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On tap

You’ve heard it time and again—staying hydrated is important. But all fluids are not equal. American adults consume an estimated 21 percent of their daily calories from liquids—up from about 14 percent in the 1970s. And because beverages don’t satisfy or fill you up the same way solid foods do, not accounting for these liquid calories may play a role in the alarming rise in obesity.

Last year, a panel of nutrition experts released the first Healthy Beverage Guidelines to help consumers make smarter choices to quench their thirst. The panel ranked beverages in six levels—from best to worst—based on the beverage’s content of sugar, fat, caffeine and calories, as well as effect on overall health. Adults should:

  • drink 98 ounces of fluids a day (that’s more than 12 eight-ounce servings)
  • limit liquid calories to no more than 10 percent of their total daily calories

Follow these guidelines to drink up and stay healthy:

Level 1: Wonderful water

As long as you’re eating a healthy diet, water can meet all your fluid needs. Water is necessary for proper metabolism and physiological function and may provide some essential minerals such as calcium, magnesium and fluoride.

Your daily allowance: At least four to six servings, or 32 to 48 ounces. Drink more water if you limit other beverages.

Level 2: Time for tea (and coffee, too)

Coffee may offer some limited health benefits related to lower risk for type 2 diabetes and colorectal cancer. Tea (black, green and oolong) provides a variety of flavonoids and antioxidants as well as a few micronutrients and amino acids. Tea drinkers may benefit from enhanced immune function and bone density as well as have less tooth decay and kidney stones than people who don’t drink tea. Both contain caffeine, however, which should be limited to less than 400 milligrams (mg) daily—less than 300 mg for women who are pregnant or breastfeeding.

Your daily allowance: Enjoy up to five servings or 40 ounces of unsweetened tea or up to four servings or 32 ounces a day of unsweetened coffee. Iced or hot, the caffeine and whether you add sugar to your cup will limit how much you should drink.

Level 3: Milk matters

As a source of vitamin D, calcium and protein, low-fat and nonfat milk can contribute to a healthy diet, but they aren’t essential. Fortified soy milk is a good alternative for people who prefer not to drink cow’s milk. If you have trouble digesting lactose, you may tolerate yogurt drinks better, but don’t forget to count those calories. Avoid whole milk altogether. Although it contains protein and calcium, too, the extra calories and saturated fat outweigh these benefits.

Your daily allowance: Up to two servings or 16 ounces of low-fat, nonfat or soy milk beverages.

Level 4: Diet drinks

Noncaloric, artificially sweetened beverages like diet sodas and teas and other artificially sweetened drinks are better than the “regular” or sugar-sweetened versions because they contain few, if any, calories. But they don’t offer any benefits, either. The FDA-approved noncaloric sweeteners are considered safe, although some studies suggest that diet drinks may condition you to have a higher preference for sweets.

Your daily allowance: You can have up to four servings or 32 ounces.

Level 5: Juice jives

Drinks that contain calories but still offer some benefits include fruit and vegetable juices. While they provide most of their natural source’s nutrients, even 100-percent juices like orange or tomato lack the fiber and other beneficial compounds you’d get from eating the whole fruit or vegetable. Fruit cocktail drinks usually contain more sugar and fewer nutrients than 100-percent juice. Vegetable juices usually have fewer calories than fruit juices but significant amounts of added sodium.

Your daily allowance: Up to one serving or eight ounces of 100-percent fruit and vegetable juices.

Other caloric beverages that may offer some health benefits included in level 5 are:

  • Sports drinks. These were designed for endurance athletes who need to replace electrolytes such as sodium, chloride and potassium lost during endurance activities. Although you can get the same ingredients from a well-balanced diet, the carbohydrates, water and sodium may benefit athletes during times of excessive fluid loss through sweating or when strenuous exercise lasts longer than 60 minutes.

    Your daily allowance: Consume sports drinks sparingly except for endurance athletes, who should have no more than two servings or 16 ounces a day.

  • Alcoholic beverages. When consumed in moderation, wine, beer or distilled spirits may have some health benefits, including reduced risk of cardiovascular disease, type 2 diabetes and gallstones. But even moderate intake of alcoholic beverages has been linked with increased risk of birth defects and breast cancer. Pregnant women should not drink alcoholic beverages at all.

    Your daily allowance: If you don’t drink alcohol, don’t start. Otherwise, limit yourself to one serving for women and two servings for men. (One drink equals 12 ounces of beer, 5 ounces of wine or 1.5 ounces of distilled spirits.)

Level 6: Empty calories

Caloric beverages that don’t provide any nutritional benefits include soft drinks, sweetened teas and coffees and other beverages sweetened with high-fructose corn syrup or sucrose. They’ve been linked to dental problems, weight gain and type 2 diabetes.

Your daily allowance: If you indulge at all, keep it to no more than one serving or 8 ounces.

The bottom line: Be mindful of all the calories you’re consuming in both your food and your drinks. And remember that you have plenty of no- or low-calorie drinks to quench your thirst, including the best option of all—a good old glass of water. To view the complete beverage guidelines, visit