30 Myths About Healthy Eating You Need To Stop Believing

Coffee is dehydrating.

Yes, coffee is a diuretic (aka, promotes urine production), but it's an extremely mild one. It also has a lot of water in it and therefore actually counts toward your daily fluid intake. The amount it would take to dehydrate you is more than anyone should be consuming in a day—if you have two or three cups daily, your fluid levels will be completely fine.