Oprah Winfrey recently wrapped a "21-day cleanse"—a strictly vegan diet (think tofu scramble and tempeh scallopini) with no caffeine, sugar, gluten or alcohol for three weeks! Cate Blanchett also tried a 21-day detox of soy, legumes, lean protein, brown rice and steamed veggies...drizzled with olive oil. Is the "cleanse" a whole lot of hogwash? "Nature has provided us with perfect cleansers—our lungs, liver, kidneys and skin," says Dr. Madelyn Fernstrom, the Today show's diet and nutrition editor. "There are no bad foods—just bad portions." While Oprah's plan is healthy—focusing on fruits, veggies and lean protein—it won't "cleanse" her body any more than a less-restricted diet. "This is more about mental cleansing—discipline and focus," says Fernstrom.

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