FATwater promises better hydration, energy, even weight loss, but our expert isn't convinced the bottled water lives up to the health hype
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Fat phobia is officially a thing of the past. Nostalgia lovers can shelve it with their scrunchies, Cranberries CD, and other '90s goodies. What makes us so certain? Because fat in water is now a thing.

FATwater is the latest offering in sports drinks. At first glance, it looks like a regular Gatorade alternative: bright colors, fruity flavors, sweetened with sugar-free xylitol. But the secret ingredient in this drink is emulsified fat. (Should You Ditch Your Sports Drinks?)

Invented by drinkable fat trendsetter Dave Asprey, who previously created bulletproof coffee (which calls for adding two to four tablespoons of butter and coconut oil to your morning joe), FATwater has two grams (about 20 calories worth) of Asprey's proprietary coconut oil, Bulletproof XCT oil. According to Asprey, this recipe combines the health benefits of medium-chain fatty acids with all the power of good old H2O for a drink that will supposedly give you energy, help you lose weight, and generally make you feel better.

"The water looks kind of iridescent, pearlescent. It has these tiny, invisible droplets of fat that your body really, really likes," he said, adding that the nanoparticles of fat bring the water into the cells more effectively. "Drink a glass of water, and some of it will absorb and some of it won't. But when your body sees that fat, it says, 'Oh, come on in, this is pure energy.' It brings the water in with the fat and you get a little bump of energy." The bottle further explains that XCT oil follows "a special metabolic pathway to burn fat instead of storing it, giving your body the clean, high quality fuel it needs-and nothing else." (Check out 5 Signs of Dehydration-Besides the Color of Your Pee.)

But is all the hype legit? Can fat water really make you thin (and keep you hydrated)?

Probably not, says Regina Druz, M.D., an integrative cardiologist who specializes in diet and how fats are metabolized. While she says it's true that high-quality, non-toxic saturated fats in food (like those in grass-fed beef and pastured eggs) are not the dietary demons we once believed, mainlining them straight still isn't good for you. And she's very dubious of drinking them.

"One of the main benefits of saturated fats is that they're filling, so I don't see any advantage to adding them to water as that won't increase the satiety effect," she says. The issue she takes with Asprey's formulation is that fats need food to be properly absorbed, debunking his spiel on improved intake. While she does encourage women to eat a serving of fat after a workout, she says it should be as part of a whole, balanced meal that includes plenty of protein-the way fat comes in nature. (Here are 10 Powerful Healthy Food Pairings.)

The other problem, she explains, is that fat and water are digested differently. "Water is absorbed in the intestines, by a process called osmosis. This is passive and doesn't require any energy," says Druz. "But fat requires a special transport system that requires energy to digest it-not only is it not giving you a boost of energy, but it requires energy to burn it off, so the energy claim doesn't really make sense, biologically speaking."

She also says the idea that FATWater is more hydrating is problematic, since water surrounded by fat will actually be harder to absorb in the body. "Water is the gold standard beverage-it's already bulletproof. It's so essential to life that you really can't make it better," she says. "If you're thirsty, just drink water." (Beat the boredom with these 8 Infused Water Recipes to Upgrade Your H2O.)