With the blistering heat getting many of us hot and bothered, we got NTU experts to weigh in on common methods for keeping cool on warm days. Find out which ones really work
by Derek Rodriguez / Illustrations by Vivian Lim
DOES KEEPING INDOOR PLANTS AT HOME HELP WITH THE HEAT?
There are many benefits to keeping such plants. They perk up your home and are fun to tend to. But do they help with the heat? Not necessarily, says Asst Prof Kelly Andersen from the Asian School of the Environment.
“It might be ‘cool’ to stock your home with houseplants, but they may make your home less comfortable. Plants release water into the air as they conduct photosynthesis, adding to the humidity level in your home. And high humidity can make it feel warmer than it actually is,” she says.
However, it might be a different story if they provide shade from the harsh sun outside.
“Just like trees in the forest, large plants can keep indoor temperatures from rising by blocking the sun’s rays from heating up your home,” says the ecologist.
DOES AVOIDING “HEATY” FOOD OR HAVING “COOLING” DRINKS WORK?
Would you raise your eyebrows at your mum and dad if they tell you not to have curry on hot days? They might not be entirely off the mark, says Dr Tjioe Yan Yin, a senior physician at the NTU Chinese Medicine Clinic.
“In Traditional Chinese Medicine (TCM), the heat on hot days can increase the body’s yang qi (flow of energy) and result in symptoms such as increased body temperature, thirstiness and sore throats. If we consume food that is hot or ‘heaty’, such as fried or spicy food, this can add burden to the body’s defence mechanism in fighting the heat, which increases the likelihood of these symptoms.”
What about “cooling” drinks from TCM shops that are touted to be remedies for “heatiness”?
“Take them in moderation,” says Dr Tjioe. “They help keep the body cool by balancing out the ‘heat’ within the body, but can be taxing on your digestive system.”
WILL DIPPING YOUR FEET IN COLD WATER COOL YOU DOWN?
Putting your feet in a basin of water or washing them could help you feel less warm. But according to Dr Fabian Lim from Lee Kong Chian School of Medicine, this might be an illusion.
“Your hands and feet have a large volume of sensory nerves for temperature, making them highly sensitive to surface or ambient temperature. Dipping them in cold water ‘tricks’ your brain into thinking that your body is cool and promotes a sense of thermal comfort. However, this method has limited effects on the actual amount of heat removed from the body.”
“You can cool your body more effectively by taking a cold shower or wiping yourself down with a cold towel and bringing a fan near you,” he suggests.
CAN YOU PLACE A PAIL OF ICE WATER IN FRONT OF A FAN TO COOL A ROOM?
Behind air conditioning, the electric fan is man’s best friend on hot days in Singapore. In the sweltering heat, some people have resorted to placing pails of ice water in front of fans to cool their rooms. What’s the science behind this?
This is based on the principle of evaporative cooling and works to an extent, say Assoc Prof Wong Teck Neng and Asst Prof Ho Jin Yao from the School of Mechanical & Aerospace Engineering. It relies on the same concept as the mist-blowing fans you see at some outdoor eateries.
Water absorbs heat from the surrounding air as it evaporates, which reduces the air temperature, say the thermodynamics experts. “But in a humid climate like Singapore’s, its effectiveness is limited,” notes Asst Prof Ho.
This story was published in the Jul-Aug 2023 issue of HEY!. To read it and other stories from this issue in print, click here.
