Hey health freaks: We hear you over there touting the relative benefits of superfoods, shouting from the hilltops how much you love stuff like kale and acai berries. But guess what? The truth is, some of these so-called superfoods may not be as healthy as we thought.

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Which is not to say that they're not healthy. Of course kale is good for you. But if you really want to get the most out of your dark leafy greens, scientists are now saying that you should reach for romaine over kale. In a new study, researchers analyzed the nutritional content of 47 fruits and vegetables and ranked them according to how much fiber, protein, potassium and vitamins and minerals they contains.

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Watercress topped the list, followed by Chinese cabbage, chard, beet greens and spinach. Kale came in 15th, behind a bucketload of other types of greens, include parsley, collard greens, endives, mustard greens and chicory. The least nutrient dense veggie on the list? Grapefruit. Sweet potatoes, leeks, and blackberries also scored low.

Of course, it should be noted that eating any and all of these fruits and veggies is probably better for you than eating virtually any other kind of food. So take note, but please, feel free to eat a fistful of kale anyway. [Reviewed.com]