The Effect of Red Palm Oil on Vitamin A Deficiency: A Meta-Analysis of Randomized Controlled Trials

Red palm oil (RPO) has been investigated for preventing or alleviating vitamin A deficiency (VAD). Previous data has offered inconclusive and inconsistent results about the effects of RPO in patients with VAD. Our objective was to undertake a meta-analysis to assess the effects of RPO in preventing VAD in the population. After conducting a comprehensive literature search, nine randomized controlled trials (RCTs) were included. Overall, when trial results were pooled, the results indicated that RPO reduced the risk of VAD (relative risk (RR) (95% confidence interval (CI)) = 0.55 (0.37, 0.82), p = 0.003), increasedserum retinol levels in both children (p < 0.00001) and adults (p = 0.002), and increased β-carotene levels (p = 0.01). However, RPO supplementation did not have a significant overall effect on serum α-carotene levels (p = 0.06), body weight (p = 0.45), and haemoglobin levels (p = 0.72). The results also showed that low level of PRO intake (≤8 g RPO) could increase serum retinol concentrations whereas PRO intake above 8 g did not lead to further increase of serum retinol concentrations. This meta-analysis demonstrated that RPO might be effective for preventing or alleviating VAD.