Cataracts are a clouding of the lens of the eye. Generally said to be a build-up of proteins, or of protein oxidation in the lens of the eye which gradually becomes crystalline and appears opaque, blocking normal vision.
They are usually associated with aging, however some possible causes for this happening are a large consumption of dairy products, specifically milk, by people who do not efficiently utilize the milk sugar galactose (also see below), which causes a deficiency of B2 (Riboflavin).
Also diabetes, heavy metal poisoning, stress, exposure to radiation, long term exposure to bright sunlight, excess free radicals possibly caused by deficiencies in Vitamins A, C, E, as well as Zinc and Selenium, and the use of steroids can all precipitate the incidence of cataracts.

Treatments to prevent cataracts worsening – and possibly bring about an improvement in sight, would include the following:

–  avoid bright U.V. light – wear sunglasses.
–  avoid rancid foods.
– supplement with anti-oxidants such as Grape seed extracts, Maritime pine bark, Quercetin, Glutathione, Bilberry and Eyebright. Good results can be obtained by using relatively high levels of anti-oxidants, especially Quercetin (try about 400-800mg daily plus Grape seed and extra Vitamin C)
– supplement with Vitamin A, 10,000-20,000 IU daily.
– supplment Vitamin E, 400 IU daily.
– supplement Vitamin C, 3000 mg daily.
– supplement with minerals – specifically Zinc, Selenium, Copper and Manganese. Do not take extra calcium, as there is research that shows that elevated lens calcium levels may occur subsequent to cataract formation. However all minerals are found nicely balanced in Colloidal Minerals (dose 1 tbsp. daily).
See page on ‘Minerals – facts’ and ‘Minerals – why we need to supplement’.
– supplement with B complex plus extra B2 (10mg) and extra B6 (10mg).

Some sources of information also list Tryptophan deficiency as being a cause of cataract formation.

Also attempt to improve circulation to the eye. Herbs that have the action of improving circulation are Ginkgo Biloba, Garlic, Hawthorne and Dan Shen.
Flaxseed oil can also help.

New evidence is showing the importance of Lutein and Zeaxanthin in reducing cataract formation. Spinach (and other green veges) contains a good amount of Lutein. Egg yolks contain both Lutein and Zeaxanthin.

Food enzymes can help to break down the protein build-up, but do need to be used in relatively high doses. See page on ‘Enzymes – facts’.

There is a suggestion that cataracts are due to high intakes of galactose (component of lactose or milk sugar) which is acted on by the enzyme aldose producing a sugar alcohol, which then builds up in the eye resulting in an increased water intake and seriously disrupting the electrolyte balance. This can result in a reduction in the synthesis of soluble proteins in the lens fibre.
A similar suggestion is that an excess of any sugar can cause an excess of sugar alcohols in the lens with the same results. One source said that supplementing with Quercetin can inhibit the enzyme aldose and help reduce sugar alcohol production but it seems a better idea to simply reduce sugar intake!