The Perils of the Plunge: An Evidence-Based Examination of Cold Water Immersion Dangers in Sweden

I. Executive Summary

Cold Water Immersion (CWI), including traditional Swedish "kallbad," is experiencing a surge in popularity, often promoted as a panacea for various health and wellness concerns. This report provides a comprehensive analysis of the significant physiological dangers associated with CWI, critically evaluates the scientific evidence underpinning its purported benefits, and examines the specific context of CWI practices in Sweden, with a focus on emerging communities in Umeå.

The primary dangers of CWI are acute and potentially life-threatening. The Cold Shock Response (CSR), an involuntary gasp and hyperventilation upon sudden cold exposure, poses an immediate drowning risk. Simultaneously, "autonomic conflict" – the clashing signals from the sympathetic and parasympathetic nervous systems – can trigger severe cardiac arrhythmias, potentially leading to sudden death, which may be misattributed to drowning. CWI significantly increases cardiovascular strain, elevating heart rate and blood pressure, posing substantial risks to individuals with known or undiagnosed heart conditions. Hypothermia remains a critical danger, accelerated by water's thermal conductivity, impairing cognitive and physical function. Furthermore, Non-Freezing Cold Injuries (NFCIs) can cause permanent nerve damage and chronic pain, even from short immersions.

A critical review of scientific literature reveals that while some studies suggest benefits for mood or stress reduction, the evidence base for many widespread claims regarding immunity, inflammation, and metabolic health is constrained by methodological limitations, including few high-quality randomized controlled trials, small sample sizes, and a lack of standardized protocols. In some instances, such as post-exercise recovery, CWI may even blunt desired physiological adaptations like muscle growth.

In Sweden, while general statistics on drowning and cold-related injuries exist, there is a significant data gap concerning incidents directly attributable to recreational CWI practices. This makes it challenging to quantify the precise risk level of this cultural trend from epidemiological data alone. Vulnerable populations, including individuals with cardiovascular diseases, respiratory conditions, diabetes, the elderly, children, and those on certain medications or under the influence of alcohol, face markedly increased risks.

The emergence of CWI communities in Umeå, such as Umeå Kallbad, reflects growing local interest. While these groups may promote community and connection with nature, and often mention safety, the specifics of their medical pre-screening protocols for all participants and the detailed content of their safety guidelines were not fully evident from the available information. The proliferation of a "CWI therapy belief system," which often overstates benefits while understating scientifically validated risks, is a significant concern. This belief system can encourage unprepared or unsuitable individuals to engage in a hazardous activity without full awareness of the potential consequences.

Key recommendations include:

For Individuals: Mandatory medical pre-screening before starting CWI, gradual acclimatization, never immersing alone, understanding personal limits and risks, controlled entry and breathing, limited exposure times, and proper rewarming.

For Organizers (e.g., in Umeå): Implementing robust safety briefings, medical screening procedures, ensuring trained supervision, having comprehensive emergency plans and equipment, and promoting realistic expectations by clearly communicating both potential benefits and documented risks.

For Public Health Authorities: Developing and disseminating official, evidence-based guidelines on recreational CWI; improving data collection on CWI-related incidents; funding high-quality research; and educating healthcare professionals about CWI-specific risks.

This report underscores the necessity for a cautious, evidence-based approach to CWI, prioritizing safety and informed consent over unsubstantiated therapeutic claims.

II. Introduction: The Growing Trend of Cold Water Immersion in Sweden and Umeå

Cold Water Immersion (CWI), the practice of submerging the body in cold water, typically between 10-15°C or lower, has garnered significant global attention and participation in recent years.1 This trend is particularly resonant in Nordic countries like Sweden, where traditions such as "kallbad" (cold bath) or "vinterbad" (winter bathing), often combined with sauna use, have historical roots.3 Proponents frequently tout CWI as a powerful tool for enhancing physical health, mental wellbeing, reducing inflammation, boosting immunity, and even improving metabolic function.1

The allure of CWI has led to the formation of dedicated communities and an increase in organized CWI activities. As highlighted in the user's query, the city of Umeå in northern Sweden is witnessing such a development, with local groups like "Umeå Kallbad" actively promoting communal cold bathing experiences and aspiring to establish dedicated facilities.4 This growth reflects a broader societal embrace of CWI, often framed within a "therapy belief system" that emphasizes its perceived restorative and performance-enhancing qualities.

However, the rapid popularization of CWI, often fueled by anecdotal accounts and media portrayals 1, may be occurring without a commensurate public understanding of the inherent physiological risks. This report aims to conduct a deep research analysis of the dangers associated with CWI, with a particular focus on cold bath immersions in the Swedish context. It will critically evaluate the scientific underpinnings of the "cold water immersion therapy belief system," investigate available data on cold-related fatalities and incidents in Sweden, and examine safety practices related to CWI, specifically considering the emerging communities in Umeå. The objective is to provide an evidence-based perspective on the potential hazards of this increasingly widespread practice.

III. The Science of Cold: Physiological Dangers of Cold Water Immersion

Immersion in cold water elicits a cascade of powerful physiological responses, many of which can pose significant and immediate threats to health and survival. Understanding these responses is crucial for appreciating the inherent dangers of CWI, regardless of its purported benefits.

A. The Initial Shock: Cold Shock Response (CSR), Autonomic Conflict, and Drowning Risk

The body's initial reaction to sudden cold water immersion is swift and can be overwhelming. This "Cold Shock Response" (CSR) is a life-threatening reflex evoked even in water temperatures considered moderate by some CWI enthusiasts (e.g., 10-15°C), and the gasp reflex can be triggered by water as warm as 25°C.8 The CSR is characterized by an involuntary gasp for air, followed by uncontrollable hyperventilation (rapid, deep breathing).8 This dramatically increases the risk of inhaling water and subsequent drowning, even for competent swimmers and in calm waters.8 The first few minutes of immersion are particularly perilous due to these uncontrolled respiratory reflexes.9 It is noteworthy that the severity of the CSR is not always directly proportional to how cold the water is below a certain threshold; water at 10-15°C can elicit a cold shock response as dangerous as water near freezing.9 This reality means that participants might dangerously underestimate the risks in water that is not perceived as "ice-cold," focusing on the temperature rather than the body's profound physiological reaction to sudden cooling.

Compounding the respiratory dangers is the phenomenon of "autonomic conflict".11 When an individual is submerged in cold water, especially if the face is immersed and breath is held (as is common in the diving response), two powerful and antagonistic parts of the autonomic nervous system are simultaneously activated. The CSR triggers a sympathetically driven tachycardia (increased heart rate), while the diving response promotes a parasympathetically mediated bradycardia (decreased heart rate).11 This strong, simultaneous co-activation of opposing drives to the heart can lead to a high incidence of cardiac arrhythmias, including potentially fatal ones.11 Crucially, such electrical disturbances of the heart are typically undetectable post-mortem.11 Consequently, deaths that occur rapidly in cold water, which might have been due to these arrhythmias, are often misattributed to drowning (if water is aspirated during agonal gasps) or, less commonly, to hypothermia, especially if the immersion period is too short for severe hypothermia to develop.11 This potential for misattribution means that the true incidence of CWI-related cardiac fatalities may be underestimated in official statistics.

B. Cardiovascular Under Stress: Arrhythmias, Blood Pressure, and Cardiac Workload

Beyond the initial autonomic clash, CWI imposes significant stress on the cardiovascular system. The cold shock triggers a sudden and marked increase in heart rate and blood pressure.9 This surge elevates cardiac workload and myocardial oxygen demand, as the heart must work harder to pump blood against constricted peripheral blood vessels.12

For individuals with pre-existing cardiovascular diseases (CVD), whether diagnosed or undiagnosed, these responses can be particularly dangerous and are often aggravated.12 In those with hypertension, the cold-induced pressor response can be exaggerated.12 For individuals with coronary artery disease (CAD), cold exposure can reduce myocardial oxygen supply due to impaired vasodilation or even constriction of diseased coronary arteries, potentially leading to myocardial ischemia (insufficient blood flow to the heart muscle), angina (chest pain), and an increased risk of acute cardiac events.12 Patients with heart failure have limited physiological reserve to cope with the increased cardiac afterload imposed by cold-induced vasoconstriction.12 The promotion of CWI for "cardiovascular health" 10 can therefore be dangerously misleading for these individuals, as the practice can directly trigger the very events it is anecdotally claimed to prevent.

Furthermore, some research has indicated higher levels of troponin, a protein marker of heart muscle damage, in individuals who participate in winter swims.10 While these findings often relate to prolonged immersion, they raise concerns about the potential for repeated, even shorter, CWI sessions as part of a "therapy" regimen to induce subclinical myocardial damage over time, the long-term consequences of which remain largely unknown. Additionally, common medications for heart conditions, such as beta-blockers, which lower blood pressure and heart rate, can impair the body's ability to adapt to the sudden temperature drop, potentially making the cold shock response more hazardous.10 Dr. Jorge Plutzky, director of preventive cardiology at Brigham and Women's Hospital in Boston, has explicitly cautioned against CWI for anyone with a cardiac history.10

C. The Creeping Chill: Hypothermia and Its Complications

If exposure to cold water continues beyond the initial shock phase, hypothermia—a dangerous drop in core body temperature to below 35°C (95°F)—becomes an escalating threat.9 Water conducts heat away from the body approximately 25 times faster than air of the same temperature, meaning body heat is lost much more rapidly during immersion.10

Hypothermia progressively impairs both cognitive and physical functions.9 Thinking becomes clouded, decision-making falters, and muscular coordination deteriorates, significantly increasing the risk of drowning as individuals lose the ability to take self-rescue measures or even stay afloat.9 A report from the Swedish National Board of Health and Welfare (Socialstyrelsen) on hypothermia details various stages, noting that at severe levels (core temperature below 28°C), the body's thermoregulatory mechanisms essentially cease to function.14 The report also suggests that some elderly individuals found deceased outdoors, with death attributed to cardiovascular causes, might have actually succumbed to unrecognized hypothermia.14 The cognitive impairment associated with hypothermia is particularly insidious, as it can prevent individuals from recognizing their deteriorating condition or taking appropriate action, creating a perilous feedback loop where confusion leads to further inaction and worsening hypothermia.

The risk of hypothermia does not end upon exiting the water; "afterdrop," a continued cooling of the core body temperature, can occur. Therefore, proper and gradual rewarming procedures are essential immediately after CWI.10 The intense focus on the purported "rush" or "euphoric" feelings associated with CWI 7 might lead participants, especially novices or those in group settings, to ignore or misinterpret early warning signs of hypothermia, such as persistent shivering or mild confusion, in a desire to endure the cold or conform to group expectations.

D. Beyond the Core: Non-Freezing Cold Injuries (NFCI) and Other Physical Effects

Beyond the immediate life-threatening risks of drowning and cardiac events, and the systemic threat of hypothermia, CWI carries the risk of localized tissue damage. Non-Freezing Cold Injuries (NFCIs) are a significant and often underappreciated danger.7 Unlike frostbite, which typically requires sub-zero temperatures, NFCIs can occur from sustained exposure to cold, wet conditions at temperatures above freezing—conditions commonly encountered in CWI.7 These injuries, which can arise even after relatively short immersions, involve damage to peripheral nerves and blood vessels, potentially leading to chronic pain, persistent numbness, and permanent hypersensitivity to cold in the affected extremities.7 The long-term debilitating effects of NFCIs represent a serious chronic health risk that may not be immediately apparent to CWI participants.

Furthermore, cold water can rapidly induce physical incapacitation. Within seconds to minutes of immersion, there can be a significant loss of muscular control and strength in the arms, legs, hands, and feet as blood flow is shunted away from the extremities to protect the body's core.9 This neuromuscular impairment makes swimming or any self-rescue attempt extremely difficult, if not impossible, without the aid of a personal flotation device or immediate external assistance.9 This rapid onset of physical helplessness underscores that CWI is not merely a test of mental fortitude but involves profound physiological changes that can quickly render an individual vulnerable, irrespective of their initial swimming ability or fitness level.

IV. Continuous Immersion: Evaluating Long-Term Health Claims and Risks

The increasing popularity of CWI is largely driven by claims of its long-term benefits for physical and mental health. However, a critical examination of the scientific literature reveals a complex picture, with many purported advantages lacking robust evidentiary support, and some potential for adverse long-term consequences, particularly with frequent or continuous immersion.

A. A Critical Look at Purported Benefits (Mental Health, Immunity, Inflammation)

Mental Health: Many proponents of CWI report improvements in mood, stress reduction, and enhanced mental clarity.2 Some studies, often relying on self-reported questionnaires, have indicated decreases in negative emotions like tension and depression, and increases in vigor and self-esteem following CWI.2 There is some biochemical basis for these claims, with evidence suggesting that CWI can transiently increase plasma concentrations of endorphins, dopamine, and serotonin—neurotransmitters associated with pleasure, motivation, and mood regulation.2 Furthermore, adaptation to repeated cold exposure may lead to decreased baseline cortisol levels, a key stress hormone.2 However, the longevity of these neurochemical changes and their downstream biological effects on complex conditions like clinical anxiety or depression are unclear.7 As biologist François Haman notes, a temporary increase in these chemical messengers does not necessarily equate to a cure for underlying mental health issues.7 Moreover, it is challenging to disentangle the specific effects of cold from the psychological benefits derived from the social interactions, sense of accomplishment, or connection with nature often associated with group CWI practices.7

Immunity and Inflammation: Claims that CWI boosts the immune system and reduces inflammation are widespread.1 However, the scientific evidence is nuanced and, in some aspects, contradictory. A systematic review and meta-analysis found significant increases in inflammatory markers (indicating an acute inflammatory response) immediately and one hour after CWI.1 While this acute response could theoretically lead to adaptive anti-inflammatory effects in the longer term (a concept known as hormesis), the immediate effect is pro-inflammatory. The same review noted that while narrative synthesis suggested longer-term benefits such as a 29% reduction in sickness absence among participants who combined cold showers with regular exercise, the meta-analysis did not find significant effects on immune function markers immediately or one hour post-CWI.1 The notion that CWI is universally "anti-inflammatory" is an oversimplification; the acute pro-inflammatory response is a physiological reality that may not be beneficial for all individuals or if CWI is practiced too frequently, potentially leading to repeated inflammatory spikes.

Metabolism and Other Claims: CWI is also often purported to increase metabolic rate, aid in fat loss (particularly through the activation of "brown fat"), and even enhance focus and cognition.1 While cold exposure can indeed stimulate brown adipose tissue (BAT) activity and increase energy expenditure 15, the magnitude and sustainability of these effects for significant weight loss or metabolic improvement in the general population engaging in typical CWI practices remain subjects of ongoing research, with current evidence often described as weak or preliminary.1

A crucial overarching observation is that the evidence supporting many of these benefits is heavily reliant on subjective self-reports, observational studies, or short-term experiments with small sample sizes, rather than on rigorous, double-blind, randomized controlled trials (RCTs)—the gold standard for establishing medical efficacy.1 This makes it difficult to definitively establish causality and to rule out the influence of placebo effects, expectation bias, or other confounding variables.

B. The Limitations and Gaps in Current Scientific Evidence

The scientific investigation into CWI is hampered by several significant limitations. Systematic reviews consistently point out that the current evidence base is constrained by a scarcity of high-quality RCTs, small participant numbers in existing studies, and a lack of diversity in study populations (often focusing on young, healthy athletes).1

A major challenge is the lack of standardization in CWI protocols across studies.7 Variations in water temperature, duration of immersion, frequency of exposure, and the specific population studied make it exceedingly difficult to compare results, draw firm conclusions, or provide evidence-based recommendations on "optimal" CWI practices. This absence of standardized protocols means that even if a particular study demonstrates a benefit (or harm) under specific conditions, it is uncertain whether these findings apply to the diverse ways individuals practice CWI recreationally. This "wild west" scenario, where individuals may adopt extreme or frequent immersion routines based on anecdotal advice, inherently increases the risk profile.

Consequently, there is a clear need for more methodologically sound research, particularly high-quality RCTs, to thoroughly examine the long-term effects of various CWI regimens on diverse health outcomes and to identify safe and effective protocols, if any exist.1 In this current evidence vacuum, anecdotal evidence and personal testimonials often gain undue prominence 7, allowing the "therapy belief system" surrounding CWI to flourish with strong claims that are not always supported by robust scientific backing. This environment can make it challenging for individuals to make truly informed decisions about engaging in the practice.

C. Potential Adverse Long-Term Consequences

While much of the focus is on acute dangers, repeated or continuous CWI may also carry risks of adverse long-term health consequences. For athletes, a population that frequently uses CWI for post-exercise recovery, there is a growing body of evidence suggesting that regular CWI after training sessions can actually blunt desirable long-term adaptations, such as increases in muscle size (hypertrophy) and the development of muscular power and strength.1 This finding directly contradicts one of the primary purported benefits of CWI in athletic contexts, highlighting a potential disconnect where subjectively "feeling recovered" does not equate to positive physiological adaptation for performance enhancement.

As previously mentioned, the observation of increased troponin levels after some winter swimming activities raises concerns about potential cumulative heart muscle damage with prolonged or frequent exposure.10 Similarly, NFCIs can result in permanent cold sensitivity and chronic pain, significantly impacting quality of life.7

Furthermore, CWI acutely triggers significant physiological stress responses, including increases in heart rate, blood pressure, respiration rate, oxygen uptake, and the secretion of stress hormones like cortisol and norepinephrine.1 While acute, controlled stressors can sometimes lead to beneficial adaptations (hormesis), the long-term implications of repeatedly inducing these profound physiological changes remain largely unclear.1 Chronic or excessive exposure to such stressors without adequate recovery or in susceptible individuals could potentially lead to maladaptation and pathology. The "therapy" framing of CWI might inadvertently encourage individuals to pursue excessive exposure frequencies or durations in the belief that "more is better," without a clear understanding of these potential long-term trade-offs.

V. Identifying Vulnerability: Who is Most at Risk?

While CWI can pose risks to any individual, certain populations are significantly more vulnerable to its adverse effects due to pre-existing medical conditions, age, medications, or other factors. Recognizing these vulnerabilities is paramount for preventing harm.

A. Pre-existing Medical Conditions (Cardiovascular, Respiratory, etc.)

Individuals with cardiovascular conditions are at markedly increased risk during CWI. This includes those with:

Hypertension (High Blood Pressure): The cold-induced spike in blood pressure can be exaggerated, placing further strain on the cardiovascular system.12

Coronary Artery Disease (CAD): Reduced myocardial oxygen supply due to vasoconstriction can precipitate angina or myocardial infarction.12

Heart Failure (HF): The failing heart has diminished capacity to cope with the increased afterload and cardiac workload imposed by cold.12

Arrhythmias: A history of cardiac arrhythmias makes individuals more susceptible to the arrhythmogenic effects of autonomic conflict during CWI.11 Indeed, medical professionals strongly caution against CWI for anyone with a known cardiac history.10 A critical concern is that a substantial portion of the adult population may have undiagnosed cardiovascular conditions, such as asymptomatic hypertension or early-stage CAD. These individuals are unknowingly at high risk if they engage in CWI without prior, thorough medical assessment that specifically considers the stresses of cold immersion.

While less extensively detailed in the provided materials than cardiovascular risks, individuals with respiratory conditions such as severe asthma or chronic obstructive pulmonary disease (COPD) may also face heightened risks. The CSR involves hyperventilation and can trigger bronchospasm in susceptible individuals.8

Other medical conditions that increase vulnerability include:

Diabetes: Often associated with impaired circulation and neuropathy, which can affect temperature sensation and thermoregulation.13

Skin Conditions: Diseases like psoriasis or eczema may involve impaired skin barrier function, potentially leading to increased heat loss.13

Raynaud's Disease: Characterized by an exaggerated vascular response to cold, leading to severe constriction of blood vessels in the extremities.20

Autoimmune Disorders: Some autoimmune conditions can affect vascular or neurological function, potentially altering responses to cold.20

Epilepsy: The risk of drowning is significantly elevated if a seizure occurs during immersion.21

B. Other Susceptible Groups (Age, Medications, Pregnancy)

Age is a significant factor influencing vulnerability:

Elderly Individuals: Often experience a decline in their ability to regulate body temperature, may have multiple underlying health conditions (co-morbidities), and are generally at higher risk of hypothermia.13

Children: Have a larger body surface area to mass ratio, leading to more rapid heat loss. Very young children may also have an immature shivering (huttring) response, which is a key mechanism for generating heat.13

Certain medications can interfere with the body's normal response to cold or impair thermoregulation. These include:

Beta-blockers: Commonly prescribed for heart conditions and hypertension, these drugs lower heart rate and can blunt the body's ability to increase cardiac output in response to cold stress.10

Antidepressants: Some classes of antidepressants can affect thermoregulation or autonomic nervous system function.13

Pregnancy is generally considered a contraindication, or at least a situation requiring careful medical consultation before considering CWI, due to potential risks to both mother and fetus.19

Individuals with dementia or other cognitive impairments are also at increased risk due to potential difficulties with orientation, decision-making, and recognizing or responding to the signs of cold stress or hypothermia.13

The common advice to "consult a doctor" before starting CWI is crucial, particularly for these groups.3 However, the effectiveness of this advice hinges on general practitioners possessing specific knowledge about the unique and severe physiological stresses imposed by CWI, including mechanisms like autonomic conflict. A general bill of health might not suffice if these specific stressors are not considered, pointing to a potential need for enhanced education for healthcare providers on this topic.

C. The Influence of Alcohol and Other Substances

The consumption of alcohol significantly amplifies the dangers of CWI. Alcohol impairs judgment, leading to riskier behaviors.13 Physiologically, it causes peripheral vasodilation (widening of blood vessels in the skin), which increases heat loss from the body to the cold environment.13 Critically, alcohol also impairs the shivering response, a primary defense mechanism against hypothermia.13

Alcohol consumption is a well-documented co-factor in many cold-related injuries and deaths, including drownings and fatalities from hypothermia.21 Studies on sauna-related deaths, a practice often culturally linked with subsequent cold plunges in Sweden 3, have also frequently identified alcohol as a contributing factor.22 While some organized CWI groups, such as Umeå Kallbad, explicitly prohibit alcohol during their events 23, the broader cultural association of activities like sauna with social gatherings where alcohol might be consumed creates a high-risk intersection. Even if alcohol is not consumed during the CWI itself, its effects on judgment and physiology can persist, increasing danger if immersion is undertaken while still under its influence or shortly thereafter.

VI. Cold Water Incidents in Sweden: A Statistical Overview

Addressing the incidence of deaths and injuries related to cold water exposure in Sweden is crucial for understanding the potential risks associated with CWI practices. While comprehensive statistics specifically isolating recreational CWI incidents are challenging to obtain, existing data on general cold-related events provide some context.

A. Documented Drownings, Hypothermia Cases, and Cold-Related Fatalities

Several studies and reports offer insights into cold-related incidents in Sweden:

A retrospective analysis of cold-related injury hospital admissions in Northern Sweden between 2000 and 2007 identified 362 cases. These included 244 cases of hypothermia, 105 of frostbite, and 56 outdoor cold-water drowning cases. The average annual incidence for hospitalization due to cold-water drowning in this sub-arctic region was estimated at 0.8 per 100,000 inhabitants. Of the 362 admitted patients, 17 (approximately 5%) died in hospital due to their cold-related injuries. Significant co-factors associated with these incidents included ethanol consumption, dementia, and psychiatric diagnoses 1]. This study primarily reflects accidental exposures rather than elective CWI.

A broader study on unintentional drowning fatalities in Sweden from 2002 to 2021 reported a total of 2,443 such deaths over the period. While there was an overall decline in unintentional drowning rates, the numbers stabilized between 2011 and 2021, with an average of 112 cases per year (an incidence of 1.1 per 100,000 inhabitants) 1]. This comprehensive national study does not specifically differentiate drownings occurring in cold water versus warmer water, nor does it identify incidents linked to recreational CWI practices.

The Svenska Livräddningssällskapet (Swedish Life Saving Society, SLS) regularly compiles and releases drowning statistics. Preliminary data for 2024 indicated that 28 drowning deaths were associated with "bad" (bathing), with 16 of these occurring at unsupervised open-air bathing sites. An additional 2 deaths were related to "is" (ice-related activities).25 In March 2023, the SLS reported 8 drowning fatalities, some of which involved individuals going through ice during activities like skating.26 These figures highlight ongoing risks associated with water and ice activities but do not specifically attribute deaths to organized CWI.

News reports occasionally detail drowning incidents, sometimes occurring in "chilly waters," such as a weekend in May 2012 when five people drowned across Sweden as warm weather drew people to still-cold waters.27 These reports typically describe accidental immersions or rescue attempts rather than incidents during structured CWI.

A study examining sauna-related deaths in Sweden and Finland found an annual death rate from saunas in Sweden to be very low, at 0.06 per 100,000 inhabitants. A significant portion of these rare events involved alcohol consumption or extreme heating followed by rapid cooling conditions.22 This is relevant given the common practice of combining sauna use with cold water plunges.

Culture

A significant challenge in assessing the specific dangers of recreational CWI culture in Sweden is the nature of available statistical data. Existing reports on drownings, hypothermia, or other cold-related injuries typically categorize incidents by general cause (e.g., "drowning," "hypothermia," "bathing accident," "ice accident") but do not routinely differentiate whether the incident occurred during a deliberate, organized, or recreational CWI session as a wellness practice.21 Information from the Swedish Life Saving Society's website also suggests that specific statistics on drownings or deaths directly linked to organized winter bathing ("kallbad") are not readily available in the browsed documentation.28

This data gap is compounded by the physiological mechanisms of some CWI-related deaths. As discussed earlier, fatal cardiac arrhythmias triggered by "autonomic conflict" during CWI are unlikely to be identified as such post-mortem and may be misclassified as simple drownings.11 This means that even if such deaths are occurring within the context of recreational CWI, they would likely not be captured under a specific "CWI-fatality" category.

Therefore, while general cold-water risks are acknowledged, there is a substantial lack of specific epidemiological data in Sweden (and likely internationally) concerning adverse events and fatalities that are unequivocally the result of engaging in recreational CWI as a deliberate practice. This absence of targeted data makes it difficult to precisely quantify the risk level of this growing trend from a purely statistical standpoint, necessitating a greater reliance on understanding the physiological dangers involved. Furthermore, the "belief system" surrounding CWI, which often emphasizes resilience and overcoming challenges, might inadvertently lead to an underreporting of minor or even moderate adverse events by participants who may perceive them as part of the experience or feel hesitant to report them. This potential for underreporting could further obscure the true incidence of non-fatal negative outcomes associated with the practice.

VII. Spotlight on Umeå: Cold Water Immersion Communities and Practices

The city of Umeå in northern Sweden has been identified as a location where cold water immersion communities are actively developing, reflecting the broader national and international trend. Examining the local context provides insights into how this practice is being adopted and managed.

A. The Rise of Communal Cold Bathing in Umeå (e.g., Umeå Kallbad)

A notable initiative in Umeå is the formation of "Umeå Kallbad," an association dedicated to promoting cold bathing and sauna culture.4 This group organizes regular communal events, such as "Söndagsdopp" (Sunday Dips), and has expressed ambitions to develop a permanent, floating sauna and cold bath facility on the Umeälven river.4 Reports indicate growing participation in their events, with attendance sometimes doubling from one weekend to the next, suggesting a strong local interest.5 Umeå Kallbad also offers guided "ice-breaking" experiences for corporate groups and teams, marketing CWI as a unique activity for connection and adventure.6 The stated vision of the group often emphasizes creating a space for personal reflection, connection with nature, community building, and the year-round enjoyment of the local river environment.4

Beyond Umeå Kallbad's activities, other facilities in or near Umeå cater to aspects of cold exposure. For instance, Kvarkenfisk, located at Rovögern fishing village, offers sauna rentals with the option of ice bathing with a sea view.4 While Umelagun is primarily a tempered outdoor summer pool complex 29, the Nordic Wellness Umeå Spa, a commercial fitness center, has announced the installation of Avantopool cold plunge pools, intended to be set at temperatures between 8-10°C, explicitly for "recovery" purposes.30

The emergence of Umeå Kallbad signifies a shift towards a more formalized and community-driven approach to CWI, moving beyond purely individual or informal practices. This organized nature presents both potential opportunities and risks. On one hand, it could facilitate the implementation of standardized safety protocols and provide a supportive environment for participants. On the other hand, rapid growth in participation, if not matched by robust safety infrastructure, adequate participant education on risks, and sufficiently trained oversight, could inadvertently increase the exposure of individuals, particularly novices, to the hazards of CWI.

B. Safety Protocols: Medical Screening, Supervision, and Emergency Preparedness

The user query specifically raises the question of whether participants in Umeå's CWI communities undergo medical checkups. Umeå Kallbad states on its event pages (for "Söndagsdopp" and a "New Year's Day Dopp") that "Guides will be present to ensure everyone's safety" and advises attendees to "Make sure to check out our Safety Guidelines before attending".31 However, the detailed content of these specific "Safety Guidelines" was not found within the provided documentation from their website 31, and a direct link to a dedicated safety page (umeakallbad.se/sakerhet) was reported as inaccessible during the research phase.33 The FAQ section of their website does mention that alcohol is not permitted in the sauna for safety reasons 14].

General safety tips for CWI are provided by Visit Umeå, an entity whose website mentions Umeå Kallbad's vision. These tips include never bathing alone, checking ice conditions, using calm and controlled breathing, keeping initial dips short for beginners, warming up properly afterward, and avoiding an immediate hot shower.4

Concerning medical pre-screening, while general advice from various sources (e.g., insurance companies, retailers, and some municipal advice echoing lifesaving societies) strongly recommends that individuals with pre-existing health conditions, those on medication, or anyone uncertain about their health should consult a doctor before engaging in CWI 3, there is no explicit statement in the available materials from Umeå Kallbad 5 indicating a mandatory requirement for medical checkups or formal pre-activity health screening for all participants. This is noteworthy, as international guidelines, such as those proposed by AUSactive (an Australian fitness industry body), do recommend pre-activity screening to identify contraindications or underlying health conditions that might elevate risk during CWI.20 The welcoming stance towards first-timers at Umeå Kallbad events 31, while inclusive, underscores the importance of robust safety measures and clear communication of risks, especially for those new to the practice. The lack of readily accessible, detailed safety guidelines and an unclear policy on medical pre-screening for all participants in the provided information is a point of concern, particularly given the potential for severe adverse events in individuals with undiagnosed conditions. While the presence of "guides" is a positive step, their specific level of medical, first aid, or cold water rescue training is not specified in the available documents.

The introduction of cold plunge pools at commercial facilities like the Nordic Wellness Umeå Spa, set at temperatures (8-10°C) well within the range known to induce cold shock 9, also brings to the forefront the need for clarity regarding their specific safety protocols, user screening procedures, supervision levels, and emergency preparedness plans.

C. Local Perceptions and the "Therapy Belief System"

Interactions with participants and proponents of CWI in Umeå, as reported in local media, reveal a strong belief in its multifaceted benefits. Descriptions of the experience often highlight a profound sense of being present, achieving calmness, experiencing joy and happiness, building mental strength, and fostering a sense of community.4 CWI is frequently characterized as a "physical, mental, and inner experience".4 The language used—such as "brinner för att bada kallt" (being passionate about cold bathing), experiencing an "endorfin-kick" (endorphin rush), and finding it a "meditativ stund" (meditative moment)—indicates a deeply positive perception and conviction regarding its effects.4

This enthusiastic embrace and the strong communal aspect of CWI in Umeå can be powerful motivators for participation and adherence to the practice. However, such an environment, if not carefully balanced with comprehensive risk education, also has the potential to inadvertently downplay the inherent dangers. The positive framing and group dynamic might, in some instances, lead to peer pressure (overt or subtle) or a reluctance among individuals to acknowledge negative experiences, discontinue an immersion if feeling unwell, or express concerns, particularly if the prevailing group norm is one of enthusiastic endurance and "overcoming the challenge." This dynamic can reinforce the "therapy belief system," where the focus remains predominantly on the anticipated benefits, potentially overshadowing a thorough consideration of the significant risks involved.

VIII. Navigating the Chill: Current Safety Guidelines and Official Stances in Sweden

Given the potential dangers of CWI, the availability and nature of safety guidelines from public health services, lifesaving organizations, and national health authorities in Sweden are of paramount importance.

A. Recommendations from Public Health Services (e.g., 1177 Vårdguiden) and Lifesaving Societies (e.g., Svenska Livräddningssällskapet)

1177 Vårdguiden, the Swedish national healthcare advisory service, provides information on the risks of cold exposure. It warns about hypothermia and identifies vulnerable groups, including children, the elderly, individuals consuming alcohol, and those with certain medical conditions (e.g., diabetes) or taking specific medications (e.g., beta-blockers).13 An article by Kry, a digital healthcare provider often linked in the 1177 context, acknowledges that CWI can trigger the body's fight-or-flight response, release noradrenaline and adrenaline, potentially lower blood pressure, and increase brown fat. However, it also states that research on benefits is mixed and advises individuals with cardiovascular disease or high blood pressure to consult a doctor before engaging in CWI. Crucially, it recommends never to "kallbada" (cold bathe) alone or for excessively long periods.15

The Svenska Livräddningssällskapet (SLS), the Swedish Life Saving Society, is a key organization for water safety. While it provides general water safety ("Badvett") and ice safety ("Isvett") guidelines 28, specific, detailed national guidelines solely focused on recreational CWI as a wellness practice are not prominently featured in the provided documentation. However, advice from Swedish municipalities, such as Motala Kommun, often references SLS principles when discussing winter bathing. Motala Kommun advises individuals with high blood pressure or heart disease to consult a doctor before winter bathing, to start gradually with short immersions (e.g., 5–20 seconds), to avoid dipping the head as a beginner, to use a ladder for safe entry and exit, and never to bathe alone or if alcohol-impaired.35 Karlstad Kommun offers similar guidance.36

Issakerhet.se, a collaborative ice safety website involving SLS and other organizations, also provides guidelines relevant to winter activities, including winter bathing, emphasizing preparedness, knowledge of ice conditions, and the importance of company 28, though specific detailed guidelines for winter bathing from this source were inaccessible during research.37 Insurance companies like Trygg-Hansa also disseminate safety advice, reiterating the need for medical consultation for those with high blood pressure or heart disease, ensuring one is fully healthy (no infections or colds), and avoiding alcohol. They advise having company, using warm clothing post-immersion, entering the water gently, and employing controlled breathing techniques. They also note that research on CWI benefits is divided and that the practice constitutes a significant physiological stressor.18

While this collective advice offers valuable common-sense precautions for any activity in cold environments, there appears to be a lack of specific, national-level, detailed clinical guidelines from primary health authorities that are explicitly tailored to the unique and potentially severe physiological stresses of recreational CWI undertaken as a purported therapy. Much of the existing advice addresses general cold weather safety rather than the nuances of elective, repeated cold immersions.

B. Guidance from Municipalities and Other Advisory Bodies

As noted, individual municipalities like Motala 35 and Karlstad 36 provide safety tips for winter bathing, often aligning with or drawing from SLS recommendations. Tourism-related entities, such as Visit Umeå, also offer basic safety advice for those interested in local CWI opportunities.4

Commercial entities, like the outdoor retailer Naturkompaniet, provide guidance to customers interested in winter bathing. Their advice includes seeking medical consultation for individuals with cardiovascular disease or during pregnancy, starting acclimatization with cold showers, always having company, using appropriate warm gear (like hats and gloves, as extremities lose heat fast), and avoiding head immersion for beginners.19

Critically, Idrottsforskning.se, a platform associated with Karolinska Institutet that discusses sports science research, has highlighted findings that CWI can actually impair muscle recovery and adaptation processes in athletes, which contrasts sharply with its popular use for enhancing athletic recovery.17 This underscores the gap between perceived benefits and scientific findings in some areas.

The dissemination of safety information related to CWI in Sweden appears to be somewhat fragmented. It relies on a combination of local authorities, non-governmental organizations like SLS, commercial retailers, and specific interest websites, rather than a unified, prominent public health campaign from a central national agency. This fragmentation could lead to inconsistencies in messaging or varying levels of risk awareness among different CWI practitioners across the country.

C. Position of National Health Authorities (Folkhälsomyndigheten, Socialstyrelsen) on Recreational CWI

A key aspect of assessing the danger level of CWI in Sweden involves understanding the official stance and guidance, if any, from the country's principal national health authorities: Folkhälsomyndigheten (The Public Health Agency of Sweden) and Socialstyrelsen (The National Board of Health and Welfare).

Based on the available research materials, there is no clear evidence that Folkhälsomyndigheten has issued specific, comprehensive guidelines or risk assessments for recreational cold water immersion or winter bathing as a wellness practice.17 While the agency addresses various public health issues, elective CWI does not appear to be a current focus of specific public guidance.

Similarly, Socialstyrelsen's most relevant identified document is a report from 2003 (an update of a 1996 version) titled "Hypotermi, Kylskador, Drunkningstillbud i kallt vatten" (Hypothermia, Cold Injuries, Drowning Incidents in Cold Water) 14]. This extensive report focuses on the epidemiology, pathophysiology, and treatment of accidental hypothermia and cold injuries, as well as near-drowning in cold water. It defines stages of hypothermia and identifies vulnerable groups in the context of unplanned cold exposure. However, it does not specifically address the risks or safety prerequisites for individuals voluntarily engaging in repeated CWI for health or recreational purposes. Other search results did not yield direct guidelines from Socialstyrelsen on this specific topic.43

The apparent absence of specific, current, and detailed guidelines or risk assessments from Sweden's main national health authorities dedicated to recreational CWI is a significant observation. Their existing materials tend to focus on accidental cold exposure and its medical management. This void in official guidance tailored to the elective practice of CWI may contribute to an environment where the "therapy belief system" can grow with less authoritative counter-messaging regarding the potential risks and necessary precautions.

IX. Assessing the Overall Danger: A Risk Analysis of the CWI Therapy Belief System

The rise of cold water immersion as a purported therapy warrants a careful risk analysis, particularly concerning the "CWI therapy belief system"—a framework of understanding that often emphasizes broad health benefits while potentially underrepresenting significant dangers.

The core of this belief system is the assertion that CWI offers a wide array of positive outcomes, including improved mood, enhanced immunity, reduced inflammation, boosted metabolism, and accelerated recovery from exercise.1 However, as detailed extensively in this report, the scientific evidence underpinning many of these claims is often weak, inconclusive, derived from studies with methodological limitations, or reliant on subjective self-reports.1 In some cases, the purported benefits are directly contradicted by scientific findings; for example, CWI can impair long-term muscle adaptation after exercise 1, and it acutely increases inflammatory markers rather than universally reducing inflammation.1

In stark contrast to the often-tenuous evidence for benefits, the physiological risks associated with CWI are well-documented, acute, and potentially severe. These include the immediate dangers of the Cold Shock Response leading to involuntary gasping and drowning; "autonomic conflict" triggering cardiac arrhythmias and potentially sudden death; significant cardiovascular strain (especially perilous for individuals with underlying heart conditions, diagnosed or undiagnosed); progressive hypothermia with cognitive and physical impairment; and the risk of Non-Freezing Cold Injuries leading to chronic pain and sensitivity.7

The primary danger inherent in the "CWI therapy belief system" lies in its potential to systematically overstate unproven or weakly supported benefits while simultaneously understating, ignoring, or downplaying these severe, scientifically validated risks. This imbalance can mislead individuals, encouraging those who are unprepared, unsuitable, or unaware of their own vulnerabilities to engage in a hazardous activity under the guise of self-improvement or therapy. The "one size fits all" approach often implicitly promoted by this belief system fails to account for significant individual variability in physiological responses to cold and largely overlooks crucial contraindications.7

While safety advice accompanying CWI promotion often includes a general recommendation to "consult a doctor," the effectiveness of this relies on individuals recognizing their potential risk factors and, critically, on healthcare providers possessing specific knowledge about the unique stresses of CWI. A general practitioner might clear an individual based on overall health without fully appreciating the extreme cardiovascular and autonomic challenges that CWI can impose, particularly on someone with an asymptomatic underlying condition.

The social and communal aspects of CWI, such as those observed in Umeå 4, while offering positive elements like support and shared experience, can also inadvertently amplify the "belief system." Group enthusiasm and a focus on overcoming challenges might create an environment where individual concerns are minimized, or where participants feel subtle pressure to endure discomfort beyond safe limits. This can make it more difficult for individuals to listen to their own bodies or to report negative experiences if the prevailing group narrative is overwhelmingly positive.

Furthermore, the current landscape appears to lack specific regulatory oversight or standardized safety certifications for CWI practitioners or facilities that promote CWI explicitly as a "therapy." Unlike established medical treatments or even many fitness industry certifications, the promotion and practice of CWI for therapeutic purposes often occur with few formal checks and balances. This relative lack of regulation, combined with the often-weak evidence base for therapeutic claims and the well-documented risks, creates an environment where the "CWI therapy belief system" can propagate with potentially dangerous consequences for public health. Efforts by some industry bodies, like AUSactive's proposed guidelines 20, represent steps towards standardization, but these are not yet universally adopted or government-mandated.

X. Conclusion and Strategic Recommendations

The practice of Cold Water Immersion (CWI), including its cultural manifestation as "kallbad" in Sweden, presents a complex interplay of perceived benefits and scientifically documented dangers. While embraced by many for its invigorating effects and purported health advantages, a thorough examination of evidence reveals significant risks that demand careful consideration and proactive safety measures. The "CWI therapy belief system," which often promotes widespread benefits with insufficient scientific backing, can inadvertently lead individuals to underestimate these perils.

A. Key Findings on the Dangers of Cold Water Immersion

This report has identified several critical aspects regarding the dangers of CWI:

Acute Physiological Dangers: CWI triggers immediate and potentially life-threatening responses, including the Cold Shock Response (CSR) with associated drowning risk, "autonomic conflict" leading to cardiac arrhythmias and possible sudden death, significant cardiovascular strain, and rapid onset of hypothermia. Non-Freezing Cold Injuries (NFCIs) pose a risk of chronic pain and sensitivity.

Evidence Discrepancy: There is a notable gap between the widely touted health benefits of CWI and the strength of supporting scientific evidence. Many claims lack robust validation from high-quality, large-scale randomized controlled trials, and some are contradicted by research (e.g., impairment of muscle adaptation, acute pro-inflammatory response).

Vulnerable Populations: Individuals with pre-existing medical conditions (especially cardiovascular), the elderly, children, those on certain medications, and individuals under the influence of alcohol are at substantially increased risk of severe adverse events. Undiagnosed conditions, particularly cardiovascular, represent a hidden vulnerability.

Data Gaps in Sweden: While general statistics on cold-related incidents and drownings exist, there is a lack of specific data tracking adverse events or fatalities directly attributable to the practice of recreational CWI. This makes precise epidemiological risk assessment for this specific activity challenging.

The "Therapy Belief System": The promotion of CWI as a broad therapeutic intervention, often without adequate emphasis on risks and contraindications, poses a public health concern by potentially encouraging unsafe practices.

B. Recommendations for Individuals Engaging in CWI

Individuals considering or practicing CWI should prioritize safety through informed and cautious participation:

Medical Pre-Screening: Undertake a thorough medical evaluation with a healthcare provider, ideally one informed about the physiological stresses of CWI, before initiating the practice. This is especially critical for individuals over 40, those with any known health concerns (however minor), a family history of heart conditions, or those taking regular medication.

Gradual Acclimatization: Begin with shorter immersion durations in less cold water and gradually increase exposure only if no adverse effects are experienced. Avoid progressing too quickly.

Never Immerse Alone: Always have a knowledgeable and responsible companion present who understands the risks and can provide assistance or summon help. In open water settings, ensure reliable supervision.

Know the Risks and Personal Limits: Educate oneself about the Cold Shock Response, signs of hypothermia, and other potential dangers. Be acutely aware of one's own body's signals and exit the water immediately if feeling unwell, excessively cold, dizzy, or experiencing chest pain/palpitations, regardless of group behavior or personal goals.

Controlled Entry and Breathing: Enter the water slowly and deliberately to minimize the intensity of the cold shock. Avoid jumping or diving in, especially for beginners. Practice calm, controlled breathing to manage the initial gasp reflex and hyperventilation. Do not hyperventilate before immersion.

Limit Exposure Time: Keep immersions brief, particularly for novices (e.g., 30 seconds to 2 minutes, depending on water temperature and individual tolerance). Duration should be guided by safety, not endurance.

Avoid Head Immersion Initially/If Inexperienced: Submerging the head can intensify the diving response and autonomic conflict. Beginners should keep their heads out of the water.

No Alcohol or Recreational Drugs: Absolutely avoid consuming alcohol or recreational drugs before or during CWI, as they impair judgment, thermoregulation, and physiological responses.

Proper and Prompt Rewarming: Have warm, dry clothes, a hat, gloves, and shelter readily available. Change out of wet attire immediately. Consume a warm, non-alcoholic beverage. Allow the body to rewarm gradually; avoid excessively hot showers or baths immediately after exiting very cold water, as this can sometimes cause complications.

Consider Flotation Aids: When immersing in open water, the use of a personal flotation device (PFD) can be a valuable safety measure, especially if swimming ability is limited or conditions are uncertain.

C. Recommendations for Organizers of CWI Activities (especially in Umeå)

Organizers of group CWI events, including community groups like Umeå Kallbad and commercial facilities, bear a significant responsibility for participant safety:

Mandatory Safety Briefings: Conduct comprehensive safety briefings for all participants prior to immersion, clearly outlining the potential risks, signs of adverse reactions, safe immersion procedures, and emergency action plans.

Medical Screening and Waivers: Implement a robust system for pre-activity health screening. This could involve a tailored Physical Activity Readiness Questionnaire (PAR-Q+) that includes specific questions about conditions contraindicated for CWI. Require medical clearance for individuals identified as high-risk. Clearly display and communicate all contraindications. Participants should sign informed consent waivers that explicitly detail the risks.

Trained Supervision: Ensure that all CWI sessions are supervised by personnel trained in first aid, CPR, cold water rescue techniques, and the recognition and initial management of CWI-specific emergencies (e.g., severe CSR, hypothermia, signs of cardiac distress).

Emergency Equipment and Plan: Maintain readily accessible emergency equipment, including PFDs, rescue lines or poles, thermal blankets, a first aid kit, and ideally an Automated External Defibrillator (AED). Have a clear, practiced emergency action plan that includes communication protocols with local emergency medical services.

Controlled Access and Environment: Provide safe and easy entry and exit points (e.g., ladders, gently sloping access). If on ice, ensure ice thickness is regularly checked and verified as safe. Be aware of and mitigate risks from water currents or other environmental hazards.

Promote Realistic Expectations and Risk Awareness: Avoid overstating unproven benefits. Focus on providing a safe experience and clearly communicate the known risks and contraindications. Discourage competitive or endurance-focused behavior.

Publish Detailed and Accessible Safety Guidelines: Develop comprehensive safety guidelines and make them easily available to all potential participants (e.g., on websites, at registration). These should detail risks, contraindications, what to expect, what to bring, and emergency procedures.

D. Recommendations for Public Health Authorities and Future Research

Addressing the public health implications of CWI requires action at a broader level:

Develop and Disseminate Official Guidelines: National health authorities in Sweden (e.g., Folkhälsomyndigheten, Socialstyrelsen) should collaborate to develop and widely disseminate clear, evidence-based public health guidelines on the risks, contraindications, and safe practices associated with recreational CWI. These guidelines should be distinct from advice on accidental cold exposure and specifically address the elective nature of this practice.

Improve Data Collection and Surveillance: Implement or enhance systems for tracking adverse events, injuries, and fatalities specifically related to recreational CWI. This data is crucial for understanding the true public health impact of the trend and for informing targeted prevention strategies.

Fund High-Quality Research: Prioritize and fund methodologically rigorous research, including large-scale RCTs, to definitively evaluate the short-term and long-term health effects (both positive and negative) of various CWI protocols on diverse populations. Research should also focus on identifying reliable markers for individual susceptibility to CWI-related harm.

Educate Healthcare Professionals: Develop and disseminate educational materials for general practitioners and other relevant healthcare professionals to ensure they are well-informed about the specific physiological stresses, risks, and contraindications of CWI. This will enable them to provide more accurate and tailored advice to patients considering or engaging in the practice.

By adopting a more cautious, evidence-informed, and safety-conscious approach, individuals, communities, and public health bodies can work together to mitigate the dangers associated with the growing trend of cold water immersion.

Works cited

1. journals.plos.org, accessed June 4, 2025, https://journals.plos.org/plosone/article/file?type=printable&id=10.1371/journal.pone.0317615
2. Jumping into the Ice Bath Trend! Mental Health Benefits of Cold Water Immersion | Cognitive Enhancement - Stanford Center on Longevity, accessed June 4, 2025, https://longevity.stanford.edu/lifestyle/2024/05/22/jumping-into-the-ice-bath-trend-mental-health-benefits-of-cold-water-immersion/
3. Ice bath: The Health Trend from Sweden and Finland - scandi, accessed June 4, 2025, https://www.scandi.co.uk/lifestyle/ice-bath/
4. Vinterbada i Umeå, tips och inspiration till ditt nästa kallbad | Visit Umeå, accessed June 4, 2025, https://visitumea.se/sv/kallbad-i-umea
5. De brinner för att bada kallt – vill bygga anläggning i Umeälven - SVT Nyheter, accessed June 4, 2025, https://www.svt.se/nyheter/lokalt/vasterbotten/de-brinner-for-att-bada-kallt-vill-bygga-anlaggning-i-umealven
6. Booking - Umeå Kallbad, accessed June 4, 2025, https://www.umeakallbad.se/sauna-bookings
7. What are the Risks and Benefits of a Cold Plunge? | The Scientist, accessed June 4, 2025, https://www.the-scientist.com/what-are-the-risks-and-benefits-of-a-cold-plunge-72969
8. Habituation of the cold shock response: A systematic review and meta-analysis - PubMed, accessed June 4, 2025, https://pubmed.ncbi.nlm.nih.gov/38211547/
9. Cold Water Hazards and Safety - National Weather Service, accessed June 4, 2025, https://www.weather.gov/safety/coldwater
10. You're not a polar bear: The plunge into cold water comes with risks ..., accessed June 4, 2025, https://www.heart.org/en/news/2022/12/09/youre-not-a-polar-bear-the-plunge-into-cold-water-comes-with-risks
11. 'Autonomic conflict': a different way to die during cold water ..., accessed June 4, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC3459038/
12. Cardiovascular diseases, cold exposure and exercise - PMC, accessed June 4, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC6204981/
13. Så gör du vid nedkylning - 1177, accessed June 4, 2025, https://www.1177.se/Vastra-Gotaland/olyckor--skador/akuta-rad---forsta-hjalpen/sa-gor-du-vid-nedkylning/
14. Hypotermi, Kylskador, Drunkningstillbud i kallt vatten - Socialstyrelsen, accessed June 4, 2025, https://www.socialstyrelsen.se/globalassets/sharepoint-dokument/artikelkatalog/ovrigt/2003-123-6.pdf
15. Kallbad – bra eller dåligt enligt forskningen? - Kry, accessed June 4, 2025, https://www.kry.se/din-halsa/kallbad-bra-eller-daligt-enligt-forskningen/
16. Effects of cold-water immersion on health and wellbeing: A systematic review and meta-analysis - PubMed, accessed June 4, 2025, https://pubmed.ncbi.nlm.nih.gov/39879231/
17. Kyla försämrar återhämtningen - Idrottsforskning.se, accessed June 4, 2025, https://www.idrottsforskning.se/kyla-forsamrar-aterhamtningen/
18. Kallbad - se våra tips för säkrare vinterbad - Familjen Trygg-Hansa, accessed June 4, 2025, https://familjen.trygghansa.se/vatten-simning/vatten-sakerhet/kallbada
19. Vinterbad & kallbad | Tips & råd - Naturkompaniet, accessed June 4, 2025, https://www.naturkompaniet.se/kunskap/halsa/vinterbad/
20. New guidelines for safe cold water immersion therapy - Spa Life International, accessed June 4, 2025, https://www.spa-life.international/news/article/new-guidelines-for-safe-cold-water-immersion-therapy/
21. Accidental cold-related injury leading to hospitalization in northern Sweden: an eight-year retrospective analysis - PubMed Central, accessed June 4, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC4016575/
22. Death in Sauna* - ResearchGate, accessed June 4, 2025, https://www.researchgate.net/publication/5380849_Death_in_Sauna
23. FAQ - Umeå Kallbad, accessed June 4, 2025, https://www.umeakallbad.se/faq
24. Unintentional drowning fatalities in Sweden between 2002 and 2021 - PMC, accessed June 4, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC11568521/
25. Antalet omkomna vid drunkning ökade under 2024 | Svenska Livräddningssällskapet, accessed June 4, 2025, https://www.mynewsdesk.com/se/svenska_livraddningssallskapet/pressreleases/antalet-omkomna-vid-drunkning-oekade-under-2024-3371737
26. Oroande tendens, fler som omkommer i badanläggningar. Hur stänger vi glappet för att minska antalet drunkningar? - Svenska Livräddningssällskapet, accessed June 4, 2025, https://svenskalivraddningssallskapet.se/oroande-tendens-fler-som-omkommer-i-badanlaggningar-hur-stanger-vi-glappet-for-att-minska-antalet-drunkningar/
27. Deadly weekend claims five at Swedish beaches - The Local Sweden, accessed June 4, 2025, https://www.thelocal.se/20120528/41076
28. Svenska Livräddningssällskapet: Hem, accessed June 4, 2025, https://svenskalivraddningssallskapet.se/
29. Umelagun - Umeå kommun, accessed June 4, 2025, https://www.umea.se/upplevaochgora/idrottmotionochfriluftsliv/simhallarbadhusutebassanger/umelagun.4.27a2de8b172da059ace1c6a.html
30. Umeå Spa - Nordic Wellness, accessed June 4, 2025, https://nordicwellness.se/vara-klubbar/umea/umea-spa/
31. Söndagsdopp - Umeå Kallbad, accessed June 4, 2025, https://www.umeakallbad.se/sondagsdopp
32. Söndagsdopp - Umeå Kallbad, accessed June 4, 2025, https://www.umeakallbad.se/nyd25
33. accessed January 1, 1970, https://www.umeakallbad.se/sakerhet
34. Tips till nybörjaren: Tänk på det här om du ska testa kallbad - Go Active Travel, accessed June 4, 2025, https://www.goactivetravel.se/resebloggen/tips-till-nyborjaren-tank-pa-det-har-om-du-ska-testa-kallbad
35. Bada säkert - Motala kommun, accessed June 4, 2025, https://www.motala.se/uppleva-och-gora/friluftsliv-och-motion/badplatser/bada-sakert/
36. Vattensäkerhet - Karlstads kommun, accessed June 4, 2025, https://karlstad.se/uppleva-och-gora/friluftsliv-och-motion/vattensakerhet
37. accessed January 1, 1970, https://www.issakerhet.se/vinterbad/
38. accessed January 1, 1970, https://www.folkhalsomyndigheten.se/
39. Rörelse och hälsa - hur mycket krävs egentligen? - Svensk Hälsokost, accessed June 4, 2025, https://www.svenskhalsokost.se/rorelse-och-halsa-hur-mycket-kravs-egentligen
40. SKOLBAD I SVERIGE - DiVA portal, accessed June 4, 2025, https://www.diva-portal.org/smash/get/diva2:1715976/FULLTEXT01.pdf
41. Food Pharmacy-podden | Lyssna nu, accessed June 4, 2025, https://foodpharmacy.se/podd/
42. Umeå Kallbad: Home, accessed June 4, 2025, https://www.umeakallbad.se/
43. accessed January 1, 1970, https://www.socialstyrelsen.se/
44. Anhörigstöd våren 2025 - Orust kommun, accessed June 4, 2025, https://www.orust.se/download/18.41647cc19540b9d03b38fd9/1741339794045/Anh%C3%B6rigst%C3%B6dsprogram%20v%C3%A5ren%202025.pdf
45. Barns miljöer för fysisk aktivitet - CABI Digital Library, accessed June 4, 2025, https://www.cabidigitallibrary.org/doi/pdf/10.5555/20103099725