B Vitamins May Lower Risk of Macular Degeneration

Among health concerns for the elderly is vision loss, which is not surprising given that there is a 1 in 3 chance of having some kind of vision reduction by the age of 65. One of the most common vision-related issues is age-related macular degeneration (AMD). The destruction of the macula affects sharp central vision which allows objects to be seen clearly. It affects vision in recognizing people, driving and reading. AMD doesn’t hurt and in some it advances so slowly that little vision change is noticed. In others the disease progresses more rapidly and may lead to a loss of vision in both eyes. Treatment is available for advanced cases of AMD which can slow vision loss, but it will not restore vision. Regular eye exams can detect the problem before vision loss begins, but there is really no protection against the disorder.

A new study may offer some hope in preventing degeneration of the eye. Taking the B vitamins; folic acid (folate), B-6, and B-12 in supplement form may lower the risk of blindness. The study appears in this week’s Archives of Internal Medicine. William Christen, associate professor of medicine at Brigham and Women’s Hospital in Boston was the lead author of the study and said, “This is the first randomized trial to indicate a possible benefit of folic acid, B-6 and B-12 vitamin supplements in reducing the risk of age-related macular degeneration.”

More than 5,000 women over the age of 40 who were part of the Women’s Antioxidant and Folic Acid Cardiovascular Study were randomly assigned either the Vitamin B supplements or a placebo. All of the women declared they did not have macular degeneration at the start of the study. This was a double blind study, meaning neither the subjects nor the researchers knew what was contained in the pills each woman was taking.

The women completed annual questionnaires for seven years to track adherence to the regimen and new diseases. At the end of the study 55 cases of AMD were confirmed in the vitamin group and 82 in the placebo group. The study involved only women, but the researchers believe that it probably applies to all older Americans.
 

High levels of homocysteine, an amino acid, have been linked to a greater risk of age-related macular degeneration, as well as reduced cognitive thinking powers and memory loss. According to Christen it is fairly well established that folic acid, B-6, and B-12 can reduce blood levels of homocysteine.

There are an estimated 1.75 million people with advanced AMD, and 7.3 million are in the early stages of the disease. Christen said that more research is warranted to determine the amounts of vitamins necessary to benefit eye health. The doses in the study were higher than daily recommended doses. The supplements were not found to of any benefit in treating cardiovascular diseases, the original target of the study.

“The study did not include rigorous eye examinations or retinal photos,” said Sophie Bakri, associate professor of ophthalmology, vitreoretinal diseases and surgery at the Mayo Clinic. The macular degeneration diagnoses were obtained by reviewing the participant’s questionnaires and medical records. We need future rigorous clinical trials in other populations according to Bakri.