Edited

It is unlikely that any nutritional supplements or herbs can reverse existing cataracts, although it is possible they might help prevent cataracts from becoming worse.

People with low blood levels of antioxidants and those who eat few antioxidant-rich fruits and vegetables have been reported to be at high risk for cataracts.

Here is what research has shown,

Load up on lutein

Supplement with 15 mg of this healthy antioxidant three times a week to improve vision in cases of age-related cataracts.

Eat plenty of green, leafy, lutein-rich vegetables, such as spinach and kale.

Help maintain antioxidant protection against cataracts by taking 500 to 1,000 mg of vitamin C every day.

Shield your eyes from excessive exposure to sunlight to reduce the risk of oxidative damage leading to cataracts.

Also Vitamin B Complex.

Vitamin B2 and vitamin B3 are needed to protect glutathione, an important antioxidant in the eye. Vitamin B2 deficiency has been linked to cataracts.

Older people taking 3 mg of vitamin B2 and 40 mg of vitamin B3 per day were partly protected against cataracts in one trial.

The major antioxidants in the lens of the eye are vitamin C and glutathione. Vitamin C is needed to activate vitamin E which in turn activates glutathione. Vitamin C levels in the eye decrease with age.

Herbs that may be helpful are Bilberry, the anthocyanosides in it may protect both the lens and retina from oxidative damage.