8 Common Health Myths, Debunked

Guest author Dr. Leana Wen debunks 8 common health myths. (Hint: It turns out, you can go outside with wet hair without catching a cold!)

Leana Wen, MD
4-minute read
Episode #115

8 Common Health Myths, Debunked


I bet you've heard this from your mother time and again: You'll catch a cold if you go outside with wet hair. You'll go blind if you keep reading in low light. You'll kill off brain cells if you drink too much alcohol

Well, I'm here to tell you that these, and many other "facts" that you may have heard, are actually false. But in spite of the medical community's best efforts, these myths continue to haunt many of us.

So today, I'm going to share with you the truth (and the fiction) behind 8 pervasive health myths:


Myth #1: You'll catch a cold from being too cold.

Growing up, how many of us have heard this from well-meaning parents and grandparents? It’s easy to see how this myth came to be. People do get more colds in the winter. Going outside in the cold without proper protection or with wet hair isn’t particularly pleasant, and if you do it enough, it might lead to a weaker immune system. However, we also know that colds are viral infections that are transmitted through viruses. You catch a cold from someone else who has a cold, not from being too cold yourself. So, to avoid catching colds, be diligent about washing your hands and sharing eating utensils (though bundling up in cold weather will make you more comfortable when playing in the snow).

Myth #2: You'll go blind if you read in low light.

If this is the case, then our ancestors will surely all have suffered from blindness! It’s not true that reading in low light leads to blindness. That said, why strain your eyes unnecessarily? If you have the choice, read in an environment with lighting that is pleasant to you.

Myth #3: In order to tan, you must burn first.

This is definitely NOT true. Sunburns are potentially dangerous, and can lead to sunstroke and dehydration, not to mention skin cancer. Tanning itself carries similar risks. How much you tan depends on your skin type (there are some people who burn and never tan, for example), but you should definitely not plan to get sunburned in order to tan. That will only lead to skin damage.

Myth #4: Muscle turns to fat if you don’t use it.

Anatomically, this just isn’t the case. Muscle and fat are two different types of tissues, and one doesn’t turn into the other. However, there may be some truth behind the myth in that if you don’t exercise, you lose your muscle mass. If you consume the same number of calories as when you were exercising, you will probably gain weight. So make sure to exercise regularly! I recommend checking out Get-Fit Guy's podcast for more tips on how to stay in shape (without spending a ton of time in the gym).

Myth #5: Alcohol kills brain cells.

In junior high, I watched my teacher drop a rat brain into alcohol, and the alcohol seemed to eat away at the brain. So alcohol kills brain cells, right? Well, not exactly. The alcohol that you drink enters your bloodstream, and doesn’t actually attack your brain directly. Of course, there are other ways for alcohol to injure your brain. For example, binge drinking can lead to decrease in breathing and injury to your brain, and drinking while driving has many other dangerous consequences. But drinking alcohol per se, does not damage brain cells. However, as with everything else, drink responsibly and in moderation.

Myth #6: People are fat because they don’t exercise.

While exercise is necessary to maintain good health, the primary contributor to being overweight is poor diet. An overweight person will have difficulty losing weight by exercise alone; a good diet with decreased calories is also necessary. Genes also play a role. That doesn't mean you shouldn't exercise if you want to lose weight -- but make sure you also change your diet, otherwise you're only addressing one part of the problem. Nutrition Diva has a ton of amazing tips and tricks for eating well and feeling fabulous.

Myth #7: Birth control and HPV vaccine leads to more unsafe sex.

A myth like this is a testament to people using anything as “research” to support their views. It’s hard to imagine that anyone will choose to have more sex because they have better information and a few shots in their arm. A better way to think about this is that people are going to be sexually active anyway, so why not empower them with information to make good choices (i.e. birth control and sex education)? The HPV vaccine can guard against cervical cancer; why not protect our young? There's no evidence that birth control or HPV vaccines led to an increase in promiscuity. That is absolutely a myth.

Myth #8: Women need annual pap smears starting from age 18.

This used to be the case, but the guidelines have been revised such that it’s recommended for women to get pap smears every three years, starting from three years after they begin sexual intercourse. This doesn’t mean that you should only see your doctor every three years; an annual well woman’s visit is beneficial for a number of reasons, including checking up on your health in general and addressing other aspects of your sexual health.

Many of these myths are partially based on the truth; that’s why it’s so hard to sort them out! Yet, they have been disproven time and time again, with a variety of scientific studies. So when you hear someone perpetuate any of these myths, point them to the truth.

Dr. Leana Wen is an emergency physician and author of "When Doctors Don't Listen: How to Avoid Misdiagnosis and Unnecessary Tests." She was a Rhodes Scholar and has trained at Washington University, the University of Oxford, Harvard Medical School, and Brigham & Women's and Massachusetts General Hospitals.

You can find out more about Dr. Wen and check out her book at WhenDoctorsDontListen.com. Follow @DrLeanaWen and visit www.drleanawen.com.



Please note that all content here is strictly for informational purposes only. This content does not substitute any medical advice, and does not replace any medical judgment or reasoning by your own personal health provider. Please always seek a licensed physician in your area regarding all health related questions and issues.