It keeps your cells hydrated and helps you burn calories. Reason. Whenever you drink something cold, your body raises your metabolism to keep your body temperature from falling. That process burns calories--eight 16-ounce glasses of ice water will burn an extra 200 calories per day. Strategy. Start the day with eight to 16 ounce of ice water. Sip a 16-ounce glass every hour or two, keeping one next to you at work and at home. Overall, you should drink eight glasses a day. Finish up by 7pm to avoid having to use the bathroom after you go to bed.