Editor’s Note: I don’t know about you, but every day I hear all sorts of people making authoritative, health-related statements, such as which foods cause certain disorders—and these people often seem to have no idea where their “facts” actually come from! Can we trust them? Well, a recent article from another publication in the Bottom Line family, Bottom Line Personal, debunks six health myths and reveals the truth about each one. Check out the article below…and to sign up for your own subscription to Bottom Line Personal, visit BottomLinePublications.com—Carole

“Don’t cross your eyes—they’ll get stuck that way.” That’s what my mother used to tell me. Of course, though my mother was right about many things, she was wrong about that.

Many of the things that we hear about our bodies just aren’t true. The result is that we may be worrying about stuff that that we don’t need to worry about or doing things that we think will help our health but won’t.

Here, six common health myths and the truth behind them…

MYTH: Airplane air makes you sick.

Reality: There’s nothing inherently more risky about airplane air. Multiple studies do show that if you’re sitting within two rows of a sick passenger, you’re likelier to catch what he/she has. But the danger is no greater than if you were to encounter that person on a train or bus, in an office or at the mall.

In fact, research shows that airplanes are cleaner than land-bound sites for three reasons…

    • The air circulated is drawn from outside, where the high altitude means few bacteria or viruses.
    • Cabin air is exchanged about 20 times an hour, more frequently than the air in most office buildings.
    • Bacteria and viruses like moist air, and airplanes typically are quite dry. (The lack of moisture may irritate mucous membranes, and some researchers speculate that this could increase vulnerability to infection, but there’s no backup for this yet.)

One real risk of air travel is that of developing deep vein thrombosis (DVT), or a blood clot in your leg, from sitting still for long periods. Avoid DVT by stretching and walking around once an hour or so.

MYTH: Cheese makes you constipated.

Reality: This bad rap probably started with the apparent connection between infant dairy intake and firmer stools, but it’s not true. According to a study by the National Center for Health Statistics, which looked at data from more than 15,000 people ages 12 to 74, the 13% reporting constipation actually ate less cheese, not more. They also took in less high-fiber food, such as legumes, fruits and vegetables.

MYTH: If you’re ill, dairy products increase congestion.

Reality: Once again, cheese—and milk and other dairy products—have been unfairly accused. Numerous studies have not found any link between milk products and phlegm production or an increase in coughing, congestion or a runny nose. In one study, people with colds were given milk but produced no more mucus than the control group.

Some people, though, are extra sensitive to how milk feels in the mouth. Milk hits the mouth in something called droplet flocculation, spreading out as tiny droplets over saliva and creating a mucus-like sensation. But there isn’t truly any more phlegm—it just may feel that way to some people.

MYTH: Tilting your head back stops a nosebleed.

Reality: Think about it. How could this possibly work? It can’t help the blood to clot or put pressure on the source of the flow. What it does do is send blood down your throat, which could cause choking or vomiting.

Instead, keep your head above your heart by standing or sitting upright…lean your body forward…and squeeze just below the bony bridge of your nose for five to 15 minutes until the bleeding has stopped. If the bleeding doesn’t stop after 20 minutes or is the result of an injury that could involve a broken nose, seek medical help right away. The same is true, too, if you have frequent incidents.

MYTH: Eating lots of protein after a workout builds muscles.

Reality: There are studies showing that some protein eaten after exercise helps build muscles. But loading up is a bad idea, because taking in excess protein can dehydrate the body, make the kidneys work harder and cause gas, indigestion and heartburn. Worse, there’s some evidence that eating a high-protein diet is connected with a greater risk for heart disease. So a little protein goes a long way.

MYTH: Stress causes high blood pressure.

Reality: Increased blood pressure is one aspect of the fight-or-flight response to stress, but there is no apparent connection between chronic stress and high blood pressure. A study that followed 36,530 people for 11 years detected no connection between anxiety and the development of high blood pressure. In fact, people who tended to be anxious actually had lower blood pressure, which could not be explained by other known factors such as medication, age and gender.

It may be that people who are under stress don’t take as good care of themselves—eating or drinking too much, using recreational drugs or not sleeping enough—and increase their risk that way. If this describes you, you know what to do.