Vitamin C is probably the most known vitamin, said to help support overall health in many ways including immune support, having anticancer benefits and reducing the risk of cardiovascular diseases. It is a powerful antioxidant (free-radical scavenger) which removes oxidized waste material in the body. It is a necessary ingredient for many enzyme processes in the body, supporting injury healing, blood vessel health and acts as to filter ultraviolet light within the eye for just a few examples. It is helpful for a wide range of eye conditions including diabetic retinopathy, glaucoma, macular degeneration and cataracts.
In the Adrenal Glands
The highest concentration of vitamin C is in the adrenal glands where it is a critical component of adrenal function. In that capacity, vitamin C is a powerful nutrient to help you handle stress.
In the Eye
The second highest concentration of Vitamin C is located in the eye. Here it again performs in its capacity as a powerful free-radical fighter. Its power to help reduce inflammation is important for conditions like uveitis where inflammation and swelling are problematic. Vitamin C enhances the absorption of lutein, one of the most important carotenoid antioxidants in the eye 1For that reason it is recommended in cases of many eye conditions, including:
- Macular degeneration because it helps lutein absorption,
- Glaucoma because it lowers eye pressure somewhat
- Vitreous detachment because it supports connective tissue health
Helpful in Other Health Conditions
Vitamin C has been found to improve sperm quality2 in infertile men, reducing sperm clotting.3 Vitamin C supports the health of the skin, being an a necessary co-factor in collagen creation. In this regard it is especially relevant for skin problems due to damage from the sun. It supports the immune system, and is important in slowing the aging process. It helps reverse the bad effects of high levels of homocysteine - which damage the cells lining your blood vessel walls4 and protects HDL, the "good" cholesterol5. Vitamin C supports the absorption of iron for those who are iron-deficient.6 In the case of patients with bladder infections, or UTI, vitamin C restricts E. coli growth7 and makes the urine slightly acidic, which is not a friendly environment for bacteria growth. It may be helpful, at low dosage levels, in gout treatment. In the case of diabetes, vitamin C may reduce glycosylation, lower sorbitol and improve glucose tolerance.8
Foods and Supplements Containing Vitamin C
See Vitamin C Foods & Supplements for more information.
1. Lutein absorption is facilitated with co-supplementation of ascorbic acid in young adults, Tanumihardjo, et al, J Am Dietetic Assoc 105:114-18, 2005.
2. Fraga CG, Motchnik PA, Shigenaga MK, et al. Ascorbic acid protects against endogenous oxidative DNA damage in human sperm. Proc Natl Acad Sci 1991;88:11003-6.
3. Dawson EB, Harris WA, McGanity WJ. Effect of ascorbic acid on sperm fertility. Fed Proc 1983;42:531 [abstr 31403].
4. Chambers JC, McGregor A, Jean-Marie J, et al. Demonstration of rapid onset vascular endothelial dysfunction after hyperhomocysteinemia. An effect reversible with vitamin C therapy. Circulation 1999;99:115660.
5. Frei B. Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage. Am J Clin Nutr 1991;54:1113S8S.
6. Hunt JR, Gallagher SK, Johnson LK. Effect of ascorbic acid on apparent iron absorption by women with low iron stores. Am J Clin Nutr 1994;59:13815.
7. Schlager TA, Anderson S, Trudell J, Hendley JO. Effect of cranberry juice on bacteriuria in children with neurogenic bladder receiving intermittent catheterization. J Pediatr 1999;135:698702.
8. See the diabetes page.