6 surprising, scientifically-backed ways to cool down quickly during a heat wave
Some of this advice may seem counterintuitive, but it may help you beat the heat.
Heat waves are hitting across the globe, and getting worse every year.
Phoenix is known for its scorching hot summers, with temperatures sitting at or above 100 degrees for much of the season. But even those seasoned by the Sonoran sun are struggling with nearly three weeks straight of high temps over 110 degrees, with overnight lows not dipping below 90 degrees for days on end.
(Having lived in the Valley of the Sun myself, I can attest that, yes, there is a significant difference between 100 and 110 degrees. At 100, you can still legitimately pull the "But it's a dry heat!" card. Over 110 is just miserable, not to mention dangerous.)
The Southwest isn't the only place experiencing record heat. The Lower Mississippi Valley and Florida are feeling it, and globally we're seeing parts of Europe and Asia breaking their own heat records as well.
With the globe predictably heating up due to climate change, there doesn't appear to be much end in sight for extra-oppressive heat waves. So aside from taking the necessary steps to curb climate change, we have to focus on how to cool ourselves down. There's a lot of conflicting advice out there, but here are some scientifically-backed ways to cool your body down quickly, especially if you don't have air conditioning or access to a pool or lake or river nearby.
1. Focus on cooling your hands and feet.
Everyone seems to have a different body part to focus on first for the quickest cool-down—your face, your neck, your wrists, etc.—but according to Professor Mike Tipton from the Extreme Environments Laboratory at the University of Portsmouth, the hands are where it's at.
"Your hands have a high surface area to mass area—they have lots of blood flowing in them when you’re hot. If your core temperature is hot, your body will send blood to the extremities in order to lose heat,” Tipton told Science Focus.
“Immersing your hands in cold water won’t feel as nice, but it’ll cool you much faster than even an ice bath! It’s so important to make a distinction between things that make you feel cooler and things that actually make you cooler.”
Cooling your feet works for the same reasons. We have lots of blood flow to our feet, so immersing them in cool water (not ice water, as that causes the blood vessels to constrict and reduce blood flow) can help cool you down quickly.
2. Try drinking hot liquids.
Yes, drinking cold drinks feels amazing when you're hot, but some experts say hot drinks can actually do more to help your body's natural cooling system work more efficiently. Ollie Jay, a researcher at the University of Ottawa’s School of Human Kinetics, explains why.
“What we found is that when you ingest a hot drink, you actually have a disproportionate increase in the amount that you sweat,” Jay told The Smithsonian. “Yes, the hot drink is hotter than your body temperature, so you are adding heat to the body, but 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.”
The one caveat is that the increased sweat has to have someplace to evaporate, so take humidity levels into consideration.
“On a very hot and humid day, if you’re wearing a lot of clothing, or if you’re having so much sweat that it starts to drip on the ground and doesn’t evaporate from the skin’s surface, then drinking a hot drink is a bad thing,” Jay added. “The hot drink still does add a little heat to the body, so if the sweat’s not going to assist in evaporation, go for a cold drink.”
3. Try some spicy foods, too.
Have you ever noticed that tropical places often have the spiciest foods? There are several theories for why that is, but one of them may be that spicy foods can actually help you stay cool.
Similarly to drinking hot beverages, eating spicy food makes you sweat, and sweat is the body's main cooling system. (Again, though, the effectiveness of this approach depends on your sweat being able to evaporate, so you may not benefit from your mouth burning if you're in a very hot and humid climate.)
4. Ditch the fan if it's extremely hot AND extremely dry or humid.
Fans can provide a nice breeze to help you cool down, but many public health agencies have recommended against using fans above 95 degrees F (35 degrees C).
However, Ollie Jay and 12 colleagues published a study in 2021 that found humidity levels make a difference in whether fans are actually effective for cooling in extremely high temperatures. Essentially, if temps are extreme and conditions are very dry or very humid, fans can make things worse. But as Science Alert points out, those conditions are not the norm in most places. When humidity is moderate, the temperature at which fans are effective can be higher than 95 degrees.
"[T]here are many locations on Earth where fan use could be safely recommended as an alternative to air conditioning all of the time despite air temperature exceeding the currently recommended threshold of 35 °C," the authors wrote.
(However, it is important to note that fans increase the risk of dehydration, so always make sure you're drinking plenty of fluids. And for older adults, fan use is not as effective as it is for younger people and can actually result in raising their body temperatures. So it's important that elderly folks and their caregivers follow heat guidance specifically for older adults.)
5. Just say no to the cold beer—or any alcoholic or caffeinated beverage
Cracking open a cold one may sound incredibly refreshing when you're sweltering, but alcohol and heat actually make poor bedfellows. That's because alcohol actually dehydrates you. Same goes for caffeine. And the fact that they are liquids is especially deceptive because they give you a false sense of hydration.
“If you’re drinking a lot of beer or alcoholic seltzer, it can feel like you’re taking in a lot of liquid and staying hydrated,” registered dietitian Julia Zumpano, RD, LD, tells the Cleveland Clinic. “But the alcohol offsets that because of the dehydrating factor.”
(If you're interested in the biological reason for alcohol being dehydrating, it reduces the release of vasopressin, an antidiuretic hormone (ADH) that works with your kidneys to keep your body fluids balanced. Alcohol is also a diuretic, which means it increases the fluid being pulled out of your body as urine.
Hydration is key to making it through a heat wave, so drink aplenty, but make it water. (And start hydrating early in the day. Keeping water near you at all times and continually drinking throughout the day will go a long way toward preventing heat illness.)
6. Try dabbing on some peppermint oil
I know, I know. Essential oils are quack cures and whatnot. But in this case, even though it doesn't drop your core temperature, there really is a scientific basis for topical peppermint oil making you temporarily feel cooler.
Menthol, the primary ingredient in peppermint oil, has been shown to induce a cooling sensation. If you've ever sucked on a menthol cough drop, you know the feeling. Peppermint oil creates a similar sensation on the skin, which can provide some psychological relief from the heat, even if it's not actually reducing your body temperature.
In one study, a menthol gel was found to have a longer cooling effect than either ice or a placebo gel on healthy males. But anecdotally, a few dabs of peppermint oil on my wrists, neck and inside my elbows provides some instant cooling relief on very hot days. When it's brutally hot outside, any bit of relief helps.
There are plenty more tips for beating the heat, from wearing light-colored clothing to avoiding strenuous activity, but the big takeaway from this list is helping our body's built-in cooling system work as well as it possibly can during extreme heat.
For more information about the dangers of heat waves and how to prevent heat illness, check out the American Red Cross extreme heat safety tips here.