It is a scorching hot summer’s day, and the sheer intensity of the heat makes you feel hot and thirsty like nothing! Understandably, you want to grab a glass of cool, refreshing beverage the first thing to sate your thirst and to feel comfortable.
But here’s the question. What Should you reach for at such a moment: an ice-cold beverage (a glass of chilled juice or soft drink, etc.) or a sizzling hot cup of tea? For far too many people, this is a no-brainer—they will go for the chilled drink. But here’s what science tells us: on a summer’s day, a hot drink will make you feel way more comfortable than if you drank some chilled beverage.
How come, you say?
Well, here’s how it works.
Neuroscientist Professor Peter McNaughton at the University of Cambridge explains that drinking hot beverages helps raise our core body temperature, which, in its turn, makes us sweat at an increased rate.
The heat of the beverage acts on the nerves in our upper digestive tract and our mouths, stimulating the brain to produce higher amounts of sweat. And as this excess sweat gets released from our skin pores and evaporates, the process, on the whole, helps cool us down.
A specialist in human thermoregulation, Dr. Christopher Gordon from the University of Sydney, provides a more thorough explanation on why people feel cooler once they drink a hot beverage when the heat is already up.
According to Dr. Gordon, although the sweat glands are distributed all across our skins’ surface, this distribution is considerably higher in areas such as the lower leg region, the hands, and the head. This is why once we sweat, we perceive a noticeable change in skin temperature in those areas (especially in our face), and we feel cooler.
Dr. McNaughton adds that regular sweating is essential for the human body to function properly in a hot environment. Since, otherwise, our body’s central or core temperature will rise, and even a rise of a couple of degrees can prove fatal and can lead to serious brain damage and death even.
A Nice Cup of Hot Tea Is All You Want
Therefore, no matter how enticing it appears, the next time you feel hot all over, and your throat is scorched, reach out for a nice, good cup of hot tea and not for some chilled beverage. Of course, a cup of hot coffee will work as well; however, it’s better to settle for tea than coffee since the latter comes with other effects due to the high levels of caffeine in it.
McNaughton further remarks that hot meals—like chili hot—work just as well when it comes to keeping us cool in a hot environment. Since capsaicin, the active ingredient found in chili peppers triggers those same heat-detecting nerves in the mouth and the digestive tract that make the brain produce more sweat.
A sizzling spicy dish such as tandoori chicken on a hot day?—the very thought is enough to make most of us sweat! And yet, as Dr. Gordon explains, there is a reason why people living in warmer climates, such as those in tropical regions of South America, Asia, and India, often prefer spicy dishes over so-called cool and refreshing comestibles such as frozen treats, melons and the like.
Dr. Gordon explains that spicy foods, due to different active ingredients found in those spices, help trigger our central nervous system. The heat in the mouth we feel leads to an increase in the skin temperature, resulting in sweating and a dilating of our blood vessels (the process known as ‘vasodilation’ in medical jargon). And this sweating and vasodilation make the heat move away from the body to the surface of the skin and subsequently, in the surrounding air, thus cooling us down again.
On the other hand, opting for a refreshing ice-cold beverage on a hot day will make us feel hotter and not the other way round. This is because the cold of the drink tightens the blood vessels instead of dilating them. So, even if you feel cool and refreshed after consuming such drinks, the effect will wear away pretty soon, and you’ll start to feel even hotter than before. According to Dr. McNaughton, the cooling effect we get from the cold beverages gets diluted pretty quickly, chiefly since the beverage volume is quite small about our body. And of course, as McNaughton puts it, you “cannot and should not drink too much since that will simply overload your kidneys” and will cause a range of other problems.
With the temperature rising pretty fast this week in many parts of Western Europe, we requested our social media followers to share their favorite methods for staying cool during the summer months. Two suggestions that headed the list were:
- Dipping one’s feet in an ice bath (often sitting in front of a fan)
- Wrapping wet towels around heads and wrists
We put those suggestions to Dr. McNaughton, and he was in favor of them both. He also explained why these methods work pretty well. With wet towels, the professor explained, the process is pretty much the same as sweating. As the water in the towel evaporates, we feel cooler. And the logic behind wrapping it around one’s wrist or head simply follows from the fact that these parts of our body come with a higher concentration of sweat glands compared to others.
The ice-bath directly cools down our feet, and thanks to our highly efficient bloodstream, this cooling effect (from the cold blood) is transmitted quickly to the center and helps us keep cool. Also, the fan helps evaporate the sweat even more quickly, thus helping us cool down rapidly and stay that way.