Non-insulin dependent diabetes mellitus (NIDDM) is associated with chronic hyperglycemia, which increases the risk of developing microvascular and macrovascular complications. Elevated triglyceride (TG) and VLDL cholesterol levels and low levels of HDL cholesterol have also been frequently reported in NIDDM patients. A diet high in complex carbohydrate and low in fat is typically recommended for management of NIDDM, however, this has recently been challenged by scientific reports of the benefits of dietary intakes high in monounsaturated fat. Thirty-two individuals with NIDDM were randomized to receive either Ensure with Fibre® (30% fat) or a high monounsaturated fatty acid product, Glucerna® (50% fat). These products were consumed for 28 days at 280% of daily energy intake. Post-treatment, dietary compliance was verified by a higher plasma TG 18:1 n-9 (p < 0.001)="" in="" the="" glucerna®="" group="" and="" a="" higher="" plasma="" tg="" 18:2="" n-6="" (p="">< 0.001)="" in="" the="" ensure="" with="" fibre®="" group.="" the="" postprandial="" rise="" in="" blood="" glucose="" levels,="" determined="" by="" fingerprick="" samples,="" was="" significantly="" lower="" (p="">< 0.01)="" in="" the="" glucerna®="" group.="" trends="" of="" clinical="" interest="" were="" greater="" mean="" decreases="" in="" the="" glucerna®="" group="" compared="" to="" the="" ensure="" with="" fibre®="" group="" in:="" fructosamine,="" 9.13="" umol/l="" vs="" 0.14="" umol/l;="" glucose,="" 1.61="" mmol/l="" vs="" 0.63="" mmol/l;="" and="" insulin,="" 46.0="" pmol/l="" vs="" 12.6="" pmol/l;="" respectively.="" however,="" overall,="" fasting="" plasma="" glucose,="" fructosamine,="" tg="" and="" cholesterol="" levels="" were="" not="" significantly="" different="" between="" groups.="" thus,="" in="" these="" patients,="" the="" high="" monounsaturated="" fat="" diet="" and="" the="" standard="" diet="" were="" similar="" with="" regard="" to="" usual="" indicators="" of="" carbohydrate="" and="" lipid="" metabolism.="" a="" high="" monounsaturated="" fat="" diet="" appears="" to="" pose="" no="" risk="" to="" lipoprotein="" metabolism="" in="" niddm="">