Pistachios
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Pistachios

Pistachios are particularly good for keeping your eyes healthy, thanks to significant amounts of the carotenoids lutein and zeaxanthin, which are stored in the retina and help maintain good vision.

When to grab a handful: Postworkout. Besides helping eyesight, pistachios are loaded with protein, which helps muscles recover. "An ounce has as much protein as an egg," says Upton.