We Use Much More Than 10% of Our Brains

Quote of the day:
"There are some people who would never have fallen in love if they had not heard that there was such a thing."
--Francois VI, duke de la Rouchefoucauld (1655)

Happy New Year!

The new year is a good time to get straight on some deeply-embedded misunderstandings.

We believe many things about health and medicine that are questionable at best, and sometimes downright wrong. The “British Medical Journal” recently published a list of seven things we believe that just ain’t so. It was compiled by Rachel C. Vreeman of the Indiana University School of Medicine an Aaron E. Carroll of the Regenstrief Institute.

1. “You should drink at least eight glasses of water a day.” This advice has been around since 1945, but there’s no scientific evidence to support it. In fact, excessive water drinking can be fatal.

2. “We use only 10 percent of our brains.” Modern medical imaging shows that there’s no region of the brain that is completely inactive.

3. “Hair and fingernails continue to grow after death.” They don’t, but dehydration of the body and retracting skin can make it appear so.

4. “Reading in dim light ruins your eyesight.” It can strain the eyes and reduce blinking (which may cause uncomfortable dryness), but the effects are temporary. There’s no permanent effect on eye function or structure.

5. “Shaving causes hair to grow back faster or coarser.” Numerous studies have shown this to be false. Shaving does remove the finer, tapered ends of hair, which can make the remaining stubble seem coarser. And new hair emerging from the skin can appear darker because it has not been lightened by sun or chemical exposure. But shaving itself doesn’t affect the hair at all.

6. “Mobile phones are dangerous in hospitals.” There’s little real evidence to support the idea that cell phones can interfere with critical medical equipment. All of the evidence cited is anecdotal and pretty dubious.

7. “Eating turkey makes people especially drowsy.” Tryptophan, an amino acid, is involved in sleep and a form of it is marketed as a sleep aid. Turkey contains tryptophan, but so too does chicken and beef. Pork and cheese contain more tryptophan than turkey. Sleepiness after a big turkey meal is more likely due to diverted blood and oxygen flow from the brain to the digesting stomach.

The complete article can be read here.