Popular Medical Myths Exposed

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Medical myths are false beliefs about health that we pass on to others, usually done with the best of intentions. Indeed, even many of my fellow doctors fall prey to them. Here, a few of the more common ones.

1. Going out in the cold causes a cold.
Many studies have been done on this topic, and the result it clear – going out in the cold does not cause you to get a cold. The cause of a cold is always a virus, and if you’re not exposed to it you won’t catch it no matter how tired or cold you are.

2. Having a high PSA means you have prostate cancer.
An elevated PSA level is associated with an increased risk of having prostate cancer. But simply having a high PSA does not mean you have cancer — there may be other reasons.

3. Reading in dim light permanently damages the eyes.
Some people feel that their vision blurs or they get a headache after reading in dim light. Maybe, but the effects are not permanent. The same is true of watching TV too close to the screen – it does not permanent damage to the eyes.

4. Lack of sleep will kill you.
Even though most people need and should get between seven to nine hours of sleep per night, there’s little evidence that lack of sleep will kill you. Some studies suggest sleeping too little puts extra strain on your cardiovascular system but there has also been at least one study showing that people who sleep too much live shorter lives.

5. Green phlegm means you need antibiotics.
The color of your sputum does not indicate whether or not you need antibiotics. Antibiotics are only used to treat bacterial illnesses, like strep throat and many pneumonias.

6. We need detoxification treatments for health and weight loss.
A healthy body detoxifies itself through the kidneys and liver.

7. The flu vaccine will make you sick.
You most likely will not get sick from the flu vaccine and even if you do, it’s still better than catching the flu.

8. You need eight glasses of water per day.
Hydrating is good but you don’t need eight glasses per day.

Dr. Zach (Zachary Levine) is an emergency physician at the McGill University Health Centre and the medical correspondent for Zoomer Radio (AM740; zoomerradio.ca)