REVIEW PAPER
Impact of vegetarian and vegan diets on visual acuity and ocular health – a literature review
1
Doctoral School of the Medical University of Lublin, Polska
2
Medical University of Lublin, Racławickie 1, 20-059 Lublin, Polska
3
Medical University, Lublin, Poland
4
POWIATOWE CENTRUM
ZDROWIA SP. Z O.O.
W KARTUZACH
Corresponding author
Dominika Kuźmiuk
Szkoła Doktorska Uniwersytetu Medycznego w Lublinie, Szkoła Doktorska Uniwersytetu Medycznego w Lublinie, ul. Witolda Chodźki 7, 20-093, Lublin, Polska
Szkoła Doktorska Uniwersytetu Medycznego w Lublinie, Szkoła Doktorska Uniwersytetu Medycznego w Lublinie, ul. Witolda Chodźki 7, 20-093, Lublin, Polska
KEYWORDS
TOPICS
ABSTRACT
Introduction and objective:
Vegetarian and vegan diets are increasingly adopted for health, environmental, and ethical reasons. These dietary patterns are rich in antioxidants, such as lutein and zeaxanthin, which may support retinal health. However, exclusion of animal-derived foods may increase the risk of deficiencies in nutrients essential for visual function, particularly vitamin B12, iron, long-chain omega-3 fatty acids, and vitamin A.
Brief description of the state of knowledge:
The aim of the review is to summerise current evidence on the relationship between vegetarian and vegan diets and visual acuity as well as overall ocular health, with emphasis on both protective mechanisms and deficiency-related risks. A narrative literature review was conducted using PubMed/PMC, Web of Science, and Scopus. English-language publications from 2001 to 2025 were screened using keywords related to plant-based diets, visual acuity, ocular diseases, and selected micronutrients.
Summary:
Higher intake of lutein and zeaxanthin is associated with increased macular pigment and may lower the risk of late age-related macular degeneration and cataract formation in some populations. In contrast, inadequately planned vegetarian or vegan diets may lead to vitamin B12 and iron deficiency, which have been linked to nutritional optic neuropathy and retinal vascular changes, as well as low EPA and DHA status that may adversely affect retinal function. Insufficient vitamin A intake may impair the visual cycle and contribute to night blindness and ocular surface disorders. Well-planned plant-based diets can support ocular health; however, careful attention to vitamin B12, iron, omega-3 fatty acids, and vitamin A intake is necessary. Regular monitoring and appropriate supplementation or fortification may help reduce the risk of preventable vision impairment.
Vegetarian and vegan diets are increasingly adopted for health, environmental, and ethical reasons. These dietary patterns are rich in antioxidants, such as lutein and zeaxanthin, which may support retinal health. However, exclusion of animal-derived foods may increase the risk of deficiencies in nutrients essential for visual function, particularly vitamin B12, iron, long-chain omega-3 fatty acids, and vitamin A.
Brief description of the state of knowledge:
The aim of the review is to summerise current evidence on the relationship between vegetarian and vegan diets and visual acuity as well as overall ocular health, with emphasis on both protective mechanisms and deficiency-related risks. A narrative literature review was conducted using PubMed/PMC, Web of Science, and Scopus. English-language publications from 2001 to 2025 were screened using keywords related to plant-based diets, visual acuity, ocular diseases, and selected micronutrients.
Summary:
Higher intake of lutein and zeaxanthin is associated with increased macular pigment and may lower the risk of late age-related macular degeneration and cataract formation in some populations. In contrast, inadequately planned vegetarian or vegan diets may lead to vitamin B12 and iron deficiency, which have been linked to nutritional optic neuropathy and retinal vascular changes, as well as low EPA and DHA status that may adversely affect retinal function. Insufficient vitamin A intake may impair the visual cycle and contribute to night blindness and ocular surface disorders. Well-planned plant-based diets can support ocular health; however, careful attention to vitamin B12, iron, omega-3 fatty acids, and vitamin A intake is necessary. Regular monitoring and appropriate supplementation or fortification may help reduce the risk of preventable vision impairment.
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