Forget the 8 glasses rule. Even though it’s been popularized in the press, there’s no scientific basis for drinking eight 8-ounce glasses of fluid daily. Sixty-four ounces may be too much for inactive people or far too little for those who exercise or work outdoors. Hydration needs can change daily and are highly individual. One easy, anytime check of hydration levels is urine color. The darker it is, the more likely you’re dehydrated. It’s a more accurate measure of hydration than thirst. Look for a 2-pound weight loss. To gauge if you’re adequately hydrated, the American Heart Association recommends weighing yourself after using the bathroom in the morning. If you’re 2 pounds less than normal, you’re likely dehydrated and should drink before doing anything vigorous. Drink more above 70/70. When the temperature and humidity are both above 70, you enter the dehydration danger zone, the AHA says. Sip frequently from a water bottle, and drink before, during, and after vigorous activity. Stay away from energy drinks. They contain large amounts of sugar and stimulants that can be counterproductive and dangerous. Researchers found that brands with caffeine and the amino acid taurine significantly raise blood pressure and heart rate; if you have hypertension or heart disease, avoid them. More heart-healthy advice: Staying hydrated is just one way to keep blood pressure in the safe zone. See 12 more tips to lower BP naturally. Bottom line: Your blood is 80% water; if you don’t replace what’s lost every day, blood thickens, forcing your heart to work harder and raising your risk of a heart attack.
