Effects of diets with high carbohydrate content on diabetic hyperlipidaemia and microalbuminuria

Recent dietary recommendations for patients with diabetes mellitus have focussed on the liberalisation of carbohydrate intake to at least 50% of total calories. However, there are reports that this diet may cause adverse metabolic effects as a result of high intake of carbohydrate. Whether this high-carbohydrate diet will exacerbate hypertriglyceridaemia, which increases the risk of atherosclerosis, and diabetic microalbuminuria, which predisposes to progressive renal failure, is unknown. The dietary intake of 28 patients with insulin-dependent diabetes mellitus was assessed by diet histories with both questionnaire surveys and 3-day recall methods. The dietary contents of different constituents were graded according to the type and amount of food typically eaten, and the frequency of their consumption in the past 6 months. Twelve patients were found to have a high dietary intake of carbohydrate and this was confirmed by detailed assessment of food intake records over a 3-day period. The carbohydrate intake of these 12 patients amounted to at least 55% of total calories. Total calorie intake, body weight, mean blood pressure, glycaemic control, and glomerular filtration rate were similar between the 12 patients with high intake of carbohydrate and the other 16 patients with low intake. Urinary protein and albumin appearance as measured by dye binding and immunoassay, fasting cholesterol, triglyceride and high-density lipoprotein cholesterol were also comparable between the two groups. This study provides evidence that a high-carbohydrate diet in the treatment of diabetes mellitus is not associated with significant alterations in the amount of microalbuminuria or in hypertriglyceridaemia.