Different data have been reported with respect to the distribution of plasma and tissue fatty acids in patients with diabetes mellitus and some studies have suggested that severe diabetes is required to produce the fatty acid abnormalities observed in the diabetic rat. We studied the plasma fatty acid profile with particular attention to the omega 3 and 6 fatty acids in 14 non insulin dependent (NIDDM) diabetic Melanesians, majority of whom were poorly controlled (mean glycosylated haemoglobin levels of 12.8%), their mean age was 43.0 +/- 6.3 with disease duration of 5.2 +/- 4.8 years. Plasma fatty acids were estimated by gas chromatography (GC) using a flame ionisation detector (FID). Each diabetic was age and sex matched with a non diabetic, healthy control. Though the plasma concentrations of arachidonic (20:4, omega-6), eicosapentanoic (20:5 omega-3) and docosahaxaenoic (22:6 omega-3) acids were lower than in control subjects, these values were of no significant difference. Similarly, no significant differences were observed between the total plasma saturated fatty acids (palmitic and stearic acids) of diabetic and control subjects. The results of this pilot study suggest that poor metabolic control may not be associated with plasma fatty acid abnormalities in NIDDM patients.