High vitamin C dosages of 500 mg may reduce the rick or slow the progression of age-related macular degeneration (AMD) and cataracts. Vitamin C is beneficial for our vision because it:
- improves the antioxidant status of the eye
- is necessary for collagen synthesis
- protects delicate blood vessels of the eye
How much vitamin C for good vision?
The recommended daily intake of vitamin C is 75 mg for women and 90 mg for men. Furthermore, pregnant women need at least 85 mg and lactating women need 120 mg of vitamin C a day. People on medication, smokers, and athletes have even higher needs.
However, higher dosages may be beneficial for good vision. In most cases, a daily vitamin C dose of 500 mg is more than enough for protecting our eyes!
We can get this high dosage by following a plant-based diet. Fruits and vegetables are the best dietary sources of vitamin C.
Also, you can boost your vitamin C intake with supplements! Even dosages higher than 1,000 mg are pretty safe!
How does vitamin C protect the eye?
High levels of vitamin C are necessary for good vision. Actually, vitamin C is concentrated in all eye tissues. Moreover, vitamin C is vital for the health of blood vessels, including the delicate capillaries in the retina of the eye.
Above all, vitamin C is a powerful antioxidant. Antioxidants protect the eye from oxidative stress due to air pollution, sunlight, or smoking!
Actually, antioxidants play a key role in AMD development. According to a study, people at high risk of developing age-related macular degeneration (AMD) who received antioxidants had a 28% lower risk of progression to advanced AMD.
In addition, vitamin C is necessary for the synthesis of collagen. Collagen is the main protein of the body. It provides structure to the eye. Especially, in the cornea and sclera. Low collagen synthesis could be a reason for the development of cataracts.
High doses of vitamin C may reduce the risk of cataracts
There are many studies that have linked high doses of vitamin C and decreased risk of developing cataracts. A daily dose of at least 300 mg of vitamin C seems beneficial for good eyesight.
According to studies, vitamin C intakes greater than 300 mg per day can reduce the risk of cataracts by 70%. On the contrary, daily doses of 120 mg from supplements didn’t significantly lower the risk of developing cataracts.
You may need higher doses of vitamin C, if you smoke, have diabetes, or take drugs. These are risk factors for cataracts, as they deplete the eye’s lens of vitamin C.
Vitamin E is also beneficial for lowering the risk of cataracts. Especially, when combining with vitamin C. Both are powerful antioxidants. We can take safely a daily dose of vitamin E up to 400 IU from supplements.
Vitamin C helps people with AMD
Age-related macular degeneration is closely associated with nutrition. People at high risk of developing AMD can benefit from taking 500 mg of vitamin C a day. This dosage, along with beta-carotene, vitamin E and zinc, can slow the progression of advanced AMD by about 25%.