Survive the Summer Heat

Nov 9, 2010
Toby Welch

Hot, Sunny Days Can be Tough - Superflewis

People come alive when summer arrives. We shed our parkas and fuzzy toques and bring out the flip-flops and tank tops. But the heat can be challenging.

The humidex is a good indicator of just how hot our summer days actually are. According to Environment Canada, “The humidex is a Canadian innovation, first used in 1965. It was devised by Canadian meteorologists to describe how hot, humid weather feels to the average person.

The humidex combines the temperature and humidity into one number to reflect the perceived temperature. Because it takes into account the two most important factors that affect summer comfort, it can be a better measure of how stifling the air feels than either temperature or humidity alone. The humidex is widely used in Canada.”

Environment Canada continues, “An extremely high humidex reading can be defined as one that is over 40. In such conditions, all unnecessary activity should be curtailed. If the reading is in the mid to high 30s, then certain types of outdoor exercise should be toned down or modified. Despite its limitations, the humidex remains a useful, and hence popular, means of determining how hot it actually feels outside.”

Environment Canada issues an advisory when the temperature exceeds 30º Celsius and the humidex climbs over 40º Celsius.

What is the UV Index?

The UV Index indicates the strength of the sun’s rays on a scale of one to ten. The higher the index, the more cautious you need to be.

UV Index categories:

8-10 Very High
6-7 High
3-5 Moderate
0-2 Low

Not just skin is affected by the sun's rays; eyes can suffer burns from the sun. According to Hans R. Larsen, MSc ChE, publisher of International Health News, "Do wear sunglasses that filter out 100% of the ultraviolet light to protect yourself against the development of cataracts."

Necessity of Water

According to Lee Finell, Nutrition Education Spokesperson for Alberta Milk, Registered Dietitian and Nutrition Educator, there are new hydration guidelines for how much fluid we need to intake. “The new hydration guidelines prove that it is a myth that anyone needs to drink eight glasses of water a day. In fact, the new guidelines are based on total fluid intake from all beverages - which includes milk, juice, water, soup and coffee and tea. The reason is that all beverages contain water—i.e. milk is 87% water. Therefore recommended intakes of fluid are:

Children aged 1-3 – four cups of fluid per day
Children aged 4-8 – five cups
Children aged 9-13 – seven to eight cups
Teenagers - eight-11 cups
Adults – nine-13 cups

It’s important to drink this much and more if you are active or it is very hot.”

Finell continues, “It’s best to drink nutritious fluids such as milk and juice or water rather than sweetened beverages. It’s particularly important to ensure that children drink enough - they tend to play hard and not remember to drink.”

Dehydration is one of the most common heat dangers. It occurs when we are not getting enough liquids. Water is necessary for our bodies to prevent over-heating. With intense summer heat, dehydration can occur rapidly so drink up! The first sign of dehydration is being thirsty. Then you will notice your urine is dark and concentrated, a sure sign of dehydration. Urine should be pale yellow. As dehydration worsens, people can experience cramps, nausea, grayish skin tone, dry skin, light-headedness and fatigue.

As for what to eat to beat the heat, consume smaller meals but more frequently. Avoid heavy foods. Don’t hover over a hot stove cooking. Consider using the outdoor barbecue instead of the oven.

Lee Finell suggests eating, “Foods with a high fluid content such as watermelon, oranges or Popsicles made with fruit juice or fruit juice and yogurt.” Eat cold soups, frozen grapes, sandwiches and fruit right from the fridge on those hot summer days.

Children and the Heat

Children are especially vulnerable to the summer heat. Their bodies aren’t fully developed and aren’t able to cool themselves as efficiently as adults.

Parents, your kids won’t remember to drink water so make sure they are taking it in. Discourage sodas and go for the sports drinks if water won’t do.

Never leave your child alone in a car in the scorching sun. General Motors conducted a study that showed that at least 25 children a year die in North America when they are left in a hot vehicle. Don’t let your child be one of these statistics.

Seniors and the Heat

Seniors have more trouble than the rest of the population handling the heat for many reasons – medications that magnify the effects of heat, chronic disorders, normal aging that affects their body’s ability to cool off and sweat glands that no longer work as efficiently, among others. Seniors need to do everything possible to stay cool. Check on elderly neighbours during heat waves.

If you are a senior who needs to travel during times of high heat, call a taxi or another source for a ride. Do not wait in the sweltering heat for the bus.

Best Clothes to Wear in the Heat?

Light-coloured, loose-fitting starch-free clothes are the best to wear during times of high heat. Light-coloured clothes will reflect the sun’s rays whereas dark clothes absorb the heat. Ensure the weave on the clothing is tight as a loose weave will allow UV rays to penetrate. Wear a light-coloured wide-brimmed hat that allows for airflow and covers your neck and ears and well as your head.

For tips on how to survive the scorching hot days, check out How to Cool Off When the Heat is Rising

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