Dried plums, considered a healthy food in the West and used as medicine in India, contain phenolic compounds with protective actions against age-related diseases. Effects of oral plum ekisu (concentrated juice) on lipid and glucose tolerance were assessed in insulin-resistant obese Wistar fatty rats. Plum ingestion decreased blood glucose (P < 0.05) and plasma triglyceride concentrations (P < 0.01) compared with controls. Plum treatment for 2 weeks reduced areas under the curve (AUCs) for glucose and insulin during a glucose tolerance test. In db/db mice, plum decreased these AUCs, and also blood glucose during an insulin tolerance test. Plum treatment significantly increased plasma adiponectin concentrations and PPARgamma mRNA expression in adipose tissue from Wistar fatty rats. Plum thus may increase insulin sensitivity in these rats via adiponectin-related mechanisms.