Hard-boiled eggs (pre-peeled)
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You already know eggs are a great source of protein. Hard-boiled and peeled, they're a portable protein to pack, alongside some crunchy veggies, an apple or whole-grain crackers.

Sugar content: 0 g
Fat: Mostly saturated fat, but the yolk also delivers most of the egg's nutrients, including carotenoids, which help prevent age-related macular degeneration.
Other: 6 g of protein per egg

Where to get it: Gas station; supermarket