cryotherapy while protecting those at risk of adverse events.

As with any therapeutic modality, proper patient selection, adherence to safety protocols, and realistic expectations are essential for optimal outcomes. The evidence suggests that when appropriately applied, cryotherapy offers a valuable tool for pain management, inflammation reduction, immune modulation, and tissue healing across a wide spectrum of medical conditions. Future research with larger randomized controlled trials will further refine protocols, identify optimal candidates, and expand the therapeutic applications of this versatile cold-based therapy.