Omega-3 fatty acid intake is associated with shorter axial length in children, suggesting it protects against myopia, researchers say.

Their population-based study found that those in the lowest quantile for omega-3 polyunsaturated fatty acids (omega-3 PUFAs) intake had, on average, longer axial length than those in the highest quartile (23.29mm vs 23.08mm) after adjusting for factors such as BMI, outdoor time and family history.

The study, published in the British Journal of Ophthalmology, looked at 1005 children aged 6-8 enrolled in the Hong Kong Children Eye Study, of whom 276 had myopia.

A relationship similar to that between axial length and omega-3 intake was also reflected in cycloplegic spherical equivalent refraction.