Swat Summer Medical Myths

Jun 19, 2012

True or False. Urine can alleviate a jelly fish sting. A poison ivy rash is contagious.

False. As summer begins, we re-examine common beliefs such as these.

Indiana University School of Medicine pediatricians Aaron Carroll and Rachel Vreeman investigated and debunked medical myths in studies published in 2007 and 2008. Their research evolved into two books: "Don't Swallow Your Gum!" and "Don't Cross Your Eyes...They'll Get Stuck That Way!"

Vreeman was online Tuesday, June 19 to discuss summer health myths.

Should you wait an hour after you eat to jump back in the pool? Is the mayonnaise at the picnic going to make you sick? Do you really need to use the very highest SPF sunscreen?


This is Dr. Rachel Vreeman. I am a pediatrician, researcher, and co-author of two books on medical myths -- Don't Swallow Your Gum! and Don't Cross Your Eyes...They'll Get Stuck That Way. I'm happy to answer any questions you might have about whether those crazy things you heard about your body and health are true. Let's get started.

My mom was a rigorous enforcer of this rule. You can blame the Red Cross for this myth.

I grew up with a pool and my parents were very strict about this one too. I thought that if I so much as put a toe in the water too soon after I ate, I might cramp up and die. There is just no proof that this is the case. In fact, no drownings have ever been attributed to eating.

A primetime TV show perpetuated the myth of urine alleviating a jelly fish sting when they showed it on national TV. I, and I suspect many others, had never even heard of the myth until it was shown to us. I wonder what responsibility TV, especially reality shows, have in extending or killing medical myths?

Many myths are perpetuated over and over again in the media. Every Thanksgiving, we hear about how turkey makes people sleepy. At Halloween, we hear about how strangers are poisoning children's candy. But studies and investigation show these things are just not true. We really try to share the science disproving these myths because all too often I even hear "experts" sharing myths.

Hello Dr. Vreeman, I've tried everything for these bug bites I have - calamine, cortizone. etc. Like the article said, I don't want to scratch. They'll get infected. What can I use for the itch??

It depends a bit on the type of bite, so if you have questions about that, it is good to have a doctor look at them. For mosquito bites, I am a fan of the topical gels that contain an analgesic -- something that reduces pain. Another thing that sometimes helps for a little while is to apply an ice cube for 30 seconds or so. This helps by reducing the inflammation.

Hi, does the pollen found in local honey really help reduce seasonal allergies? Thanks!

Nope. This is a myth we cover in detail in Don't Cross Your Eyes. The theory is that local honey contains the same allergens that are giving you allergy problems, but in small amounts, and so it helps your body fight them off. Sadly, this just does not work. It has been studied in allergy sufferers, and it does not help any more than a placebo.

I'd like to get pedicures every week now that it's summer. Is that a good idea? I'm a little worried about toenail fungus.

My disclaimer: I love pedicures! It is possible that a pedicure could give you toenail fungus, but usually only if they do not practice good hygeine with their tools and water. Use a reputable place and try to avoid techniques that lead to more cutting of your skin. And enjoy!

Someone told me about running hot water, as hot as you can stand it (which in my case would not be scalding; I have a low pain threshold) on mosquito bites. I've found this to be surprisingly effective (and mosquitoes LOVE me).

Hot water might help you feel less itching and discomfort in the short term because of how it distracts your nerves, but there is a potential downside -- exposure to a lot of heat or hot water can increase your skin's inflammatory response over all. This means you might have even more itching later on.

Do you get plantars warts from running around outside in bare feet? I heard this recently and it sounded suspicious to me! Plus I love to go without shoes!

Well, I'm afraid this is partly true. Plantar warts are caused by a wart virus, and for the virus to infect you, it needs to have contact with your bare skin. This happens most often in wet places that you walk with bare feet -- like showers or around pools. You're more susceptible if you have little cuts or abrasions in the skin on your feet.

It's skinned knee season! What are your thoughts about the Hydrocolloid "advanced healing" bandages? They are the heavy-duty waterproof kind. They claim to ensure quick healing without infection by creating a moist environment. Seems like a great opportunity for bacteria to me, but I'm no pro. Ok to use with an antibiotic cream like Neosporin?

I always thought that it was better to let a wound air out, but it turns out I was wrong! It's a myth. Wounds actually DO heal faster in a moist environment, and so a bandage that keeps them clean and moist really does offer a good solution. Studies have shown this over and over. While an antibiotic cream or ointment is a fine thing to use with one of these bandages, stay away from the hydrogen peroxide! It doesn't help! And it can actually slow healing.

Perhaps I wasn't clear: the hot water actually seems to kill the mosquito bite. I rarely have any itching after my bites have cooled off.

It's great that it works for you for mosquito bites.  I was just offering the warning that the body's reponse for bites and rashes is often made worse with hot water. That being said, as someone plagued by mosquitoes myself, I may try it!

Now's a good time to remind ocean swimmers about rip currents.

Rip currents are a danger for people who swim in the ocean. If you get caught in one, stay calm, conserve your energy, and try to swim out of the current in a direction that follows the shoreline.

Does chicken soup really help you get better when you have a cold?

Actually, chicken soup is one of the few things that you heard from your mother about cold cures that might not be a myth! The limited scientific evidence suggests that it might help -- it activates some of the cells of your immune system to fight infection. Plus, the warm steam can help with congestion.

Do you think there's really any way to avoid getting the flu should your little children get it? I mean, I can't not hug my 10-month old just because he's sick.

Wash your hands. Wash your hands. Wash your hands. And try to avoid direct contact with snot as much as possible. And when you can't avoid it, wash your hands.  (And, flu vaccines are a very good idea for everyone in the family!)

Does the shape of a pregnant mother's belly give any indication as to whether it is a boy or a girl?

Nope. People have tested a bunch of different ways to predict whether or not the baby is going to be a boy or a girl. We looked into lots of them in Don't Swallow Your Gum. And none -- including the shape of the belly -- accurately predict the gender. Your odds of guessing right are 50/50. It's hard to beat that!

Any truth to beer before liquor...never sicker?

There is no scientific evidence to support this. It really comes down to how much alcohol you drink -- not what form it is in. And hangover cures are a whole set of myths unto themselves...

Dr. Vreeman, I am beyond pale (Kasper-the-friendly-ghost white) - is there really a difference between SPF 45, and say SPF 100+? I've been buying products with very high SPF for a while now. Headed to the beach next week, so I'd love some advice. (And yes, I'll stay covered up as much as I can, too).

As a pale Dutch person -- and one who works at the Equator -- I understand your dilemma. The difference between SPF 45 and SPF 100 is very, very small. I very much endorse sunscreen, but what will really make a difference for your skin is putting on a LOT and putting it on often. You will usually get much better protection if you buy the (often cheaper) SPF 45 and put a ton of it on every two hours or after every dip or sweat.

I noticed when my son had chicken pox years ago that the sores that were exposed to the air (on his face, arms etc...) healed faster than the sores that were under his clothes. He didn't scratch or pick so that wasn't an issue. Just thought that was interesting.

I have not seen studies testing what works best for healing chicken pox sores. The studies are mostly for cuts and wounds, with some studies of induced blisters. One thing about chicken pox is that the face is one of the places that the rash often starts, so that may have seemed to heal more quickly.

Can supplements (I've heard garlic and some others) make you less attractive to mosquitoes? I get bitten all the time and I hate using the chemical spray repellant and the citronella type stuff just doesn't work.

I really hoped we would find something that you could eat to make yourself less attractive to mosquitoes. They love to bite me, and I swell up terribly. Unfortunately, nothing eaten or swallowed has been proved to repel mosquitoes. Garlic does not help. Bananas do not help.  The best repellant is still DEET. Citronella has been shown to have some effect, but not nearly as much as a repellant that contains DEET.

This is the latest one I've seen as a 'cure all' for sunburn. Your verdict?

I have heard of this one too, but I have not seen any studies of vinegar for helping with sunburns. My guess would be that it does not help, but I do not have any scientific proof.

If so, how in the world am I supposed to get rid of this loose skin given to me from my newest child?

Sadly, studies show over and over again that exercise cannot do much for one particular spot. As much as we would like those crunches to flatten our stomach, they cannot actually target a particular area for fat reduction the way we would like.

Hi Dr. Vreeman, my husband and I are trying to get pregnant. I hear that if you have a taut muscular stomach you won't get stretch marks. I work out so I think I'm in the clear but just in case, does cocoa butter really work for stretch marks?

I have not seen any good evidence supporting cocoa butter's effectiveness. The "studies" all seem to come from manufacturers of cocoa butter, and the "improvements" seem to be primarily at the level of the very surface of the skin. In other words, the skin looks more moisturized and plump (so stretch marks may be less noticeable), but it does not necessarily help to prevent or heal them.

Is it true that clear liquors, while they might result in headache and other hangover symptoms, tend to make drinkers less sick the next day than say, rum or a dark liquor? I was told that the more sugars and other "coloring" in alcohol, the greater the sickness factor.

This is another one for which there is not good scientific evidence. The evidence seems to say it is all about how much alcohol you take in -- not coloring or sugar, unless those things make you drink more!

When my son was small I could tell when he was getting sick by the way he smelled. Not a strong smell, just a slightly different smell. I told his doctor and he looked at me like I had a screw loose but I stand by my nose. What say you?

Even though I sometimes contradict mothers' sayings, I do not question mothers' ability to tell when something is wrong or different with their child. Always listen to the mother, says this pediatrician.

Is sunscreen advertised as waterproof truly waterproof, allowing you to avoid reapplying for longer periods.

Waterproof sunscreens are generally created so that they do not come off as quickly when you are in the water or sweating. But, they DO still come off eventually, so you should always reapply after swimming to keep your skin safe.

I'm not sure how you feel about this, but sometimes when I get itchy, I use hand sanitizer. I think it's the alcohol in it that cools it down. Works for me anyway. Also, when you put on Sunscreen, don't forget the tops of your ears if you wear baseball caps!

Benzyl alcohol, which is in hand sanitizers and some of the more effective ointments for itching, does seem to help with itching. Just don't put it over your whole body! And I agree with remembering your ears with the sunscreen. Ears and scalps...

Does the spray suncreen work as well as lotion? I find my super pale toddler is more tolerant of the spray "sun scream" than he is of the lotion. It is a constant summer battle, but the spray does make it a little easier, but I don't want to sacrifice protection.

I have not seen good data comparing the two, but the existing studies on sunscreen suggest that covering as much of the skin as you can and putting it on as often as you can are the 2 most important principles for sunscreen. If the spray makes it easier to corral your toddler so you can keep putting it on, then I would vote for using the spray.

If absolutely no attempt is made to toilet train a healthy child, how likely is it that the child will learn on his or her own just by observing what others do?

I have not seen any studies on this, but my expert opinion would be that it is very likely they will learn. I work in Kenya for half of the year (I am actually in Kenya right now), and many children here learn to copy adult toileting behaviors just by observation.

My mother would put yogurt on our sunburns when we were kids, saying it would absorb some of the burn (of course, cold yogurt felt good on hot skin!). But other than the fact that my family also eats plain yogurt with practically everything (we're Turks) and consider it very healthy to one's diet that way, does it actually provide any benefit to one's sunburned skin?

The cooling effect might feel nice and soothing on your sunburn at first, but yogurt is not ideal for a sunburn for the same reason that butter is not good for a burn. Both of these things can actually trap heat in the burn and ultimately make it worse. Plus, bacteria LOVE to eat and grow in both of them, so it can increase the chances that your burn will get infected.  Eat yogurt, don't put it on your burn.

Is there a difference?

We talk about a bunch of fun studies related to this in Don't Cross Your Eyes. The bottom line: hand sanitizer works really good. Better for lots of bacteria and viruses, but hand washing still wins out for mud/poop/other disgusting things you can see.

Trying to avoid last year's escapade where a tick managed to latch on (in my bra of all places) after a hike, any suggestions?

Sheesh. That's a bad location... The usual advice is to wear long pants, long sleeves, and keep things tucked in, but you may have been doing that. DEET-containing repellants work the best for ticks too.

Thanks for joining us today! I loved talking about these myths with all of you.

In This Chat
Rachel Vreeman
Rachel Vreeman is a pediatrician at Riley Hospital for Children and an assistant professor of pediatrics at the Indiana University School of Medicine. As co-field director for pediatric research of the Academic Model Providing Access to Healthcare (AMPATH), Vreeman specializes in improving healthcare for HIV-infected children in Kenya. She is co-author of two medical myth-busting books, "Don't Swallow Your Gum! Myths, Half-Truths, and Outright Lies about Your Body and Health" and "Don't Cross Your Eyes... They'll Get Stuck That Way! And 75 Other Health Myths Debunked." (St. Martin's Press)

(Photo courtesy of Indiana University School of Medicine)
Recent Chats
  • Next: