Carotenoids are the clear pigments found in a variety of plants, fungi, algae and bacteria. There are more than 650 species1 throughout the natural world, and there are about 100 of them in our diet.
The body cannot produce carotenoids, so they must be obtained through our diet. You can see them in action in many of the plants already on your plate, including leafy greens, peppers, squash, zucchini, corn, kiwi and grapes.
There are two main types of carotenoids: carotenes and xanthophylls. Xanthophylls contain oxygen; carotenes do not. The most important carotenoids in the context of eye health are xanthophylls, especially lutein, zeaxanthin and astaxanthin.
Lutein & zeaxanthin
Lutein and zeaxanthin are highly concentrated in the macula lutea, a yellow-colored area in the optical center of the retina. These macular carotenoids act as internal sunglasses and filter blue light. Neda Gioia OD, CNS, FOWNS.*
Lutein and zeaxanthin also contribute to night vision and clarity, adds Gioia.* Other research points to lutein’s ability to visual acuity2 And contrast sensitivity3.*
Astaxanthin has been clinically shown to reduce eye strain due to its ability to relax ciliary muscles.*