It’s easy to want to turn to sweetened foods and drinks, such as soda, for an instant energy surge. The only problem with that is, you’re likely to crash just as fast. Michael F. Jacobson, executive director at the nonprofit Center for Science in the Public Interest, suggests eliminating all table sugar and packaged foods with sugars from your diet for two weeks. That will help your body process sugar more efficiently when you do start eating it again, and it also may diminish your cravings. After that, aim to eat no more than eight teaspoons of the white stuff a day. You can figure out how many teaspoons are in a serving of a food by looking for the grams of sugar listed under “total carbohydrates” on the nutrition label, then dividing that number by four. The easiest way to cut back is to eliminate sweetened bottled iced tea, juice and, especially, sweetened soda: A single 12-ounce can of cola contains 10 teaspoons. Jacobson recommends switching to plain H2O or, if you like the sparkle, flavored seltzer water.

By the time you feel parched, you’ve already lost 1 to 2 percent of your body weight in fluids—enough to increase fatigue and confusion, and spoil your mood, according to recent research. Other signs of dehydration include muscle weakness, headache, dizziness, and lack of perspiration. The Mayo Clinic recommends drinking eight 8-ounce glasses of water a day. That may seem like a lot, but food and beverages composed mostly of water—such as milk, juice, coffee, watermelon and tomatoes—also count towards the quota. If you rarely feel thirsty and excrete colorless or pale yellow urine, you’re probably getting enough fluids.

Next: 12 Free Ways to Feel Better Fast

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