Clever ways to keep your cool

Ditch icy drinks

We naturally reach for a glass of cold water when in a hot climate. While that delivers an instant cooling sensation in your mouth, your body absorbs fluid more quickly if it’s the same temperature as you, says Marie Fitzgerald, a Lloyds Pharmacy pharmacist. ‘It takes energy to warm a cold drink to your body’s temperature – and any energy expenditure makes you hotter.’ This is backed up by a study at the University Medicine Berlin, which found that drinking two cups of ice-cold water led to a 30 per cent increase in subjects’ metabolic rate, and a surge in metabolism equals a surge in body heat.

Eat a curry

Ever wondered why people in the world’s warmest countries eat such spicy food? Mike Tipton, professor of human physiology at the University of Portsmouth, explains: ‘Sweating is the body’s primary mechanism for losing heat, and a hot curry is a great way to bring on a sweat. It also opens up blood vessels in the skin, allowing more heat to escape from your body.’

Slip into sheepskin boots

Yes, really! Ugg boots were first worn by Australian surfers to regulate the temperature of their feet. Charlotte Cole, manager of Cornwall-based Celtic Sheepskin, explains why: ‘Wool is full of air pockets that allow air to circulate and your feet to breathe. Think of Ugg-style boots as akin to a flask, keeping their contents cool or warm in reaction to the temperature of the feet. We recommend that the boots are worn without socks so that the wool’s natural thermo-regulation properties aren’t hampered.’ Boots in summer are a hard look to pull off, but shearling flip flops, available for £45 from Celtic Sheepskin (www.celtic-sheepskin.co.uk or 01637 871605), work well, too. They’re even machine-washable.

Have a paddle

Dipping your feet in cold water is one of the best ways to achieve instant cool, says Professor Tipton. ‘Your feet and fingertips contain special vessels designed to allow a lot of blood to reach the surface of the skin – and with it a lot of heat. You can lose a degree and a half of heat from body temperature in just 20 minutes this way.’

Have a warm shower

Strange but true, having a tepid shower will actually lower your body temperature far more effectively than a cold one. ‘To cool down, the body delivers heat via the blood to the surface of the skin, where it then evaporates. A very cold shower can shut down that blood supply as the body acts in self-defence to preserve heat,’ explains Professor Tipton. In a tepid shower, he says, ‘blood will keep delivering your body heat to the skin, while the water conducts it away.’

Wear black clothes

In fact, wear whatever colour you fancy because, contrary to popular opinion, dark fabric doesn’t make you hotter. Intrigued by Bedouin tribes wearing black robes in hot deserts, scientists at Tel Aviv and Harvard Universities conducted a study and discovered that the amount of heat felt by a person standing in the desert is the same whether they wear a black or a white robe. The heat absorbed by the black fabric is lost before it reaches the skin. Bedouin robes, the scientists noted, are worn loose. Inside, the cooling happens by convection, either through a bellows action, as the robes flow in the wind, or by a chimney effect, as air rises between robe and skin.