You can call them string beans, snap beans or green beans, but no matter which name you prefer, they’re all the same fat-free, low-calorie vegetable. The little beans tucked inside their edible pod are a good source of cholesterol-lowering fiber, but they’re an even better source of several vitamins that contribute to healthy eyes and bones. Even though they don’t show it, string beans contain the same pigments that give vegetables their red, yellow and orange colors. These pigments, called carotenoids, all function as antioxidants, but some also fill other roles. String beans contain three carotenoids: beta-carotene, lutein and zeaxanthin. Beta-carotene is converted into retinol, which is the form of vitamin A essential for normal night vision. Lutein and zeaxanthin absorb blue light, which protects your eyes from damage caused by this high-intensity light. Carotenoids are included in the recommended dietary allowance for vitamin A. You’ll get 29 percent of your daily allowance ...
