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Updated: Sep 30, 2026

Formulation of Vitamin A Tracer Doses for Administration to Human Subjects using Retinol Isotope Dilution Technique
Published on: March 31, 2026
Vitamin A deficiency in Nigeria
1International Centre for Eye Health, Institute of Ophthalmology, University College, London.
Abstract:
Childhood blindness is second only to cataract in magnitude of world blindness when the "blind years" is considered. The "blind years" is the number of years a person lives with blindness. Studies have shown that over 34%-69% of childhood blindness in Nigeria is caused by corneal opacity, which results mainly from an interplay of vitamin A deficiency, measles and harmful traditional eye practices. However, vitamin A deficiency which manifests in the eye as xerophthalmia is the dominant problem in these children. The purpose of this review is to stress the importance of xerophthalmia, which is of public health significance, as an important cause of childhood blindness in Nigeria. Studies involving surveys of xerophthalmia, childhood and nutritional blindness are reviewed with data extracted from a nationwide survey on prevalence of xerophthalmia. The likely explanation for vitamin A deficiency in Nigerian children is discussed with possible solutions and recommendations made to control this avoidable and devastating cause of blindness.
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