Catalyzes the saturation of all-trans-retinol to all-trans-13,14-dihydroretinol. Does not exhibit any activity toward all-trans-retinoic acid, nor 9-cis, 11-cis or 13-cis-retinol isomers. May play a role in the metabolism of vitamin A. Independently of retinol conversion, may regulate liver metabolism upstream of MLXIPL/ChREBP. May play a role in adipocyte differentiation. A + all-trans-13,14-dihydroretinol = AH2 + all-trans-retinol Expressed in liver; expression positively correlates with obesity and liver steatosis (PubMed:28855500). Expressed in adipose tissue; expression tends to be decreased in obese versus lean individuals (PubMed:19139408). Belongs to the carotenoid/retinoid oxidoreductase family. CrtISO subfamily. Truncated N-terminus. Truncated N-terminus.