Dark leafy greens—kale, collards, arugula, spinach, or any other you like—are rich in the antioxidants lutein and zeaxanthin. Lutein filters damaging short-wavelength blue light (from the B-I-V part of the rainbow) to protect the central part of the retina, which houses the cones that let you see colors. And together with zeaxanthin, it combats the accumulation of free radicals that can lead to cataracts and age-related macular degeneration.