Drinking water can help you lose weight, according to a nutritionist at Wake Forest University Baptist Medical Center.

“Water can decrease your appetite,” said Mara Z. Vitolins, Ph.D., assistant professor of public health sciences. “It is hard to distinguish between being thirsty and being hungry, so try drinking water and waiting 20 to 30 minutes to see if you’re still hungry.”

Drinking water also may help you cut calories, said Vitolins, who also is part of the Center for Research on Human Nutrition and Chronic Disease Prevention.

“Most people drink sodas, coffee and other such beverages and totally disregard drinking plain water,” she said. “Replacing the higher calorie beverages with plain or flavored water (without added sugar) can significantly reduce calories.”

In addition, most of the beverages with a higher caloric content contain caffeine, Vitolins noted.

“The caffeine acts as a diuretic to set you up for dehydration,” she explained. “By the time you feel thirsty, you already are dehydrated.”

People of all ages need to drink plain water, she added.

“Water is an important nutrient and is vital for a variety of bodily functions and processes, including removal of waste products, carrying nutrients and regulating body temperature,” Vitolins said. “Water helps reduce fluid retention and helps keep bowel functions normal.”

One way to calculate how much water you need is to take your weight in pounds and divide by two; the result is the number of ounces of water you should drink each day, according to Vitolins. For instance, a 100-pound woman should drink 50 ounces of water every day, which is a little more than four 12-ounce glasses or three bottles of water that are usually 16.9 ounces each, she said. A 175-pound man would need five bottles of water, she added.

Drinking plenty of water is as important in the winter as it is during the summer, Vitolins said.

“Most people realize fluid is used to produce sweat, which keeps us cool during exercise and the hot temperatures of the summer,” she explained. “But not as many people are aware that the body also needs water to stay warm. The best way to illustrate this is to think of your car. The radiator needs fluid regardless of the weather.”

However, some people need to speak with their physician prior to increasing water intake, especially those with kidney problems that require fluid restriction, Vitolins cautioned.