Just a handful of these fiber and protein powerhouses can keep your engine humming all afternoon. Almonds are rich in magnesium, which helps turn sugar into energy. Studies show eating an ounce of nuts daily helped satisfy appetites without packing on pounds, so don’t worry about the calories—just keep your serving size to about a handful to keep the calorie content down. Get an extra wallop of energy by adding raisins to the mix.

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