11 Ways to Get Prettier, Healthier Skin in Just 1 Week

You've been hearing this bit of advice since grade school, but it's really good advice! "Drinking water is a lifetime good habit," said Dr. Downie. "For every one cup of coffee or tea you drink, you should compensate with two eight-ounce glasses of water, as caffeine dehydrates you."

You'll start feeling better right away, with max effects really taking place within three months, she said. Having a stylish water bottle on hand — like this S'Well Mother of Pearl ($35) number — can help keep you motivated and on track!