Vitamin C and Bioflavonoids:
The Batman and Robin of Eye Health

By Gina White; reviewed by Charles Slonim, MD

We talk about vitamin A first in our Nutrition & Eyes section, but it isn't the only antioxidant your eyes need. Another vision superhero is vitamin C. His sidekick, the bioflavonoid, helps him to do his work and does some work of his own, too.

Vitamin C: Vision Superhero

Studies suggest that high levels of vitamin C can reduce the risk of cataracts, which are caused by a buildup of protein that results in cloudy vision. Antioxidant vitamins C and E may also play a role in delaying age-related macular degeneration, which currently has no cure.

As if potential cataracts or macular degeneration weren't reason enough to make sure you get your vitamin C, it may also prevent and alleviate glaucoma. Studies have shown it to reduce pressure in the eyes of glaucoma patients.

So how much vitamin C should you be getting? The U.S. RDA is 60 milligrams (mg) for both males and females. You should absolutely get the RDA every day. Not only are humans unable to create their own vitamin C (unlike most other species), but we also can't store it in our bodies for very long. If you smoke, drink or have diabetes, you should try to take in extra vitamin C, because your levels will tend to be lower than average.

Citrus fruits, berries, peppers, tropical fruits, potatoes and green, leafy vegetables have a lot of vitamin C. Here's a sampling:

The above values are for raw foods. Cooking can change the values, as heat will decrease the vitamin C content. Light is also destructive to C, so if you drink orange juice, it's better to purchase it in opaque plastic jugs or cartons, rather than in glass bottles.

As with vitamin A, foods with C are better fresh than frozen or canned, as either process could deplete the amount of the vitamin.

The Bioflavonoid: Colorful Nutrition Sidekick

Evidence suggests that your eyes also need bioflavonoids, which are sometimes called vitamin P (though they aren't vitamins). They're compounds that give certain foods their color, and they often work as antioxidants. The good news is: almost any food that has vitamin C in it also has bioflavonoids, so there is no extra list of foods for you to eat. Plus, bioflavonoids help your body to absorb C.

Bilberry is the source of bioflavonoids most often touted as being good for your eyes, but it's not very common in the United States. The white part in the center of citrus fruits is an excellent source of bioflavonoids, and you can also get them from red and purple fruits, such as cherries, grapes and plums. Buckwheat is another good source.

You may sometimes hear bioflavonoids referred to by their many specific names, including: quercetin, rutin, hesperidin or the subgroup anthocyanosides.

*Source: National Agriculture Library, U.S. Dept. of Agriculture

[Page updated June 2006]