Dressing for the summer to stay and look cool involves more than picking out a white T-shirt and shorts. Choosing the right fabric, according to experts in fashion and dermatology, is about a breezy fit, and remembering to hydrate.
Henry Navarro, associate professor at Toronto Metropolitan University's school of fashion, stresses the need to use multiple forms of protection against the sun and heat, including to choose long, loose clothing, wear a hat and carry an umbrella for shade.
"There's no silver bullet to protect against the heat and sun," he said in an interview Wednesday, but he adds that North Americans can learn about staying cool from dress traditions in warm and humid countries.
"We can learn (from) historically proven ways to cope with different environments."
Navarro traces the trend of stripping down in the summer to the 1950s in North America and Europe, when there was a "sudden appearance of leisure time for the middle class."
Middle class families started having disposable income, and along with that came summer activities such as barbecuing and lounging by the pool with uncovered legs and arms. "And it started this kind of movement of shedding clothes during the summer."
But hotter regions of the world dress traditionally — covering up to keep out the sun's rays and stay cool, he said.
Navarro, who grew up in the Caribbean, said people wear loose, linen clothing in light colours to ensure they stay comfortable in humid heat, and also protect themselves from mosquitoes. On Wednesday in Toronto, with the humidex hitting 30, he was wearing a light blue linen shirt, a white T-shirt, and trousers.
Those who live in hot, dry environments, such as Bedouins — nomadic people from the Arabian Peninsula, Middle East and North Africa — dress differently than those in tropical, humid areas, Navarro said. They cover their heads in turbans and wear long clothing, while those in tropical, humid areas prefer linens in light colours, he added.
"In Spain, wool clothing is worn year-round," he said.
Dr. Monica Li, an assistant professor at the University of British Columbia's department of dermatology and skin science, said dressing for summer isn't about wearing less; rather, she said, people should choose clothing that is loose-fitting and can offer protection from harmful ultraviolet rays.
"Loose, long-sleeve shirts; loose, long pants; or loose skirts are actually recommended over being bare-skinned — or over a bikini — because the more you cover, the more protection you're going to get," she said in an interview.
Loose fits are recommended over tight clothing that stretches, she said. The sun's ultraviolet rays pass more easily to the skin when woven fabric stretches, reducing the level of protection, she added.
However, densely woven fabrics, such as denim, canvas, wool, shiny polyesters, silk or synthetic fibres, offer more protection against ultraviolet rays than sheer or thin material, Li said.
"If you wear a denim jacket, it's thicker, it's more uncomfortable, especially in a heat wave … but it's also definitely much better at protecting the skin," she said. "In a long-sleeve denim shirt, the SPF (sun protection factor) could be as high as 1700, which is better than any sunscreen product in the market, which is usually between SPF of 30 to 50."
Bright colours are more likely to keep ultraviolet rays from reaching the skin, as opposed to pastel shades or white, she added.
A 1980 study from Tel Aviv University about Bedouin who wear black robes in the desert showed that the colour of clothing had little to do with heat, but their design did make a difference.
The robes functioned like a chimney. Bellows of cool air flowed into the air spaces beneath the black robe, rising and passing through the loosely woven fabric as it was warmed, pulling in cooler air from the bottom, said the study published in the scientific journal Nature.
"The amount of heat gained by a Bedouin exposed to the hot desert is the same whether he wears a black or a white robe," it said. "The additional heat absorbed by the black robe was lost before it reached the skin."
Li usually wears a "sleeve guard" when driving, which goes all the way up her arm and keeps the sun away. She also wears a reflective visor when she's outside for long periods. On a recent visit to Thailand, she said she carried an umbrella and wore a dark-coloured windbreaker to reflect ultraviolet rays.
But Li adds that managing the body's temperature is not just about protecting skin but also regulating temperature, which can be done by making sure people stay hydrated. "Sun protection is ultimately about doing as much possible, within reasonable measures, to be safe in the sun," she said.
As the climate warms, Navarro said it is important to incorporate lessons from Indigenous cultures and those from Southeast Asia, Africa, Arabia, Caribbean, and Latin America.
"Ancient cultures have contributed to global fashion and global dress cultures," he said. "They have historically proven ways to cope with different environments, and we have a lot to learn from them."
