A systematic review and meta-analysis of the association between vitamin A intake, serum vitamin A, and risk of liver cancer

Nutr Health. 2018 Jun;24(2):121-131. doi: 10.1177/0260106018777170. Epub 2018 May 23.


Background: Previous evidence supports that vitamin A decreases the risk of several types of cancer. However, the association between vitamin A and liver cancer is inconclusive.

Aim: This systematic review and meta-analysis summarizes the existing literature, discussing the association between vitamin A intake, serum vitamin A, and liver cancer in adult populations.

Methods: A systematic literature review was performed by searching the EMBASE, PubMed, Scopus and International Pharmaceutical Abstract databases using terms related to vitamin A (e.g. retinol, α-carotene, β-carotene, and β-cryptoxanthin) and hepatic cancer without applying any time restriction. A meta-analysis was performed using random effect models.

Results: The meta-analysis of five studies showed no association between serum retinol and liver cancer (pooled risk ratio = 1.90 (0.40-9.02); n = 5 studies, I2 = 92%). In addition, the systematic review of studies from 1955 to July 2017 found studies that indicated no association between the intake and serum level of α-carotene ( n = 2) and β-cryptoxanthin ( n = 1) and the risk of liver cancer. Further, the associations between retinol intake ( n = 3), β-carotene intake ( n = 3), or serum β-carotene ( n = 3) and liver cancer were inconclusive.

Conclusions: Current information on the association between vitamin A intake and liver cancer or serum vitamin A and liver cancer are limited. Most studies demonstrated no association between dietary vitamin A and the risk of liver cancer. However, the finding was based on a small number of studies with potential publication bias. Therefore, large observational studies should be conducted to confirm these associations.

Keywords: Vitamin a; beta carotene; carotenoids; liver cancer; liver neoplasms; retinol.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Beta-Cryptoxanthin / administration & dosage
  • Beta-Cryptoxanthin / blood
  • Carotenoids / administration & dosage
  • Carotenoids / blood
  • Humans
  • Liver Neoplasms / blood*
  • Liver Neoplasms / epidemiology*
  • Observational Studies as Topic
  • Randomized Controlled Trials as Topic
  • Risk Factors
  • Vitamin A / administration & dosage*
  • Vitamin A / blood*
  • beta Carotene / administration & dosage
  • beta Carotene / blood


  • Beta-Cryptoxanthin
  • beta Carotene
  • Vitamin A
  • Carotenoids
  • alpha-carotene