Although cataracts are not completely preventable, their occurrence can be delayed. Quitting smoking, avoiding overexposure to sunlight, avoiding excess amounts of alcohol are important protective measures, and eating plenty of fresh fruits and vegetables may delay the formation of cataracts. No existing evidence suggests that using eye drops or ointments or performing eye exercises will stem the onset of cataracts.
The simplest and most effective way to protect against ultraviolet (UV) radiation is to stay out of the sun. Wear a hat and cover-up outside, particularly when the sun is most intense (10 a.m. - 3 p.m.). A wide-brimmed hat can significantly reduce eye exposure to UVB radiation. Because the sun's rays are highly reflective, sitting in the shade or under an umbrella by itself does not guarantee protection.

Note: Avoidance of the sun should not be taken to extremes. Some sunshine is desirable. Moderate sun exposure provides an important source of vitamin D, which is essential for healthy bones and other health factors.
Sunglasses. Protective sunglasses do not have to be expensive. But it is important to select sunglasses whose product labels state they block at least 99 percent of UVB rays and 95 percent of UVA rays.
Polarized and mirror-coated lenses do not offer any protection against UV radiation. It is not clear if blue light-blocking lenses, which are usually amber in color, provide UV protection.
It is not clear whether nutrition plays a significant role in cataract development. Dark colored (green, red, purple, and yellow) fruits and vegetables usually have high levels of important plant chemicals (phytochemicals) and may be associated with a lower risk for cataracts.
In analyzing nutrients, researchers have focused on antioxidants and carotenids. Studies have not demonstrated that antioxidant vitamin supplements (such as vitamins C and E) help prevent cataracts. Still, fruits and vegetables containing these vitamins are important for overall good health.
Lutein and zeaxanthin are the two carotenids that have been most studied for cataract prevention. They are xanthophylis compounds, which are a particular type of carotenid. Lutein and zeaxanthin are found in the lenses of the eyes. Some evidence indicates that xanthophyll-rich foods (such as dark green leafy vegetables) may help retard the aging process in the eye and protect against cataracts. However, there is not enough evidence to suggest that taking supplements with these carotenoids lowers the risk of cataract formation.
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