High omega-3 consumption could provide protection from glaucoma
Identifying possible links between diet and health disorders opens up the possibility of acting on dietary consumption (a modifiable risk factor) as a preventative measure for disease.
According to the World Health Organisation, glaucoma is the second leading cause of blindness worldwide. It is estimated that over 3 million Americans have glaucoma, although only half of them know it; in the most common form of glaucoma (open-angle glaucoma), there are no symptoms to permit its detection. This is why it is advisable to have regular eye tests.
Wang et al., from the University of California, used data from 3,865 participants (≥ 40 years of age) in the National Health and Nutrition Examination Survey (USA) between 2005 and 2008 to assess the association between glaucoma and daily dietary consumption of polyunsaturated fatty acids (PUFAs). Glaucoma was defined following the Rotterdam Study criteria and took into account the results from questionnaires on eye health and diet, lab tests and eye tests.
The results showed that high consumption of omega-3 PUFA (eicosapentaenoic acid and docosahexaenoic acid) is associated with a low probability of developing glaucomatous optic neuropathy, while high total PUFA consumption is linked to a high likelihood of glaucoma.
The authors conclude that an increase in omega-3 PUFA, keeping daily intake of total PUFA under control, could protect against this eye disorder. However, longitudinal studies and randomised clinical trials are required to confirm this hypothesis.