LITTLE ROCK — Does the temperature of drinking water affect how quickly your body can use it? Some say that lukewarm water is absorbed more quickly and that cold water helps burn calories. Is that true?
Volume appears to matter more than temperature.
A review of research about hydration during exercise by the American College of Sports Medicine found that the rate at which fluid leaves the stomach depends on a complex interaction of factors. They include the volume of the fluid, its temperature and composition, and exercise intensity.
The review found that the biggest factor was sufficient fluid volume in the stomach. Fluid leaves the stomach for the intestine (where it can be absorbed into the bloodstream) faster when there's plenty of fluid to move.
A high percentage of glucosein the fluid will slow the rate of transfer significantly, so the college recommends that sports drinks contain less than 8 percent carbohydrate.
A big factor in ingesting enough fluid is palatability - whether fluids taste good. Therefore, the college recommends that fluids "be cooler than ambient temperature" - 59 to 72 degrees - and flavored to enhance palatability.
A 2006 study in The Journal of Clinical Endocrinology and Metabolism casts doubt on the idea that cooler water helps burn calories.
In the study, done in Switzerland, resting energy expenditure after drinking cooled, distilled water was measured in healthy young volunteers and compared with the results after they drank room-temperature liquids.
The study found a very small difference, "well below the theoretical energy cost of warming the water to body temperature," and the results "cast doubt on water as a thermogenic agent for the management of obesity."
ActiveStyle, Pages 30 on 08/31/2009