Omega-3 may reduce glaucoma risk - Optometry Australia

By: Helen Carter
15/02/2018

Eating omega-3 polyunsaturated fatty acids, commonly found in fish and some nuts and plant foods, might help to reduce the risk of developing glaucoma, new research suggests.

The US study in JAMA Ophthalmology said increased daily dietary intake of omega-3s including eicosapentanoic acid (EPA) and docosahexanoic acid (DHA) was associated with lower levels of glaucoma.

The message comes in the lead-up to World Glaucoma Week in March and Glaucoma Australia’s B.I.G Breakfast fund-raiser.

It follows University of Melbourne research which found that increasing dietary consumption of omega-3 fatty acids decreases intraocular pressure by about 25 to 30 per cent, a magnitude comparable to many topical glaucoma medications.

Omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) are both “essential” fats because they are required to sustain health. The modern western diet is high in omega-6 but low in omega-3 and the imbalance of these can lead to health problems.

The US study also found that too much overall PUFAs (omega-6 and omega-3 combined) were associated with serum lipoprotein levels and inflammatory status, and a higher risk of glaucoma.

Combining their key findings, the researchers hypothesised that increasing the proportion of dietary omega-3 while controlling overall daily PUFA intake may be protective against glaucoma.

Eat more fish

They studied data from 3,865 people aged 40 or older who filled in vision health and dietary intake questionnaires and had results from visual field loss detection tests and optic disc photographs.

Increased daily dietary intake of EPA and DHA, commonly found in fish, was associated with significantly lower odds of having glaucoma.

‘Our results indicated that lower levels of EPA and DHA intake were associated with glaucoma,’ the researchers wrote.

However: ‘The odds of having glaucoma were nearly three times as high in participants whose daily dietary total PUFA consumption level was in the second and third quartiles compared with those whose intake was in the first quartile,’ they said.

‘This suggests that even though certain subtypes of PUFAs may reduce the risk of glaucoma, excess PUFA consumption may not.’

The US researchers said more longitudinal studies or randomised clinical trials were needed to extend their findings since a causal association between omega-3 PUFAs or PUFA intake in general and glaucoma risk could not be drawn from their observational study.