Good advice for overall ocular health and maintenance.
By James P. Meschino, DC, MS
A study published in the July 2013 issue of the American Journal of Clinical Nutrition adds to the evidence suggesting certain B vitamins may be important in the prevention of age-related macular degeneration (AMD), which is the leading cause of vision loss in people over 55 years of age in the U.S. and Canada. Previous studies have shown that taking certain antioxidant vitamins and minerals as supplements (vitamin E, vitamin C, beta-carotene, selenium and zinc), at specific dosages, can slow the progression of AMD.
In the latest study, known as the Blue Mountain Eye Study, serum folate (B-vitamin folic acid), vitamin B12 and homocysteine status were determined from blood samples drawn in 1997-1999 from cohort members ages 55 and older. AMD was assessed in 1,760 survivors from retinal photographs taken in 2002-2004 and 2007-2009. Total intakes of folic acid and vitamin B12 were assessed using a food-frequency questionnaire.
Results showed that higher blood levels of homocysteine were associated with a significant increased risk of developing AMD, whereas higher levels of vitamin B12 were strongly associated with decreased risk of developing AMD. Homocysteine is a toxic end-product of metabolism known to damage blood vessels and increase the risk of cardiovascular disease. Studies continue to show that high blood levels of homocysteine also contribute to damage seen in AMD.
People with folate or vitamin B12 deficiency at the beginning of the study (baseline) were approximately twice as likely to develop AMD during the 10-year study period.
eyesight What is important is that homocysteine levels are reduced via supplementation with, and dietary intake of, vitamin B12 and folic acid. These B vitamins recycle homocysteine back to the nontoxic and highly useful amino acid known as methionine. This explains why high levels of serum homocysteine, and low levels of vitamin B12 and folic acid, are so strongly linked to the development of AMD, as confirmed in the Blue Mountain Eye Study… >READ MORE<