Laroche's study appeared in the Journal of the Academy of Nutrition and Dietetics.

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Marisa Moore, a registered dietitian with the Academy of Nutrition and Dietetics, says superfoods are healthy, but adding them to your plate won't simply melt the pounds away.

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When you only eat fruit, you're excluding a lot of valuable nutrients from your diet, says Marisa Moore, registered dietician and spokeswoman for the Academy of Nutrition and Dietetics.

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Studies in the Journal of the Academy of Nutrition and Dietetics and the American Journal of Preventive Medicine also support the benefits of journaling, although weight loss in both studies was modest.

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