Dietary polyunsaturated fatty acids are essential in maintaining the proper structure and function of cell membranes and hence has a role in delaying cataract. In fact animal studies have shown that high intake of polyunsaturated fatty acids delays the onset of cataracts. A cataract is a clouding of the normally clear lens of the eye. Age-related cataract is one of leading cause of blindness in the world today. Besides the physical handicap, cataract also represents enormous economic burden, both to the patient and to the country in terms of the operative procedures it requires.
The association between dietary fat intake and cataract extraction was studied in adult women from the Nurses' Health Study in US whereby nearly 72000 women were followed prospectively for up to 16 years. The study was done from the year 1984 to 2000. Questionnaires were used to assess the fat intake in the diet. Incident cases of cataract extraction were determined by a biennial questionnaire.
The study showed that women who took a high intake of long-chain omega-3 fatty acid had a 12% lower risk of cataract extraction compared with those who took low
fat intake. Another dimension brought out by the study was the relation between fish intake and cataract.
Total fish intake was inversely associated with cataract. This is because of the fish and sea foods contain significant quantities of long chain omega-3 polyunsaturates. The findings from the study suggest that higher intake of long-chain omega-3 fatty acid (eicosapentaenoic acid and docosahexaenoic acid) and consumption of fish may modestly reduce the risk of cataract. Previous studies had shown that diets high
in fish are associated with reduced CHD risk because fish oils and omega-3 fatty acids result in decreased triglycerides and increased LDL-Cholesterol and/or
apolipoprotein B level(s).
This is really some good news about for the fish lovers to cheer about!
For the hard core vegetarians rest assured a type of omega-3 fatty acids is also present in tofu and other forms of soybeans, canola, walnut and flaxseed and
Reference:American Journal of Epidemiology 2005 161(10):948-959; doi:10.1093/aje/kwi118