Limiting liquid calories can fire up your weight-loss plan
America, the home of the Big Gulp, doesn't have a hydration problem. In fact, from the 1980s to the 1990s, we consumed 21 ounces more of fluids a day, while water intake held steady. Here's the catch: We're drinking a greater portion of our calories than ever before. And that has contributed to the current obesity epidemic.
The drinking itself isn't the problem. There's a reason doctors, dietitians, personal trainers, and grandmothers everywhere keep telling us to drink plenty of water: It's essential for the body to function. Water accounts for about 60 percent of the body and is part of every bodily fluid. It helps transport nutrients to your cells, flush away waste, and lubricate your mouth and eyes.
The issue is with our beverage choices. A can of soda has 140 calories. Eight ounces of juice have 100 calories or more. A bottle of beer has 150 calories. Five ounces of wine have 120 calories. And coffee drinks can have upwards of 400 calories, depending on the size. "If you have 2,000 calories a day and you drink 500 calories, then you have only 1,500 calories [from which] to get all of your nutrients," says Benjamin Caballero, MD, PhD, a professor of nutrition and international health at the Johns Hopkins Bloomberg School of Public Health.
Caballero advises curbing your intake of sugar-sweetened beverages like soda, smoothies, and juice drinks. He also suggests limiting energy drinks, alcohol, full-fat milk, and fruit and vegetable juices (you can get the same nutrients with fewer calories by eating whole fruits and vegetables).
Caloric beverages are usually high in carbohydrates, too. A can of Coke has 39 grams of carbs; 8 ounces of Ocean Spray juice have 29 grams; and a venti Starbucks Caffè Vanilla Frappuccino has a whopping 89 grams of carbs. "You need to account for those carbs in terms of raising your blood sugar. And you need to look at the calories," says Bethany Thayer, MS, RD, a spokesperson for the American Dietetic Association and a manager at Henry Ford Health System in Detroit.
The Satiety Problem
At first glance, drinking calories instead of chewing them doesn't seem like a big deal. Calories are calories, right? That's true, but research shows that when mealtime comes around, people don't account for liquid calories they've consumed earlier. "Every scientist in the world will tell you that if you get more calories from beverages, you won't change your food intake," says Barry Popkin, PhD, a professor in the Department of Nutrition at the University of North Carolina's Gillings School of Global Public Health.
Though Popkin says the reason behind this is unclear, there are theories, one of which centers on satiety—or the feeling of fullness. "When you eat something in solid form, there is satiety," says Caballero. "When you eat calories in fluid form, the return to hunger is faster." Because liquids are by nature less filling than solid foods and more quickly digested, the feeling of fullness can be fleeting.
But, says Thayer, the reason may originate in the brain. "There is also a psychological component of eating," she says. "There's the time thing: It takes longer to eat." Your brain may associate fullness with a leisurely meal but not with, say, the two beers you just drained.
Health in the Mix
None of this means you need to chug eight glasses of water during the day. "We get a fair amount of water from foods that we eat," says Thayer. "Fruits and vegetables are a good way to get water, and they help you feel full." Some, like cucumbers, watermelon, lettuce, and celery, have especially high water content.
Other no- or low-calorie drinks count, too. In a 2006 study, Popkin and Caballero ranked coffee and tea high on their list of best beverages. (Water topped the list.) "Coffee drinking may reduce the risk of type 2 diabetes," says Caballero. "Tea has some antioxidant properties. Those in moderation are OK ways to consume liquids throughout the day." (But keep in mind that both often have caffeine; the Food and Drug Administration advises limiting yourself to three to four cups of coffee daily.) Milk, while a good source of nutrients like calcium and vitamin D, can also be high in calories, so pick skim.
As for replacing regular soda with diet, research is divided on whether doing so can lead people to fill in the calorie deficit with food. "Clearly, the reasoning that people suggest is that if you are used to the sweet taste [from diet soda], it will result in you consuming sweet elsewhere," says Caballero. "On the other hand, there are studies of the diet programs that [show that] if you drink diet beverages in the program, you lose more weight than if you consume caloric drinks."
To keep your drinks exciting (not that there's anything wrong with plain old water), try flavoring seltzer water with the juice from a lemon, lime, or orange. Diluting your juice can cut calories, too. "Mix a half cup fruit juice and a half cup water—or a cup, depending on what you like," says Thayer. "You still need to account for the approximately 15 grams of carbohydrates in there." Try pouring a few tablespoons of pomegranate juice into seltzer for a virgin cocktail. Or add flavor to ice water by floating sliced watermelon, peaches, or kiwi in the glass.
When it comes to sipping low-calorie drinks, the payoff is big. In a 2009 study, Caballero found that reducing liquid calories had a greater effect on participants' weight loss over 18 months than reducing food calories did. Plus, the weight stayed off. "Those who complied more lost more. Those who reduced [caloric drinks] less lost less," he says. The same can be applied to your diet: The fewer calorie-packed drinks you have, the more weight you'll drop. Even better, ditching liquid calories may be all you need to kick your weight loss into high gear.