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Benefits of Vitamin A

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Evidence-Based Benefits

  • Vision — vitamin A is a component of rhodopsin, the photoreceptor pigment in retinal rod cells; deficiency causes night blindness and, if severe, xerophthalmia and irreversible corneal damage
  • Immune function — vitamin A maintains epithelial barriers (skin, gut lining, respiratory tract) and supports differentiation and function of T cells, B cells, and natural killer cells; a 2009 Lancet meta-analysis found supplementation in deficient children reduced all-cause mortality by 24%
  • Skin health — retinoids regulate keratinocyte proliferation and differentiation; prescription retinoids are first-line treatments for acne and photoaging, while dietary vitamin A supports skin integrity
  • Reproductive health — vitamin A is required for spermatogenesis, oocyte development, and embryonic development; deficiency is associated with infertility and birth defects

What the Research Says

Vitamin A's essential role in human health is supported by decades of research. A landmark Lancet meta-analysis by Imdad et al. (2010) of 43 trials (n=215,633 children) found that vitamin A supplementation reduced all-cause mortality by 24% and diarrhea-related mortality by 28% in deficient populations. The AREDS2 trial (2013) demonstrated that a formulation including beta-carotene alternatives (lutein/zeaxanthin) slowed progression of age-related macular degeneration. However, the ATBC and CARET trials showed that high-dose beta-carotene supplementation increased lung cancer risk in smokers by 18-28%, leading to recommendations against supplementation in this population.

Related Conditions

Immune FunctionEye HealthSkin Health
Full Vitamin A Guide

References

  1. (). Vitamin A supplementation for preventing morbidity and mortality in children from 6 months to 5 years of age. Cochrane Database of Systematic Reviews. DOI
  2. (). Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: the AREDS2 randomized clinical trial. JAMA. DOI
  3. (). The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. New England Journal of Medicine. DOI