Yu E, et al. - Researchers utilized a case-cohort design nested within the PREDIMED trial to evaluate the connections between arginine-based metabolites and incident type 2 diabetes (T2D). They observed that positive changes of citrulline and ornithine, and negative changes in symmetric dimethylarginine [SDMA] and arginine/(ornithine+citrulline) were related to concurrent 1-year changes in HOMA-IR. As compared to individuals in Mediterranean diet groups, individuals in the low fat diet group experienced a higher risk of T2D for 1-year changes in N-monomethyl-l-arginine [NMMA]. The findings from the present study suggested that arginine bioavailability is important in T2D pathophysiology.