4. drinking water
You may be craving a cup of coffee as soon as your feet hit the floor, but what your body really needs is a glass of water, Ingersoll says. Since you haven't had any liquids in your system for at least six (or hopefully eight) hours, your body is dehydrated. You can have the coffee (see below), but your body will function better—you'll have fewer headaches, less fatigue, and smaller bags under your eyes—if you down a glass of water first, Ingersoll says.
5. ...and coffee
Don't feel guilty about reaching for the coffee pot after you've had your water—it is actually good for your body, too, says Ilyse Schapiro, a Registered Dietitian and Certified Dietitian/Nutritionist. "Coffee is a great source of antioxidants, and it can increase energy as well as help to stabilize our moods," Schapiro says. "It can also help keep our brains healthier and our minds sharper."
Too much coffee isn't going to do you any favors, though. Stick with one or two cups a day, and be consistent with how much you drink, or else you'll start getting headaches and withdrawal symptoms.