INTUITIVELY, reaching for a cold drink seems like the logical choice to stave off the heat on a hot day. It makes sense, right? Cold drink plus heatwave equals less suffering.
However, a paradoxical practice suggests that having a hot beverage instead can actually help to cool you down faster.
Is this true?
Verdict:
PARTIALLY TRUE
The science behind drinking something hot to cool down hinges on the body's natural mechanisms for temperature regulation.
When you ingest a hot drink, the body’s response is to sweat – a biological mechanism for dissipating excess heat. And as sweat evaporates from the skin, it takes with it some body heat, thereby resulting in a cooling effect.
According to Ollie Jay, a researcher from the University of Ottawa’s School of Human Kinetics we "have a disproportionate increase in the amount that (we) sweat" when we ingest hot drinks, hence why they can be effective in bringing our core temperature down.
However, there is a caveat: for the sweat-induced cooling system to work effectively, the sweat must be able to evaporate.
In high humidity environments, such as tropical Malaysia, where the air is already saturated with moisture, sweat evaporation is significantly less efficient. This means that excess sweat might end up staying on your skin and make you feel even hotter.
"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," says Jay.
Aside from environmental considerations, individual physiology also plays a role in how effective this unorthodox cooling method might be.
Factors like metabolic rate, acclimatisation to the climate you are in, and overall health and hydration can influence how well one’s body responds to hot drinks in terms of temperature regulation.
Even the clothing you are wearing matters, as some, such as activewear, allow sweat to escape more easily, while other fabrics tend to trap sweat.
All things considered, this method of cooling off sadly only works under very specific circumstances – it needs to be hot but dry, and you can’t be wearing clothing that prevents your sweat from evaporating.
In Malaysia, the best way of beating the heat is still via hitting the fridge! Still, now you have an interesting fun fact to bring up if you want to get incredulous stares from your friends on a hot day.
References:
1. https://www.smithsonianmag.
2. https://www.livescience.com/
3. https://skepticalinquirer.org/
