As record-breaking heatwaves grip much of Europe, we came across a widely shared Instagram post by Pubity, a meme page with over 42 million followers captioned “I know everyone in the UK could use these right now”, advising readers to “skip the ice water because a hot drink cools you faster”. The post claims that in dry conditions, a hot drink triggers extra sweating, and that as the sweat evaporates it can leave you cooler overall than ice water would.
The claim is landing at a moment of genuine urgency. Since late May 2026, Europe has been battered by successive severe heatwaves, with temperature records broken across more than a dozen countries including France, Germany, Spain, Italy and the United Kingdom. France alone recorded over 2,000 excess deaths in June, and the World Meteorological Organization has warned that such extremes are becoming more frequent, intense and prolonged.
Where the claim comes from
The counterintuitive idea that a hot drink can cool you down is not an internet invention. It traces back to a 2012 study led by Dr Ollie Jay, then a researcher at the University of Ottawa’s Thermal Ergonomics Laboratory. His team had cyclists drink water at a range of temperatures while wearing skin sensors and having their heat storage precisely measured. Those who drank hot water – around 50°C – actually stored less heat in their bodies than those who drank cold water.
The belief is in fact an old one. Traditional systems of medicine have long recommended warm drinks in hot weather rather than cold ones. In traditional Chinese medicine, iced drinks are generally discouraged as taxing to the spleen and stomach and disruptive to the body’s internal balance, while warm brews such as tea are favoured for helping the body “release heat” through the skin. Ayurvedic practice similarly cautions against very cold drinks and leans on warm, spiced infusions in the heat.
The mechanism, as Jay explained to Smithsonian Magazine, comes down to sweat. Heat-sensitive receptors in the mouth and throat detect the hot drink and signal the brain to ramp up perspiration. “The amount that you increase your sweating by – if that can all evaporate – more than compensates for the added heat to the body from the fluid”, he said. In other words, the small amount of heat added by the drink is outweighed by the cooling produced when the extra sweat evaporates off the skin.
The catch the post barely mentions
Note the five words that carry the analytical weight in Jay’s account: “if that can all evaporate”. This is the crux of the matter and precisely the element that the viral post reduces to a passing mention of “dry conditions”.
The cooling effect only works if the additional sweat can actually evaporate. As Jay puts it, drinking a hot drink lowers heat storage “provided the additional sweat produced when you drink the hot drink can evaporate”. When the air is already heavy with moisture, as it is in humid enivornments, sweat cannot evaporate efficiently – it simply pools on the skin. His rule of thumb is blunt: “If the extra sweat just drips on the ground, then you’re better off drinking a cold drink”.
Strictly speaking, humidity does not make evaporation impossible – ambient air is almost never fully saturated – but in humid conditions sweat cannot evaporate fast enough to keep up with the body’s heat load without strong airflow. That is why a fan or a breeze cools someone down considerably, and why standing still in sticky and humid air does not.
Why this matters for Singapore
Here is where the advice, sound as it is in the right setting, becomes actively unhelpful for local readers. The post was written for a European audience sweltering in a largely dry continental heat dome – closer to the desert-like conditions where “cooling by heating” genuinely works. Singapore, with its equatorial tropical rainforest climate is close to the opposite environment.
Our relative humidity routinely sits in the 70 to 90 per cent range. In that kind of mugginess, sweat lingers on the skin rather than evaporating, which is precisely why our hot days feel so oppressive in the first place. That means the hot-drink trick largely fails here: the drink still adds heat to the body, but the extra sweat it provokes has nowhere to go. A hot beverage on a humid afternoon is more likely to leave you hotter, not cooler – and in our climate, the iced drink the post tells you to skip is the better call.
The bottom line
The underlying science is real: in hot, dry conditions where sweat can freely evaporate, a hot drink can leave you marginally cooler than ice water. The post is not fabricating a study. But it strips away the single condition that determines whether the advice applies to the person reading it, burying “if the sweat can evaporate”. For a reader in humid Singapore, following it would most likely make things worse.
Therefore, we rate the claim that a hot drink cools you down faster than ice water as mostly true, but with the caveat that it only works only under specific dry conditions that do not describe Singapore’s climate.
