1. Two groups of patients with non-insulin-dependent diabetes mellitus (NIDDM), with dietary advice randomized between a low-carbohydrate (LC) diet and a modified-fat (MF) diet, were followed to determine the effect of diet on phospholipid fatty acid composition of platelets and on development of retinopathy in the 7 years following diagnosis. There was a tendency for retinopathy to occur more frequently in those randomiEd to the LC diet. This difference was not statistically significant, and fatty acid composition of platelets did not differ significantly in those with and without retinopathy.
2. Linoleic acid values from platelet phospholipid fatty acids were significantly higher in NIDDM on an MF diet compared with an LC diet.
3. There was no difference between the two dietary subgroups with respect to platelet arachidonic acid, but this was lower in the whole diabetic population when compared with non-diabetics.
4. The arachidonic acid values correlated with neither glycosylated haemoglobin nor mean glycaemia.
5. Significant correlation between the fatty acid values for platelets and plasma cholesterol esters was found only for 16:0.