Oily Fish Consumption Halts Eye Disease

Eating two servings of oily fish per week may halt the progression of a major cause of blindness in the elderly, according to a study conducted by researchers from Tufts University and published in the British Journal of Ophthalmology.

Previous research has suggested that a diet high in the essential omega-3 fatty acids that are abundant in oily fish may decrease a person's risk of age-related macular degeneration (AMD) by one-third. In the current study, researchers sought to determine whether a diet rich in omega-3s could also benefit those who already have the disease.

The researchers found that study participants with early AMD who ate a diet rich in omega-3s were 25 percent less likely to have their disease progress to the advanced form.

Among those with advanced AMD who ate a diet high in omega-3s, had a diet with a low glycemic index and took supplemental antioxidant vitamins and minerals, the risk of progression to a more advanced form was decreased by 50 percent. These risk reductions were the same in both "wet" and "dry" forms of the disease.

Low glycemic foods are those that release sugar slowly, in contrast to high glycemic foods such as sugar and simple starches.

Based on their findings, the researchers recommended a consumption of two to three servings of fatty fish per week in both those without AMD and those in the early stages of the disease. They hypothesized that a meal high in omega-3s might alter blood fat levels in such a way as to make them less damaging to the eye.

The researchers did not recommend taking antioxidants vitamins and minerals, however. The study also found that participants with early AMD who took antioxidant vitamins and zinc and also had a high intake of beta-carotene were actually 50 percent more likely to have their disease progress to an advanced stage than those who did not take the vitamins.

This suggests that antioxidants play a more complex role in AMD than previously believed.

Sources for this story include: news.bbc.co.uk.