Let’s face it – water is so dull. But vitaminwater, with its kaleidoscopic pinks, peaches and violets, is like Vegas in a bottle! Vitaminwater’s shimmering hues even seduced rapper 50 Cent, the inspiration for amethyst-tinged Formula 50. But aside from using star power and flashy colors, vitaminwater’s parent company, Glaceau (owned by Coca-Cola), markets the drink by emphasizing its nutritional value. Is there any science behind the marketing though?

A vitamin-fortified drink may sound like a swell idea, but there are two caveats to keep in mind. First, most Americans aren’t vitamin-deficient, according to Marion Nestle, a nutrition professor at New York University. A government survey in 1999 showed that the median American adult man or woman already consumes more than the Recommended Dietary Allowance (RDA) of vitamins thiamin, riboflavin, niacin, B 6 and B 12 , and three-quarters of the RDA of vitamins C, B 9 and A (including carotenes). In fact, vitamin E is the only surveyed vitamin Americans consume at less than half of the RDA – but it’s found in only a third of vitaminwater drinks.

If you want to drink your additional vitamin E, there’s a second caveat: your body may not absorb it. To understand why, it’s important to know that vitamins can be divided into two groups: water-soluble and fat-soluble. Vitamin C and the B complex group are water-soluble and can easily enter the bloodstream with water. Vitamins A, D, E and K are fat-soluble. That means they can only enter the bloodstream to carry out their functions if they are dissolved in dietary fat, like that found in a meal. An Italian study published by the American Heart Association in 2001 showed that subjects who took vitamin E for two weeks on an empty stomach increased their vitamin E concentration in blood little or not at all, compared to an 84 percent increase in subjects who took the vitamin E supplement during dinner. So unless you prefer vitaminwater to wine with your meal, vitamins A and E will pass largely unused into your city’s septic system.

Even if you were to absorb all the vitamins, vitaminwater might have trouble living up to its image as a salubrious alternative to sugary soft drinks: Each bottle of vitaminwater contains 32.5 grams, or two heaping tablespoons, of crystalline fructose. Fructose is a simple sugar that sweetens many fruits, although the crystalline fructose in vitaminwater is produced from cornstarch, not fruit, by crystallizing the fructose in fructose-enriched corn syrups. As one would expect, nobody needs these extra sugars, according to Nestle, the NYU nutritionist. One research team has even indicated that the intense sweetness of sugary drinks may be addictive.

“The way that vitaminwater is marketed and positioned it’s made to look more healthful than other sugary beverages, but it’s not – it’s still just a soft drink,” said Margo G. Wootan, Director of Nutrition Policy at the Center for Science in the Public Interest. “It has this aura of healthfulness that is not deserved. Adding vitamins and minerals to junk food doesn’t make it healthy.”