Carotenoids are the bright pigments found in a variety of plants, fungi, algae, and bacteria. There are over 650 types1 throughout the natural world, and about 100 of them exist in our diet.
The body cannot produce carotenoids, so they must be obtained through our diets. You can see them in action in many of the plants already on your plate—including leafy greens, bell 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—specifically, 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 out blue light.* Plus, their antioxidant properties counteract oxidative stress this area is susceptible to, given the daily hard work of the eye, explains optometrist Neda Gioia O.D., CNS, FOWNS.*
Lutein and zeaxanthin also contribute to night vision and clarity, Gioia adds.* Other research points to lutein’s ability to boost visual acuity2 and contrast sensitivity3.*
Astaxanthin has been clinically shown to reduce eye strain, thanks to its ability to relax the ciliary muscles.*