After the sauna, everyone into the freezing water: but is the cold plunge truly beneficial?

There is something almost hypnotic in the images that have conquered the wellness world in recent years: a person exits a sauna, approaches a tub full of ice water, takes a deep breath, and submerges.

The cold plunge has become one of the symbols of the new wellness culture. It has entered Spas, resorts, recovery centers, and even the daily routines of those seeking a quick way to feel more energetic.

The message that often accompanies this practice is simple: cold is a stressor for the body, and for that very reason, it is said to make it stronger.

But there is a problem.

We do not have sufficient evidence to say that more cold means more benefit.

On the contrary, the most recent research invites us to be much more cautious. Exposure to cold water certainly produces an intense and measurable physiological response. However, a bodily response does not automatically equate to a health benefit. And the effects observed in studies depend on the temperature, duration, frequency of exposure, the individual’s characteristics, and, above all, the goal one wishes to achieve.

It is an important distinction, because in contemporary wellness, the feeling of having done something “extreme” can easily be confused with the idea that such behavior is necessarily healthy.

The body does not interpret the cold as pampering

When a person suddenly enters cold water, the first phenomenon that manifests is not relaxation.

It is an alert response.

Immersion causes what physiology defines as the cold shock response, a rapid reaction of the autonomic nervous system characterized, among other things, by an increase in ventilation and heart rate, and significant changes in peripheral circulation.

It is a defensive reaction: the body perceives a sudden loss of heat and immediately tries to adapt.

A systematic review and meta-analysis published in 2024 analyzed precisely the adaptation to the cold shock response. The review included 17 study groups and found that repeated exposures can attenuate some components of the response, including respiratory rate and heart rate. But this is physiological habituation to the stimulus, not proof that cold immersion automatically produces an improvement in general health.

The difference is not subtle: the body can learn to react less intensely to a stimulus without that stimulus becoming necessary or therapeutic.

This is one of the reasons why the cold plunge deserves to be described with greater precision.

What research really says about the benefits

The appeal of the practice also stems from some interesting scientific observations.

A systematic review and meta-analysis published in 2025 examined 11 randomized trials involving a total of 3,177 healthy adults subjected to cold water immersion. The studies used water between 7 and 15 °C and very different durations, from 30 seconds up to two hours.

The results are far from being reducible to a slogan.

The review found, in particular, a reduction in stress measured 12 hours after immersion, but not immediately after, nor at one, 24, or 48 hours. No significant effects on immune function emerged in the moments immediately following exposure. The authors also emphasized that the number of available studies is still limited and that higher-quality trials are needed to clarify long-term effects.

The outlook became even more cautious in 2026.

A new systematic review and meta-analysis published in Frontiers in Physiology examined 13 studies and 4,105 participants, evaluating the effects of cold water exposure on depression, perceived stress, well-being, mood, and other psychological parameters.

The authors observed that some results seem to point toward a possible benefit, but the confidence intervals are wide and the effects tend to diminish when only controlled analyses are considered. Furthermore, most studies present a high, serious, or critical risk of bias.

The conclusion is therefore much more interesting than a simple “it works” or “it doesn’t work”: current evidence does not yet allow us to establish that cold water exposure reliably improves mood, depressive symptoms, perceived stress, or well-being.

For a practice that is often presented as one of the great longevity strategies, this is a fact that deserves to be known.

Cold can be useful, but it depends on the question

One of the reasons the debate on the cold plunge has become confused is that practices with completely different objectives are placed under the same label.

An athlete using cold immersion after a competition is not necessarily seeking the same thing as a person who enters a cold tub in the morning because they want to feel more alert.

In the first case, we are talking about exercise recovery. In the second, a possible wellness strategy.

The literature on cold immersion in sports recovery is more developed. A systematic review published in 2025 examined the effects of cold immersion on heart rate variability after exercise and found signs of parasympathetic reactivation in all included studies, although only a portion of the results was statistically significant compared to passive recovery.

This does not mean that the cold plunge is indispensable for those who train.

It means that a specific scientific question exists, for which specific data exists.

It is a very different approach from turning cold water immersion into a universal therapy for metabolism, immunity, longevity, depression, energy, and performance.

When a single practice promises to improve practically everything, it is generally the right time to slow down and look at the evidence.

The point that wellness tends to forget: cold has a physiological cost

There is also an aspect that deserves particular attention in Spas: cold water is not simply “toning” water. It is a significant physiological stimulus.

The American Heart Association has emphasized that sudden exposure to cold can cause a rapid increase in breathing, heart rate, and blood pressure. For people with certain cardiovascular conditions, the acute stress caused by the cold can be particularly significant.

The CDC also considers cold water immersion a situation in which body cooling can be very rapid. The cold shock response can appear within the first few minutes and, with prolonged exposure, hypothermia can develop.

For this reason, the cold plunge should not be proposed as a test of strength. And above all, it should not become a competition.

The person who lasts the longest has not necessarily obtained a greater benefit.

This is perhaps the least spectacular part of the practice, but also the one most consistent with a serious conception of wellness: well-being is not measured by the amount of discomfort we have managed to endure.

From challenge to ritual: the true evolution could be this

Perhaps the future of the cold plunge will not consist of increasingly colder tubs. In fact, it could be exactly the opposite.

As research becomes more precise, interest could shift from the question “how much cold can I endure?” to much more sensible questions: for what goal am I using the cold? How intense is the stimulus? How does my body react? Is it appropriate for me? What does the literature really say about the effect I am seeking?

It is a transition that concerns the entire wellness sector. For years, well-being has been described through the logic of intensity: hotter, colder, longer, harder.

But physiology does not necessarily follow this logic: an effective stimulus is not by definition an extreme stimulus. And an intense experience is not by definition a healthy experience.

The cold plunge can be an interesting practice. It can have specific applications, especially in the field of physical recovery management, and research continues to study its effects.

But in 2026, the most scientifically correct answer to the question “is it truly beneficial?” is not an absolute yes.

It is: it depends on what we mean by beneficial, who practices it, how it is practiced, and what result we are trying to achieve.

Verified scientific sources:

• Schepanski SN et al., 2026, Cold-Water Exposure and Psychological Outcomes in Adults: A Systematic Review and Meta-Analysis, Frontiers in Physiology: 13 studies, 4,105 participants; cautious conclusion on the psychological efficacy of cold-water exposure.
• Cain T et al., 2025, Effects of cold-water immersion on health and wellbeing: A systematic review and meta-analysis, PLOS ONE: 11 randomized trials, 3,177 participants.
• Tipton MJ et al., 2024, Habituation of the cold shock response: A systematic review and meta-analysis: data on physiological adaptation to cold shock.
• American Heart Association, information on the cardiovascular risks of sudden cold water immersion and, more recently, the 2026 scientific statement on the cardiovascular effects of non-optimal temperatures.
• CDC Yellow Book, guidelines on the risks of cold water immersion and hypothermia.