Omega-3 Intake Linked to Lower Myopia Risk in Kids

A study published in the British Journal of Ophthalmology suggests that a diet rich in omega-3 fatty acids, commonly found in fish oils, may help reduce the risk of developing myopia (shortsightedness) in children. Conversely, a high intake of saturated fats, such as those found in butter, red meat, and palm oil, may increase the likelihood of the condition.

Rising Prevalence of Myopia and the Role of Diet

Myopia is a growing global concern, particularly in East Asia, with projections estimating that half of the world’s population will be affected by 2050. While environmental and genetic factors such as excessive screen time, limited outdoor exposure, and family history have been widely acknowledged, the role of dietary influences has remained unclear, especially in human studies.

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) are known for their role in preventing various chronic ocular diseases, including dry eye and age-related macular degeneration (AMD). However, their relationship with myopia had not been demonstrated in population-based studies, until now.

Study Design and Methodology

Researchers examined 1,005 Chinese children aged 6 to 8 from the Hong Kong Children Eye Study, a population-based cohort tracking ocular development and risk factors. Children’s dietary habits were assessed using a validated food frequency questionnaire completed by their parents, covering 280 items across 10 food groups.

Nutrient intake, including omega-3s, saturated fats, vitamins, and minerals, was calculated, and lifestyle habits such as outdoor activity, screen use, and near work were recorded. Eye measurements included axial length (a structural marker of myopia progression) and cycloplegic spherical equivalent (SE) (a measure of refractive error).

Key Findings

• 27.5% of the children (n=276) were found to have myopia.

• Children in the highest 25% of omega-3 intake had significantly shorter axial lengths and lower myopic refractive error compared to those in the lowest 25%.

• In contrast, children with the highest saturated fat intake showed the longest axial lengths and highest myopic refractive errors.

• No significant associations were found with other nutrients.

These findings remained consistent even after adjusting for variables such as age, sex, BMI, parental myopia, and time spent on near work or outdoors.

Potential Mechanism and Limitations

Researchers propose that omega-3 fatty acids may help prevent myopia by enhancing blood flow in the choroid, a vascular layer responsible for nutrient and oxygen delivery to ocular tissues. This may reduce scleral hypoxia, a condition linked to myopia progression.

However, the study has limitations. As an observational study, it cannot establish causality. Furthermore, reliance on self-reported dietary intake and the absence of biomarker validation from blood samples may limit accuracy. The high local prevalence of myopia in Hong Kong may also affect the generalizability of findings to other populations.

Conclusion

“This study provides the human evidence that higher dietary ω-3 PUFA intake is associated with shorter axial length and less myopic refraction, highlighting ω-3 PUFAs as a potential protective dietary factor against myopia development,” the researchers concluded.

While further clinical and interventional studies are needed, these findings underscore the potential role of dietary strategies in myopia prevention, particularly the importance of omega-3-rich foods in early childhood.

Reference:

Dietary omega-3 polyunsaturated fatty acids as a protective factor of myopia: the Hong Kong Children Eye Study, British Journal of Ophthalmology (2025). DOI: 10.1136/bjo-2024-326872