Keep your eyes healthy: eat organic food

Abstract

Healthy eyes provide good vision, which is essential for a productive lifestyle.¹ Importantly, there is a substantial amount of literature demonstrating the prophylactic role of optimal nutrition on visual health.^1,2 Thus, evidence suggests that dietary patterns, including fruits and vegetables, are essential for eye and vision health.^1,2 With these considerations in mind, it is worth highlighting the convenience of the excellent review article by Hu et al,³ published in this journal in 2023. In brief, the authors clearly demonstrated that an adequate dietary intake of xanthophyll-rich food or supplements can improve eye health.³ Their article also merits reflection on the use of pesticides in food and their impact on eye and visual health.

Lately, agriculture has started to become dependent on the (synthetic) chemical industry, which produces patented fertilizers, pesticides, and seeds.⁴ Unfortunately, there are several adverse health effects associated with exposure to chemical pesticides, such as dermatological, respiratory, reproductive, endocrine, obstetric (child growth), carcinogenic, gastrointestinal, and neuropsychiatric consequences.⁵ The current situation is similar regarding eye health.

Classically, exposure of unprotected eyes to pesticides results in the absorption of these products into ocular tissue and potential ocular toxicity.⁶ The most described effects of pesticides on eyes are irritation, burning sensation, itchiness, blurring of vision, and watering of eyes.⁶ Furthermore, it is also important to point out that long-term ocular exposure to pesticides may produce chronic effects in the eyes.⁶ Considering these data, it has been established that protection of the eyes is a major component of public health and preventive medicine.⁶ In parallel, another concern must be evaluated by scientists: contact with pesticide residues in food can lead to acute exposure poisoning or long-term eye health problems. In fact, there is a substantial amount of translational literature demonstrating that chronic exposure to chemical pesticides in food is associated with the decreases in refractive error and corneal curvature suggestive of myopia and increased intraocular pressure.⁷ Furthermore, pathological lesions have been reported, including demyelination and separation of the nerve fibers in the optic nerve and extraocular muscle, partial necrosis of pigmented epithelial cells, cytoplasmic edema, and degeneration of myofilaments in the ciliary muscle.⁷

According to the inspiring study by Hu et al,³ the presence of pesticide residues in major xanthophyll-rich food sources is something we should pay attention to. Dietary sources of xanthophylls include lutein and zeaxanthin in green leafy vegetables and corn, and β-cryptoxanthin in pumpkins, papayas, and peppers.⁸ The minor xanthophylls astaxanthin and canthaxanthin are found in certain fish and seashells and in certain mushrooms.⁸

CONCLUSION

Putting all these data together, what should be the guidance? First, scientists should encourage people to adopt healthier behaviors to reduce health risks.⁹ One goal is to promote organic food consumption in direct relation to a healthy lifestyle.^4,5,10 Along with the need for more clinical trials, it is important to consider the consumption of organic food because this substantially reduces consumers’ dietary pesticide exposure, as well as acute and chronic risks of such exposure. Although organic food tends to be more expensive than conventionally produced food, organic products are healthy and contribute to the preservation of the environment and the appreciation of agro-ecologically oriented family farming. Finally, the first important requirement is to educate the population to consume healthy foods. Meanwhile, it is important to limit intake of pesticide residues by peeling or washing fruit and vegetables, which also reduces other hazards, such as harmful pathogens.

Acknowledgments

The authors’ studies are supported by grants from the following: Fundação de Amparo à Pesquisa do Estado de São Paulo; Conselho Nacional de Desenvolvimento Científico e Tecnológico and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, and Fundação de Amparo à Pesquisa do Estado de Minas Gerais.

Funding. No external funding was received to support this work.

Declaration of interest. The authors have no relevant interests to declare.

Author contributions. F.A.S. conceived of and wrote this letter. J.F., L.B., L.M.B., and A.-C.G.dA. read and approved the final version.

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