(CNN) -- Pushing her meal cart into the hospital room, a research assistant hands out tall glasses of reddish-pink liquid, along with a gentle warning: "Remember, you guys have to finish all your Kool-Aid." One by one, young volunteers chug down their drinks, each carefully calibrated to contain a mix of water, flavoring and a precisely calibrated solution of high fructose corn syrup: 55% fructose, 45% glucose. The participants are part of an ongoing study run by Kimber Stanhope, a nutritional biologist at the University of California, Davis. Volunteers agree to spend several weeks as lab rats: their food carefully measured, their bodies subjected to a steady dose of scans and blood tests. At first, each volunteer receives meals with no added sugars. But then, the sweetened drinks start showing up. For the final two weeks of the study, volunteers drank three of the sweet concoctions daily -- about 500 calories of added sugar, or 25% of all calories for the adult women in the study. Within just two weeks, their blood chemistry was out of whack. In one striking change, the volunteers had elevated levels of LDL cholesterol, a risk factor for heart disease. While force-feeding junk food may sound extreme, this controlled diet is not so far from the real world. A 20-ounce regular soda contains 227 calories, according to the U.S. Department of Agriculture (USDA). That single drink is more than 10% of the total calories an adult woman needs to maintain a healthy weight, according to USDA diet guidelines. Meanwhile, about 1 in 4 Americans gets at least 200 calories a day from sugary drinks. These numbers, along with work like Stanhope's, gives ammunition to doctors and public health officials who say soda should be treated as public health enemy No. 1. Soft drinks: Public enemy No.1 in obesity fight? - CNN.com -------------------- Coke is more popular in India than US, More people drink coke than in US.. Coke does do damage, But its really hard to get rid of it in Summer..