Ice bath enthusiasts? The critical danger you don’t know about — and who is most exposed to it

Three weeks ago, the phone rang. Lital (pseudonym), a former patient and currently my most athletic friend, was on the line. “Ilana… can you help me? Please… tell me I’m not going to die,” she said in a slow, heavy voice.

She told me about an ice bath she had done three days earlier. Just one minute and twenty seconds in the freezing water, and boom: “Within a second I felt as if an axe was splitting my head.” Despite being left with a dull headache, she tried to return to routine, but during a Pilates class three days after the ice immersion, the “axe” struck again at the crown of her head, in exactly the same spot.

After I asked her to pull over to the side of the road and posed another series of questions to understand the unfolding event, it was clear to me that this was an urgent medical emergency. I consulted Gemini (AI) and another engine for extra reassurance, and the answer: There was RCVS — Reversible Cerebral Vasoconstriction Syndrome — reversible constriction of the cerebral blood vessels.

Knowing Lital (a hospital refuser), I tried to bargain with the robot, but Gemini insisted: “Doctor, she must receive treatment with calcium channel blockers to dilate cerebral blood vessels under supervision, and this is given only in a hospital. ER and now!”

Lital, after two Optalgin tablets and some relief of the pain, insisted that “it will be fine and there’s no need for a hospital,” but after Gemini provided me with a list of possible complications (from ischemic stroke to cerebral hemorrhage) and I sent them to her on WhatsApp, she began her way to Ichilov.

If there are sometimes small miracles, they happened that evening. The ER physician agreed to read my assertive referral letter carefully and immediately consulted the on-call neurologist, who sent Lital for the necessary test. CTA is imaging of the cerebral blood vessels, which is not usually done in the ER setting. In a regular CT, you don’t see anything. Lital was hospitalized for 5 days, and was discharged to a recovery leave at home for another 6 weeks, during which she is forbidden to exert herself.

But the story is much bigger than Lital’s case. Ice baths are the hottest (or coldest) trend right now. They promise mountains and hills of health, but what the trend’s devotees don’t tell you is that most of the physiological studies of cold therapy were conducted on men, usually soldiers or young athletes. Women, surprisingly, are not “small men.” The physiology is different, especially around menopause.

The main risk group for RCVS is women aged 44 to 60. The hormonal changes at this age make their blood vessels much more sensitive to fluctuations of adrenaline and stress. When a woman in this age group jumps into icy water, she is performing a “live vascular experiment” on her brain.

As of today, there are still no organized studies on the connection between ice baths and this syndrome. What exists are mainly “case reports” that are accumulating in neurology departments in Israel and around the world.

Lital’s ice bath instructor did not identify the phenomenon at the time it occurred, and probably did not know about this risk. Most primary physicians have not encountered it either. But it is important that you know: RCVS can occur not only with ice, but also in other situations of “stress” to the vascular system: Sex (orgasmic headache), straining on the toilet, massive vomiting, cannabis (very common!), and even simple cold medications containing pseudoephedrine.

A search of the professional medical literature reveals case reports of women who arrived at ERs with “thunderclap headache” after ice immersion. Science is beginning to catch up with the trend, and the data show that the mechanism intended to protect us from the cold — vasoconstriction — becomes, in some women, a dangerous trap inside the brain.

Dear women and dear scientists, sometimes science lags behind the trend. Before you jump into ice because “everyone is doing it and it’s healthy,” remember that different physiological rules apply to you.