Indeed, increasing amounts of Lactobacillus in the gut microbiota may contribute to attenuate liver disease via increased short-chain fatty acids (SCFA)30 and, in particular, via production of D-Lactate by bacteria,31 which is hydrolyzed in mammal cells by the mitochondrial D-lactate dehydrogenase (D-Ldh).32 This SCFA is an important energy substrate for liver mitochondria33 and may inhibit macrophage pro-inflammatory response.34 Although D-lactate was not detectable in serum or liver tissue, supplementation with L. reuteri induced a fourfold increase of hepatic D-Ldh mRNA. Here, DLD is linked to liver disorder.