B-Vitamins may Help Prevent AMD

A recent study suggests that supplementation with B-vitamins may help prevent age-related macular degeneration (AMD), the leading cause of blindness in older Americans.

The study, funded by the National Institutes of Health and published in the Archives of Internal Medicine, included 5,205 women older than 40 years of age who did not have signs of AMD. The women were part of a large study looking at the effects of vitamins in women with heart disease or at least three risk factors for heart disease.

In April 1998, the participants were randomly assigned to receive supplementation (2.5 milligrams of vitamin B9 (folic acid), 50 milligrams of vitamin B6 and one milligram of vitamin B12) or placebo daily. Therapy continued through July 2005, and participants were monitored for the development of AMD through November 2005.

The authors found that women in the supplementation group had a 34 percent lower risk of developing AMD and a 41 percent reduced risk of developing AMD with significant vision loss compared to those in the placebo group. According to the authors, these protective effects were observed about two years after treatment started.

While the potential mechanism of action for these effects is unclear, these B-vitamins have been shown to lower blood levels of the amino acid homocysteine. Elevated levels of homocysteine are associated with an increased risk of developing coronary artery disease (CAD) and have been suspected of damaging blood vessels. However, it is unclear if reducing homocysteine levels would have beneficial effects on the heart.

Although these preliminary results are promising, additional studies are needed before conclusions can be made.

For more information about B-vitamins, please visit Natural Standard's Foods, Herbs & Supplements database.

Comments

[Kristal]

I'm surprised that vitamin B supplementation alone could have such an effect on reducing the risk of developing AMD. It would be interesting to know if the participants were taking anything else or if they made changes to their diet.

[MHD]

The NIH suggests that a lack of vitamin B in the diet can produce neurological damages, leading to numbness in the hands and feet and in the most severe cases, dementia in older adults. Knowing that, it seems logical that vitamin B deficiency could also affect AMD through sensory nerve degeneration. Currently, the NIH also suggests that the greatest risk factors for age-related macular degeneration are obesity, smoking, race, family history and gender. Additional research about vitamin B could produce some very useful findings for patients at risk for AMD.

[TN]

I think MHD brings up a good point in how logistically vitamin B deficiency may be linked to AMD. However, do we actually have solid data and conclusive evidence that vitamin B actually plays a role in nerve degeneration? When more data come out, this may offer great news because specific patient populations, such as diabetics, may greatly benefit since certain types vitamin B may also help with diabetic neuropathy.

[nmh]

This study is certainly interesting. When associated with eye health, I myself usually think about vitamin A. And since the study only investigate B9, B6 and B12, I wonder if the other B-vitamins would have similar effects on AMD. This study shows the importance of sufficient nutrient intake to maintain good health.

[frances]

I think this study is refreshing because we have been hearing a lot about the importance of vitamin D to prevent age-related health problems. This is another reason for people to focus on their eating habits. A full nutritious meal -- as mom used to say -- would do you good!

[AJ]

This study reinforces the idea why we should all take a MVI daily!

[Unsure]

Was there a study out recently that showed that multivitamins (MVI) and/or other supplements proved to be ineffective or showed no concrete results in improving health? Bold statement, yes, but I do not recall where or when this study was published.

[Rachael]

I agree with the comment posted by nmh that people mainly hear about the importance of vitamin A and not the B vitamins in eye health. One proposed mechanism of AMD is that the photoreceptors in the retina are affected by oxidative stress, which causes damage. As a result, it has been suggested that antioxidants may prevent cellular damage. However, a 2000 review conducted by Evans et al. demonstrated that antioxidants do not prevent the onset of AMD.

[Stacy]

There may be a correlation between high levels of homocysteine and the development of age-related macular degeneration (AMD). There is a study from 2006 in the American Journal of Ophthalmology that states that homocysteine is a modifiable risk factor for AMD. As a result, one can deduce that since folic acid and vitamins B6 and B12 break down homocysteine, they may help prevent the development of AMD.