AIM: To examine the effect of cranberry ingestion on lipid profiles in Type 2 diabetic patients taking oral glucose-lowering drugs.

METHODS: Thirty Type 2 diabetic subjects (16 males and 14 females; mean age 65 +/- 1 years) who were taking oral glucose-lowering medication regularly were enrolled in this randomized, placebo-controlled, double-blind study. Changes in lipid profiles, oxidized low-density lipoprotein (ox-LDL), glycaemic control, components of the metabolic syndrome, C-reactive protein (CRP) and urinary albumin excretion (UAE) were assessed after cranberry or placebo treatment for 12 weeks.

RESULTS: Low-density lipoprotein (LDL) cholesterol decreased significantly in the cranberry group (from 3.3 +/- 0.2 to 2.9 +/- 0.2 mmol/l, P = 0.005) and the decrease was significantly greater than that in the placebo group (-0.4 +/- 0.1 vs. 0.2 +/- 0.1 mmol/l, P 0.001). Total cholesterol and total : high-density lipoprotein (HDL) cholesterol ratio also decreased significantly (P = 0.020 and 0.044, respectively) in the cranberry group and the reductions were significantly different from those in the placebo group (P 0.001 and P = 0.032, respectively). However, ox-LDL levels did not change significantly in response to cranberry consumption. Neither fasting glucose nor glycated haemoglobin improved in either group. Changes in components of the metabolic syndrome, UAE and CRP were not significantly different between groups.

CONCLUSIONS: Cranberry supplements are effective in reducing atherosclerotic cholesterol profiles, including LDL cholesterol and total cholesterol levels, as well as total : HDL cholesterol ratio, and have a neutral effect on glycaemic control in Type 2 diabetic subjects taking oral glucose-lowering agents.