Effects of short-term high dose intake of evening primrose oil on plasma and cellular fatty acid compositions, α-tocopherol levels, and erythropoiesis in normal and Type 1 (insulin-dependent) diabetic men

In addition to their usual diet, nine Type 1 (insulin-dependent) diabetic men and ten male control subjects took 20 g d, alpha-tocopheryl acetate enriched evening primrose oil (14.45 g 18:2c,omega 6, 1.73 g 18:3c,omega 6, 400 mg d,alpha-tocopheryl acetate) daily for one week. At start, diabetic patients had more 14:0, 15:0 and 18:2c,omega 6, and less 16:0, 16:1c,omega 7, 18:1c,omega 7, 18:3c,omega 6, 20:3c,omega 9, 20:3c,omega 6, 20:4c,omega 6 and 22:6c,omega 3 in plasma, erythrocytes and/or platelets. Furthermore, they had lower 16:1c,omega 7/16:0, 18:1c,omega 7/16:0, and 20:4c,omega 6/20:3c,omega 6 ratios and a higher 20:3c,omega 6/18:3c,omega 6 ratio. In diabetic patients, alpha-tocopherol levels in erythrocytes were lower, whereas those in plasma were normal. In both groups, oil intake changed fatty acid profiles. Most markedly, 20:3c,omega 6 increased, whereas the ratios 20:3c,omega 6/18:3c,omega 6 and 20:4c,omega 6/20:3c,omega 6 decreased. 20:4c,omega 6 increased in control subjects, but not in diabetic patients. Erythrocytes and platelets responded differently in their fatty acid profiles. alpha-tocopherol rose in plasma and, although less for diabetic patients, in erythrocytes. In diabetic patients as well as in control subjects, erythrocyte count, haemoglobin level, mean corpuscular haemoglobin content and concentration increased and glycosylated haemoglobin percentage decreased without an apparent decline in blood glucose levels. Plasma beta-thromboglobulin and platelet factor 4 decreased, especially in diabetic patients.