Health myths

Fact or fiction? We check out the hard, cold science behind some of summer’s hottest health myths

Do you really have to wait half an hour after lunch before you go swimming? Do windows protect you from the sun? Does sunscreen cause vitamin deficiency?

With the help of a few medical sleuths from across the country, we’ve cut fact from fiction when it comes to summer health myths. Which ones are busted? Which may just be plausible after all? And do any of them have the ring of truth?

Swimming after eating increases the chance of cramping.

BUSTED: This one is big-time busted, according to Carolyn Beck, a paediatrician at Toronto’s Hospital for Sick Children. She scoured the medical literature and failed to come up with even a single study suggesting there could be any merit to mom’s advice.

“It’s just one of those old wives’ tales,” she says, laughing at her own memory of being told to wait for a half-hour after eating before heading back in.

The theory is that blood flow is diverted from the muscles to the stomach to digest food, theoretically making you weaker and causing you to cramp while swimming. But Beck says that, at worst, your child would have to devour a huge meal and swim like a competitive athlete to be uncomfortable.

Windows protect your skin from the sun.

BUSTED: Yes, the sun’s harmful UVA rays can penetrate glass, but before you banish the kids to the basement, you should consider the science.

Richard Langley, a Halifax dermatologist and professor at Dalhousie University, says UVB rays are the ones most often linked to cancer. UVA rays typically cause photo-aging — wrinkles and moles later in life — but they can also lead to cancer. However, he says, you don’t need to break out the sunscreen indoors. “The amount of UV exposure you would need to cause a sunburn through a window would be a fair amount,” he says. There are no clear guidelines available since the amount of UV exposure varies by season, skin type and the nature of the glass itself.

Not all sunscreens are effective.

PLAUSIBLE: The science over sunscreen safety is as confusing as the labels themselves. Langley says all sunscreens on the market have been tested by Health Canada, but only those reviewed by the Canadian Dermatology Association and found to be at least 15 SPF, non-comedogenic, with a broad-spectrum UVA block can bear its logo.

However, a study of more than 1,000 sunscreens by the non-profit Washington-based Environmental Working Group found that only 15 percent met their criteria for safety and effectiveness, which includes “blocking both UVA and UVB radiation, remaining stable in sunlight, and containing few if any ingredients with significant known or suspected hazards.”

Stephanie Jennings, a naturopathic doctor in Port Elgin, Ont., says the higher the SPF, the more chemical ingredients you’re exposed to. But, she says, the more pressing danger is that sunscreens make us feel invincible against the sun. Jennings recommends using sunscreens that contain antioxidants, such as green tea extract, that eat up the harmful free radicals caused by the sun.

Langley recommends most people use a sunscreen with an SPF of 30, which screens about 97 percent of UVB rays, the so-called burning rays.

Sunblocks (zinc oxide, titanium oxide) may be a good choice for children who have sensitive skin or are allergic to sunscreen. However, they leave a white cast on the skin (they are not effective if they are rubbed in to the point of being invisible).
Sunscreen puts you at risk of vitamin D deficiency.

CONFIRMED: Speaking of controversial….It makes sense that if the body needs to absorb sunlight through the skin to produce vitamin D, sunscreen — which blocks the sun’s rays — could be a problem.

But before you send your kids into the sun unprotected in the name of vitamin D, Langley suggests you honestly assess your family’s sun habits. Studies show most people use only a quarter to half of the recommended amount (30 mL) of sunscreen and, of them, he says very few can truthfully say they never go outside without sunscreen.

“A few minutes a day is all that’s needed of unprotected sun exposure for most people to get vitamin D,” he says. You don’t have to let the kids run around in their birthday suits either; even five minutes of exposed arms, hands and face will do it.

Langley recommends children eat foods fortified with vitamin D, such as milk, some cereals and margarine. Supplements should only be taken on the advice of a doctor, according to Beck.

“Unfortunately, at this point, there’s no specific recommendation from the Canadian Paediatric Society for children to take vitamin D supplements,” says Beck. “There’s no good evidence for kids and what they should be taking.”
Of course, since vitamin D is produced in the skin, sunglasses won’t halt the production of vitamin D.

Swimming lessons prevent drowning.

PLAUSIBLE: You spent countless hours lugging the kids to the pool in the cold of winter to keep them safe in the heat of summer. Was all that effort worth it? Yes, but just don’t pin your faith on your kids’ swimming skills in an emergency, says John LeBlanc, a paediatrician at IWK Health Centre in Halifax.

LeBlanc says children under four years are not old enough to swim on their own, and they’re too young to react in an emergency. “No amount of lessons, PFDs (personal flotation devices), etc. can replace supervision close enough that you can act if necessary,” he reminds parents.
According to the Canadian Paediatric Society, drowning is the second leading cause of death in Canadian children under four years, after car accidents. Susie McRae, a nurse practitioner at BC Children’s Hospital in Vancouver, adds that while older children may be stronger swimmers, that can also lead them to become overconfident and take risks. “We can arm our kids with the education and the skills, but they have to be developmentally ready and have the endurance to get out of harm’s way and safely to shore,” she says.

McRae says that in addition to properly supervising children near water, parents should also make sure they know what to do in an emergency, including how to rescue a drowning child or give CPR.

The Lifesaving Society offers a program called Swim to Survive, which teaches children, in three lessons, the minimum skills they need to survive a fall into water. For more information, go to lifesaving.ca.
You should put ice on a sunburn.

BUSTED: Mom was wrong. Ice — and butter, for that matter — is not a fix-all for a burn. Ice can lead to frostbite; butter can hold in the heat and make it worse.

Depending on the severity of the burn, not much is needed beyond cool (not cold) washcloths, lots of fluids, and acetaminophen or ibuprofen for the pain, says Langley, adding you shouldn’t break blisters and you should consult a doctor if your child’s burn is severe.

A 100 percent aloe vera gel will soothe the skin, as will any mild, unscented moisturizer. Langley says after-sun lotions can provide temporary relief, but a cool compress will do the job just as well.

Of course, it’s far better not to let your children get sunburned in the first place. Slather them with sunscreen at least half an hour before they head outdoors and reapply it every two hours or after sweaty activities and swimming. Make sure they wear a wide-brimmed hat, and try to limit their direct sun exposure between the hours of 10 a.m. and 3 p.m.

Kids should not use bug repellent with DEET.

PLAUSIBLE: With the threat of West Nile virus, it’s easy to see why DEET is making a comeback in repellents. But is it safe? Yes and no, according to McRae.

The chemical called DEET is a poison, after all. It’s put in bug repellents in concentrations of 10 to 30 percent. According to researchers at Cornell University in New York, there have been cases of toxic encephalopathy — agitation, weakness, disorientation, seizures and even coma — reported in children who have used DEET. But it’s rare.

McRae says when parents follow the guidelines, DEET is safe. Children aged six months to two years should use bug repellent with 10 percent DEET and only once a day. Those aged two to 12 should use the same concentration, with applications up to three times a day. Only children over age 12 should use 30 percent DEET and, even then, sparingly. Never apply it on the face and hands, regardless of age.

Then make sure the kids hit the bath before bed. “It needs to be washed off with soap and water as soon as it’s no longer needed or relevant,” says McRae. “It’s not water soluble so it won’t just wash away on its own if they go swimming or if they sweat.”

Even better, according to Beck in Toronto, is to spray only on top of clothing and exposed skin because it’s closer to the bugs and less toxic. “You don’t want to trap it underneath clothes,” she says.

There are non-DEET options. Caroline Meyer, a naturopathic doctor in Toronto, says a blend of essential oils can be effective, in the right combination. She mixes two or more essential oils (such as catnip, citronella, lavender) in a ratio of 20 drops (in total) to 25 millilitres of carrier oil (such as olive oil or isopropyl alcohol).

However, Health Canada evaluated the safety of citronella and lavender a few years ago and found that while there was a lack of data about their safety, there was no proof of risk, either. Both oils remain on the market. Meyer says it’s important to make sure they’re well diluted when using them on kids.
Babies under six months should not use bug repellent with DEET.

CONFIRMED: “Never, never, never,” says McRae, of repellents with DEET. “They’re putting everything in their mouths. They’re at a high, high risk of ingesting it.” Not only that, Beck adds, but DEET has not been tested on babies, for obvious reasons. She says it’s far better to use netting around a baby outdoors.

Any pair of sunglasses will protect your eyes.

BUSTED: Uh-oh, it might be time to wrestle those cute little cartoon-character shades from your four-year-old! If they aren’t labelled to block out 100 per cent of UVA and UVB rays, they’re useless.

Don’t be tricked by darker lenses either, says Trevor Pilipchuk, an optometrist at Lakeland Family Eyecare in St. Paul, Alta. Although you shouldn’t be able to see your baby’s blues through the shades, darker lenses that don’t provide UV protection can do more harm than good. The pupils dilate in very dim conditions, allowing more UV rays to enter the eyes.

Pilipchuk says you should also peek through the lenses first to make sure your child can see clearly. Cheap lenses often distort your little one’s vision and put strain on his peepers. Go for better-quality wraparounds that keep peripheral UV rays out.