Conditions A–Z
What the research says, condition by condition
452 studies on sauna, infrared and Waon therapy, and cold-water immersion, each checked against PubMed. We include the trials that found no benefit. A grade tells you how much weight the evidence can bear; it is not a verdict on whether any one patient should use it.
Therapy
Evidence grade
Showing 47 conditions (65 reviews)
A
Adhesive capsulitis of the shoulder
Joints & musculoskeletal
Allergic rhinitis
Respiratory
Ankylosing spondylitis / axial spondyloarthritis
Joints & musculoskeletal · reviewed for sauna and cold plunge
- SaunaIn a German randomized trial of 35 inpatients with ankylosing spondylitis, adding six sessions of water-filtered infrared-A whole-body hyperthermia (a clinic radiant-heat device) to physical therapy gave greater pain relief, less analgesic use and improvements in BASDAI and BASFI lasting up to 3-6 months, while HAQ did not change. In a small infrared-sauna pilot, pain and stiffness fell during sessions without increased disease activity. A randomized spa-exercise program that included sauna at one site improved a pooled symptom index at 4 weeks, but sauna's own contribution is unknown. Mechanistic studies report lower pro-inflammatory cytokines after whole-body hyperthermia and no cortisol or lymphocyte change after a single hot bath.Grade B7 studies
- Cold therapyMost cold-therapy studies in ankylosing spondylitis used whole-body cryotherapy (WBC), a 2-3 minute exposure to cold air at about -166 F in a chamber, which is a different method from a home cold plunge. A 2026 meta-analysis of 5 studies (310 patients) found WBC added to exercise improved disease activity (BASDAI, ASDAS), function and pain without a change in CRP, and a Russian randomized trial (n=82) found lower BASDAI and pain with WBC added to balneotherapy and exercise, with differences still present at 5-6 months. The only study including cold-water immersion, an 8-week program combining ice-water immersion and cold showers with breathing exercises and meditation (n=24), lowered ESR and ASDAS-CRP within the program group, but cold could not be isolated. Most trials were unblinded and short, and a 2026 reanalysis of one cohort found no effect on blood inflammatory indices.Grade C14 studies
Anxiety disorders
Mental health
Asthma
Respiratory · reviewed for sauna and cold plunge
- SaunaA German study of children with asthma monitored peak flow during Finnish dry sauna bathing and observed no complications except one asthma attack in a child using a cold shower afterwards, attributed to cold air. A Russian health-resort series of 107 patients with asthma or chronic bronchitis reported faster symptom regression and a bronchodilator effect when sauna was added to multimodal treatment, without a control group. Laboratory studies in asthmatic adults show that cooling the body with a cold shower and wind triggers bronchoconstriction, which is relevant to the cooling phase after a sauna.Grade C2 studies
- Cold therapyIn laboratory studies of asthmatic subjects, a 1-minute cold shower at 59 F followed by 1 minute of wind on the wet skin produced significant airway obstruction, while a warm shower or breathing the cold mist alone did not. Breathing warm humidified air during cooling substantially reduced the response, suggesting that body cooling leads to cooling of the airways. No trial has evaluated cold plunges, cold showers or whole-body cryotherapy as therapy in asthma.Caution2 studies
C
Cerebral palsy
Neurological
Cerebrovascular disease / history of ischemic stroke or TIA
Heart & circulation
Cholinergic urticaria
Skin
Chronic heart failure
Heart & circulation
Chronic kidney disease
Kidney
Chronic low back pain
Chronic pain · reviewed for sauna and cold plunge
- SaunaAn uncontrolled Korean study reported reduced pain and disability after ten 15-minute dry-sauna sessions in patients with low back pain. A randomized trial of mild whole-body hyperthermia added to inpatient multimodal therapy for chronic low back pain found a statistically significant but clinically non-relevant difference in disability. A Cochrane review found moderate evidence that heat wraps give small short-term relief in acute and subacute, not chronic, low back pain.Grade C4 studies
- Cold therapyCold-therapy studies in chronic low back pain have used whole-body cryotherapy (WBC), 2-3 minutes of cold air at about -202 to -256 F in a chamber, which is a different method from a home cold plunge. In a single-arm study of 41 patients, 20 WBC sessions over 5 weeks were followed by lower pain and disability scores. In older men, WBC before exercise improved lumbar mobility more than exercise alone, and daily sessions outperformed twice-weekly sessions. In 69 older women with lumbar spine arthritis, quality of life improved similarly with cryotherapy, cryotherapy plus exercise, and exercise alone, and the authors questioned the value of cryotherapy. Pain outcomes have not been tested against a no-WBC control in a randomized trial, and no cold-water immersion study was found.Grade C8 studies
Chronic obstructive pulmonary disease
Respiratory
Chronic pain syndrome
Chronic pain · reviewed for sauna and cold plunge
- SaunaIn a Japanese inpatient study of mixed chronic pain, adding daily far-infrared sauna (Waon-style) therapy to multidisciplinary treatment did not clearly improve pain scores beyond multidisciplinary treatment alone, since both groups improved. The sauna group had lower anger scores after treatment and a higher rate of return to work at 2 years. The study is small and the abstract does not report randomization.Grade C2 studies
- Cold therapyStudies of cold therapy in mixed chronic pain populations have used whole-body cryotherapy (WBC), a few minutes of cold air at about -157 F in a chamber, which is a different method from a home cold plunge. Uncontrolled series report pain relief lasting about 90 minutes after each session and improved mood and well-being after 10 sessions. In a controlled inpatient pilot, adding WBC to multimodal pain treatment did not produce more pain reduction than multimodal treatment alone. No cold-water immersion study in chronic pain was found.Grade C4 studies
Chronic tension-type headache
Chronic pain
Coronary artery disease (chronic ischemic heart disease)
Heart & circulation
D
Dyslipidemia / hypercholesterolemia
Metabolic
E
Essential (primary) hypertension
Heart & circulation · reviewed for sauna and cold plunge
- SaunaIn the Kuopio Ischaemic Heart Disease (KIHD) cohort, men who used a sauna 4-7 times per week had a lower risk of developing hypertension than men who used it once weekly; this is an association in initially normotensive men. Single sauna or hot-water immersion sessions acutely lower blood pressure in hypertensive patients (including central pressure after an ordinary home bath, without a difference in night-time pressure), but in a randomized crossover trial a single 185-194 F sauna session alone did not lower 24-hour ambulatory pressure; only exercise followed by sauna did. Older uncontrolled and non-randomized German studies reported lower resting pressure after months of regular sauna. Controlled evidence for a sustained effect is limited: an 8-week RCT found lower systolic pressure when sauna was added to exercise in adults with cardiovascular risk factors, while an 8-week sham-controlled RCT of home lower-leg hot-water immersion in hypertensive women found no change in ambulatory pressure. Meta-analyses of heat-therapy trials report modest systolic reductions (about 2-4 mmHg), but the most recent RCT-only meta-analysis found no significant overall effect on systolic or diastolic pressure.Grade B17 studies
- Cold therapyNo study has tested cold-water immersion or whole-body cryotherapy as a treatment for hypertension. Two small studies measured acute responses to whole-body cryotherapy chambers (-166 F to -193 F) in adults with hypertension: blood pressure rose after sessions, without a change in blood-pressure behavior over a 21-session course, and cardiovascular and autonomic responses differed between hypertensive and normotensive men. Sudden cold-water immersion triggers a cold shock response that includes a rise in blood pressure and heart rate.Caution2 studies
F
Fibromyalgia
Chronic pain · reviewed for sauna and cold plunge
- SaunaRandomized trials of mild water-filtered infrared whole-body hyperthermia, a clinic-delivered form of systemic heat, reduced fibromyalgia pain versus multimodal rehabilitation alone and versus sham hyperthermia; in the sham-controlled trial the difference was significant at weeks 4 and 30 but not at week 12, and responder rates did not differ. The only controlled sauna study is small and non-randomized: 12 mild sauna baths raised pressure pain thresholds by 22% versus 8% with exercise-pool sessions. Waon (140 F far-infrared sauna), sauna-plus-aquatic-exercise and hot-water immersion studies also report pain and FIQ improvements, but these were uncontrolled and small (8-44 patients). Sauna-specific randomized data are lacking.Grade A8 studies
- Cold therapyNo clinical trial of cold-water immersion, cold plunge or cold showers in fibromyalgia was found. Trials of whole-body cryotherapy (WBC), 1-3 minutes of cold air at about -89 to -202 F in a chamber, mostly report short-term improvements in pain, disease impact, sleep and quality of life, including a randomized trial in 43 patients with fibromyalgia and obesity in which WBC was added to rehabilitation. Results are not uniform: in a German comparison with peat baths and hot air (n=66), pain fell similarly in both groups and 53% stopped cryotherapy, including for panic symptoms, and an older 10-patient study found no significant pain advantage over controls. Benefits faded within about 3-4 months after a course ended, and WBC findings cannot be assumed to apply to water immersion.Grade C9 studies
Frailty in older adults
Other
G
Gout (acute gouty arthritis)
Joints & musculoskeletal
H
I
Insomnia
Neurological
L
M
Major depressive disorder
Mental health
Major depressive disorder and depressive symptoms
Mental health
Metabolic syndrome
Metabolic · reviewed for sauna and cold plunge
- SaunaOne uncontrolled Indian study gave 30 adults with diagnosed metabolic syndrome 10 sessions of dry-heat bathing (15 minutes at 140 F every third day for 30 days) and reported statistically significant pre-post changes in blood pressure, waist circumference, fasting glucose, HDL cholesterol and triglycerides, with no significant adverse changes in safety tests. The abstract does not report the size of the changes, and there was no control group. Related evidence on individual components is reviewed under hypertension, obesity, type 2 diabetes and dyslipidemia.Grade C1 study
- Cold therapyThree reports from one Polish research group studied 10-20 whole-body cryotherapy sessions (-184 to -202 F, 3 min) in postmenopausal women with metabolic syndrome, each compared with healthy women who received the same sessions. After 20 sessions, body mass, waist circumference and fat mass decreased in both groups, with additional reductions in trunk and android fat in the metabolic syndrome group. Fasting glucose and the glucose-regulating hormone asprosin decreased, mainly in women with hyperglycemia. No randomized or untreated control group, no long-term follow-up and no cold-water immersion study were found.Grade C3 studies
Mild cognitive impairment
Neurological · reviewed for sauna and cold plunge
- SaunaIn two Finnish population cohorts, people who used the sauna more often had a lower subsequent rate of diagnosed dementia, including Alzheimer's disease, after adjustment for cardiovascular and lifestyle factors. These are associations in people without cognitive impairment at baseline and may reflect residual confounding (healthier people may bathe more often). Interventional evidence is limited to a small feasibility study of hot-water immersion in cognitively healthy older adults at metabolic risk; a randomized trial is under way.Grade C3 studies
- Cold therapyWhole-body cryotherapy (brief exposure to extreme cold air in a chamber) has been studied in mild cognitive impairment by one Polish research group. In a double-blind, sham-controlled RCT of 62 adults with MCI, 10 sessions were followed by better immediate recall and orientation scores and improved mood compared with sham, but not on all measures and only over about 2 weeks. An uncontrolled pilot reported memory improvement, and adding WBC to computerized cognitive training reduced depressive symptoms without a clear added cognitive effect. No study has tested cold-water immersion in MCI or dementia.Grade C3 studies
Multiple sclerosis (heat sensitivity, Uhthoff phenomenon)
Neurological · reviewed for sauna and cold plunge
- SaunaHeat is a recognized trigger of temporary neurological worsening in multiple sclerosis (Uhthoff phenomenon), and the hot bath test was once used diagnostically because it provokes signs in a substantial share of patients. In heat-sensitive patients, a single moderate Finnish sauna session raised core temperature more than in healthy controls and acutely worsened walking, chair rise, functional reach and a processing-speed test, with recovery within an hour. Persistent deficits after a hot bath test and a fatal hyperthermia in a hot bath have been reported. Sauna is not a studied or supported treatment for MS; heat exposure is a caution or contraindication.Caution7 studies
- Cold therapyTwo different cold approaches have been studied in MS. Cooling for heat sensitivity: lowering body temperature can reduce heat-related conduction block, and a sham-controlled RCT and a meta-analysis support cooling garments, while water immersion has been tested only as 30 minutes of lower-body pre-cooling in 61-63 F water in 6 patients. Whole-body cryotherapy (WBC: 2-3 minutes in a cryogenic chamber at about -166 to -202 F) has been studied mainly by a few Polish groups: one randomized trial and several controlled or uncontrolled series report reductions in fatigue, EDSS or spasticity and improved hand grip, gait, mood, pain or sleep after 10-20 sessions, while most biochemical studies found no change. No serious adverse events were reported, and one study found no prothrombotic effect. Patient surveys also report that sharp cooling can worsen symptoms. A randomized pilot of a 12-week program combining cold exposure with breathing exercises and mindfulness reported better cognition, fatigue, anxiety and depression scores than no intervention, but did not isolate cold. This is not evidence for cold plunge at typical plunge temperatures, and cold is not a disease-modifying therapy.Grade C24 studies
Myalgic encephalomyelitis / chronic fatigue syndrome
Neurological · reviewed for sauna and cold plunge
- SaunaA Japanese group has reported reduced fatigue, improved mood and performance status after 4 weeks of daily far-infrared sauna (Waon) therapy in small uncontrolled series of inpatients with chronic fatigue syndrome, with no reported adverse effects. A related pilot reported symptom improvement alongside increased regional cerebral blood flow on SPECT. A 2025 German pilot in 9 patients described changes in blood-cell autophagy and mitochondrial markers after one session of medical whole-body hyperthermia but reported no clinical outcomes. There are no controlled trials.Grade C4 studies
- Cold therapyIn a Polish study, 32 patients with chronic fatigue syndrome completed 10 sessions of whole-body cryotherapy (brief extreme cold air in a chamber) combined with static stretching over 2 weeks. Fatigue decreased and some cognitive measures improved, and WBC was well tolerated; at 4 weeks the improvements were maintained in most of the 22 patients reassessed. There was no untreated or sham control, stretching was given to all, and cold-water immersion has not been studied in ME/CFS.Grade C2 studies
O
Osteoarthritis
Joints & musculoskeletal · reviewed for sauna and cold plunge
- SaunaNo published trial has tested sauna in osteoarthritis. In a randomized trial of 93 patients with severe hip or knee OA awaiting joint replacement, 12 weeks of hot-water immersion at 104 F improved aerobic threshold and lowered resting blood pressure but did not change subjective OA severity. Uncontrolled studies of daily whole-body mud baths at 104-108 F (36 older adults with knee OA) and a 10-day course of traditional fermenting-hay baths (27 patients with OA) reported improvements in pain, stiffness and function. Systematic reviews of local heat show short-term pain relief in hand OA but no clear benefit in knee OA.Grade C6 studies
- Cold therapyCold-therapy studies in osteoarthritis have used whole-body cryotherapy (WBC), a few minutes of cold air at about -166 F in a chamber, which is a different method from a home cold plunge. Uncontrolled and non-randomized studies, mostly in spinal osteoarthritis and combined with exercise, report reductions in pain and analgesic use. One randomized study in older women with lumbar spondyloarthrosis found reduced red-cell elasticity after WBC with exercise, which its authors considered a possible perfusion concern. No randomized trial with clinical outcomes and no cold-water immersion study was found.Grade C6 studies
Overweight and obesity
Metabolic · reviewed for sauna and cold plunge
- SaunaPassive heat alone has not produced weight loss in people with overweight or obesity. In a randomized trial of 66 overweight Japanese adults, hot bathing alone produced no significant improvements, while a program combining hot bathing with exercise and diet reduced weight and waist circumference more than the other arms. Small studies report lower fasting glucose and insulin after 10 hot-water immersions, better lipids and vascular compliance (but not fitness) after 12 weeks of half-body bathing compared with no treatment in obese men, improved quality-of-life scores after 8 dry-sauna sessions without change in body composition, and acute reductions in blood pressure and increases in limb and skin blood flow after one hot-water immersion. Weight lost during a sauna session is mainly fluid.Grade C11 studies
- Cold therapyAlmost all patient studies in obesity used whole-body or partial-body cryotherapy chambers (about -166 to -202 F for 2-3 minutes), not cold-water immersion; one laboratory crossover used a water-perfused cooling suit. In a 12-month lifestyle obesity program, adding 28 cryotherapy sessions did not increase weight loss (11.9% vs 11.5% at 5 months), although fasting glucose and LDL cholesterol fell more. In a randomized study of 65 overweight to obese adults, adding 10 sessions to interval training improved blood glucose but blunted some training-related changes. Small uncontrolled studies from a few research groups report reductions in inflammatory markers, leptin and body fat, increased resting energy expenditure, and better spinal and shoulder range of motion during rehabilitation; a 2022 scoping review judged the evidence insufficient for definitive conclusions. In a randomized crossover of 14 young men with obesity, 5 hours in a 60.8 F water-perfused suit lowered fasting glucose and improved glucose tolerance compared with a thermoneutral suit, an acute laboratory effect.Grade C13 studies
P
Parkinson disease
Neurological · reviewed for sauna and cold plunge
- SaunaIn a Chinese study, many patients with Parkinson disease reported that motor symptoms are worse in winter and temporarily better after hot baths. In 9 temperature-sensitive patients, motor examination scores (bradykinesia, rigidity, posture and rest tremor) were better after a hyperthermic bath than on a day without one. The effect was acute and temporary, the sample was small and selected, and sauna itself has not been studied in Parkinson disease.Grade C1 study
- Cold therapyWhole-body cryotherapy (2 minutes of extreme cold air in a chamber) has been tested in two small uncontrolled Italian pilot studies of people with Parkinson disease. After 10 sessions, one study reported lower cortisol and improved anxiety, depression, fatigue and sleepiness scores; the other reported increased heart rate variability with stable blood pressure. There are no controlled trials, motor symptoms were not the primary outcome, and cold-water immersion has not been studied.Grade C2 studies
Peripheral arterial disease of the lower extremities
Heart & circulation
Polycystic ovary syndrome
Metabolic
Post-COVID-19 condition (long COVID)
Other
Post-exercise muscle soreness
Other
Primary open-angle glaucoma
Other
Psoriasis
Skin
Psoriatic arthritis
Joints & musculoskeletal · reviewed for sauna and cold plunge
- SaunaIn a German randomized trial of 35 inpatients with psoriatic arthritis, adding six sessions of water-filtered infrared-A whole-body hyperthermia (a clinic radiant-heat device) to standardized physical therapy gave greater pain relief and less analgesic use than physical therapy alone, and DAS28 fell only in the hyperthermia group, with effects reported up to 6 months. Skin involvement (PASI) and ESR/CRP did not change in either group. The trial was small and unblinded, and no study has tested a conventional or infrared sauna in psoriatic arthritis.Grade B1 study
- Cold therapyNo study of cold-water immersion in psoriatic arthritis was found. In a German randomized trial reported as a congress abstract, 36 inpatients received multimodal rheumatology therapy with or without six sessions of whole-body cryotherapy (WBC, cold air at -166 to -274 F for 1.5-3 minutes); pain fell more with WBC and stayed lower for up to 3 months, and DAS28, HAQ and skin scores improved after treatment. WBC is a different method from a home cold plunge, and these findings cannot be assumed to apply to water immersion.Grade C1 study
Psychotic disorders (schizophrenia spectrum)
Mental health
R
Recurrent respiratory infections
Respiratory · reviewed for sauna and cold plunge
- SaunaA 1990 controlled trial reported about half as many common colds in the later months among volunteers taking regular saunas, with no difference in cold duration or severity, and a 1992 German study of 20 nursery-school children reported fewer respiratory infections and illness days over one year in those taking regular saunas. In the Finnish KIHD cohort, men who used the sauna 2 or more times per week had a lower rate of hospital-diagnosed pneumonia over about 25 years; in a later analysis the lowest risk was seen in men with both high fitness and frequent sauna use. Inhaling hot sauna air during an established cold did not reduce overall symptom severity in a randomized trial of 157 patients. The evidence concerns prevention in healthy adults and children rather than treatment in people with documented recurrent infections.Grade C6 studies
- Cold therapyA pragmatic Dutch RCT randomized 3018 adults without severe comorbidity to end their daily shower with 30, 60 or 90 seconds of cold water (about 50-54 F) for 30 days or to control; self-reported sickness absence from work was 29% lower, but the primary outcome of illness days did not differ. In preschool children with frequent colds, 12 months of daily warm-and-cold hydrotherapy did not reduce cold incidence or duration in a randomized trial. Small uncontrolled studies of cold affusions in COPD and children reported fewer infections, and in a survey of 2343 adults, physically active cold-water swimmers less often reported frequent respiratory infections but did not have lower COVID-19 incidence. A 2025 healthy-adult meta-analysis summarized immune effects as non-significant short term.Grade C6 studies
Restless legs syndrome
Neurological
Rheumatoid arthritis
Joints & musculoskeletal · reviewed for sauna and cold plunge
- SaunaSauna use in rheumatoid arthritis has been studied only in small uncontrolled series. An infrared-sauna pilot reported statistically significant short-term reductions in pain and stiffness during sessions, with no rise in disease activity, but changes across a 4-week course did not reach significance. No randomized trial of whole-body sauna exists in RA, and a randomized trial of local dry heat (fluidotherapy) to the hands showed no benefit.Grade C4 studies
- Cold therapyMost controlled cold-therapy evidence in rheumatoid arthritis comes from whole-body cryotherapy (WBC), a 2-3 minute cold-air chamber exposure at -166 to -202 F, which is a different method from a home cold plunge. A single-blinded RCT in 56 patients with active RA found WBC added to inpatient treatment reduced pain by 1.31 points on a 0-10 scale, and uncontrolled series report lower DAS28 and pain. When WBC was compared with local cold or conventional physical therapy, however, pain and disease activity improved similarly in all groups. Water-based data are limited to a cold mist shower crossover trial (modestly lower weekly pain) and a feasibility study of exercise with cold-water immersion that reported no flares.Grade C13 studies
S
Spinal cord injury (tetraplegia and paraplegia)
Neurological · reviewed for sauna and cold plunge
- SaunaSmall laboratory studies show that people with tetraplegia or paraplegia can complete a supervised sauna session or hot-water immersion without syncope, with rises in heart rate, core temperature and interleukin-6 similar to those after exercise. People with cervical injury had blunted sympathetic responses (no catecholamine rise) and a fall in diastolic pressure after sauna. Cerebrovascular function was unchanged by mild heating. In a German study of a single 185 F sauna, skin temperature rose more in people with spinal cord injury than in controls, and low paraplegia was followed by hemoconcentration and higher blood viscosity. No study has tested regular sauna or heat therapy for cardiovascular, functional or symptom outcomes in spinal cord injury.Grade D6 studies
- Cold therapyOne randomized trial has tested cold exposure in people with chronic spinal cord injury: 62 adults (37% tetraplegia) were assigned to a 7-week Wim Hof Method program with cold showers, the same program of breathing and mindset training without cold, or usual care. Mental health, the primary outcome, did not differ between groups. Compared with usual care, the cold-exposure group reported less pain interference and improved inspiratory flow and fasting glucose, but the two program groups did not differ from each other. Cold showers at home averaged 58 F (14.6 C) and were tolerated without serious adverse events or autonomic dysreflexia.Grade C1 study
T
Tinnitus
Other
Type 1 diabetes mellitus
Metabolic
Type 2 diabetes mellitus
Metabolic · reviewed for sauna and cold plunge
- SaunaHeat therapy has been proposed to improve insulin sensitivity, but trials in type 2 diabetes have not shown glycemic benefit. Single sessions of infrared sauna or hot-water immersion did not improve glucose tolerance or insulin sensitivity in four small crossover trials, and heating close to a glucose load transiently raised glucose. Two uncontrolled studies of 8-10 hot-water immersions over 2 weeks reported improved fasting insulin sensitivity and lower systolic blood pressure without changes in glucose or endothelial function, and meta-analyses found no significant effect on HbA1c or fasting glucose. In a cross-sectional study of 1,297 patients, frequent hot-tub bathing was associated with slightly lower HbA1c.Grade C13 studies
- Cold therapyInterest in cold for type 2 diabetes stems mainly from small Dutch studies of mild cold acclimation in cold rooms (ambient air at 57-63 F for several hours a day), not from cold-water immersion. A 10-day study in 8 patients reported an approximately 43% increase in peripheral insulin sensitivity, but a follow-up in 9 patients without shivering found no improvement, and a 2026 randomized crossover study using a water-perfused suit found that one mild-cold session with shivering lowered 24-hour glucose in type 2 diabetes but not prediabetes. A non-randomized study of 30 whole-body cryotherapy sessions (-184 F, 3 min) in postmenopausal women with type 2 diabetes reported lower fasting glucose and HbA1c, without effect sizes in the abstract. In healthy adults, 16 daily 10-minute immersions at 57 F temporarily reduced insulin sensitivity and glucose tolerance, and foot contrast baths did not increase skin blood flow in patients with type 2 diabetes.Grade C10 studies
How we grade
Grades describe the evidence in patients who have the condition. Studies in healthy volunteers, or of a different heat or cold method, are labeled and count for less.
- Grade A· Strong
- Two or more randomized trials in patients show benefit with no larger trial disagreeing, or a meta-analysis of controlled trials in patients shows benefit.
- Grade B· Moderate
- At least one randomized trial in patients shows benefit, or several controlled trials agree, or a large cohort shows a dose-response plus a supportive study in patients.
- Grade C· Emerging
- Early studies in patients point to benefit, or cohort associations, or mixed results. More trials are needed.
- Grade D· Insufficient
- Not yet studied in patients with this condition and no cohort data, or the studies found no benefit or found harm.
A grade measures the research, not the therapy.
Most conditions on this list have never had a large trial: heat and cold therapies are rarely studied at the scale of a new drug. A C or D grade means the evidence is still emerging or has not been gathered, not that the therapy has been shown not to work. Where trials did find no benefit, we show them. Whether the evidence is enough for a given patient is a clinical judgment, which is why the decision belongs to the treating clinician.