Mythbusters
I know some of us here are fans of the show Mythbusters. For those that don't watch it, the premise of the show is to take some kind of myth people have and run an experiment to debunk or prove the myth. Not always are their "proofs" very encompassing, but they are usually entertaining.
In the spirit of Mythbusters, I want to point out some common misconceptions as well (although I won't be doing any cool experiments to disprove it).
Water
Water is over-hyped. :) Apparently, the drink "8 8-ounce glasses of water everyday" that you hear many nutritionists and even doctors say is not necessarily based in scientific fact. It doesn't HURT to drink that much water... but generally rule of thumb is to drink when you are thirsty. Someone who works out is going to need a lot more than someone who is inactive. Also, it appears that pops, coffee and teas with caffeine don't dehydrate but alcohol can. The amount of caffeine in those products don't really outweigh the liquid contained in them.
Of course, like everything, you must be wary and not take it as gospel. It doesn't hurt to drink water... so really whatever habits you have, as long as you feel healthy and hydrated... you are probably fine. Here is another article about the subject.
Hair Myths
It's interesting how many hair myths there are out there. This site and this site very simply state some of these myths... but if you are so inclined... there are literally hundreds of articles out there with a lot more detail about the myths. I thought some of them were interesting. One is if you cut hair, it grows back faster. Another one is if you shampoo your hair with the same shampoo over and over, your hair gets use to it. Also the fact that you inherit baldness from your mother's side of the family (to which my younger brother disproves that myth). All are very interesting.
We Use 10-Percent of our Brain
I've always had an issue with this one and a year after high school I read an article in Scientific American that completely disproved this common myth. This Snopes article gives a little bit of background and information on why the myth exists and why it's wrong. Yay for not being 90% brain-dead!
Anyway, what are some myths you know a lot of people believe yet you know to be false?