10 body myths debunked by science

Myth 1: Calories Counting Is All That Matters for Weight Management – Calories are the energy content as measured by complete combustion of the food. But, our bodies don’t burn food, they digest, ingest and metabolise it, so different foods even if they have the same “calories” can have a very different effect on our bodies.

Myth 2: Body Hair Grows Back Thicker When You Shave It – Nope. It doesn’t.

Myth 3: You Need Eight Hours of Sleep Per Day – Well, some people do, others need more and some kind survive on half that or less with no apparent ill effects.

Myth 4: Reading in Dim Light Ruins Your Eyes – it can “strain” your eyes, tiring them, but there’s no permanent damage to vision or the structure of the eye even from nightly reading in dim light.

Myth 5: Urinating on a Jellyfish Sting will Sooth the Pain – You should rinse with vinegar or seawater. Ammonia solution, urine and alcoholic preparations can cause the nematocysts (stinging cells) embedded in your skin to fire, making things worse.

Myth 6: Your Slow Metabolism Makes You Fat – It’s obviously not true. The bigger you are the more calories you burn to keep going, that’s a higher basal metabolism than someone lean who burns fewer calories and so has a lower basal metabolism.

Myth 7: You’ll Catch a Cold from Cold (and Wet) Weather Conditions – Nope. Colds are caused by viral infection not by snowballs and wet feet.

Myth 8: More Heat Escapes Through Your Head – Heat does escape through your head, but the rate of heat loss is the same as from any other area of your skin, it’s just that unless you usually wear a hat it’s the bit most often uncovered and so putting a hat on will reduce total heat loss.

UPDATED Myth 9: High Cholesterol Causes Heart Disease – The picture is complicated, there is some evidence that a raised level of an entirely different compound, homocysteine is a better indicator of risk. Of course, deposits of the waxy cholesterol and other lipid within the lining of the arteries that supply the heart does cause heart problems. Actually, it’s not strictly true to say that cholesterol doesn’t cause heart disease. You can be perfectly healthy with high cholesterol, but if waxy deposits form on the inside of the arteries supplying your heart and elsewhere then that’s not good, but this is not a given. if you’re arteries are chocked with lipids then that will raise your blood pressure. But not all hypertension is caused by that. Blood pressure can be higher than “normal”, just because that’s your body’s operating pressure.

Myth 10: It’s Dangerous to Wake a Sleepwalker – The reverse is probably true as a sleepwalker is more likely to trip and fall downstairs or wander off. They might get a shock when you wake them, but a shock isn’t likely to do much harm.

Adapted from a recent Lifehacker post: 10 Stubborn Body Myths