Nutritional Risk of High-Carbohydrate, Guar Gum Dietary Supplementation in Non-Insulin-Dependent Diabetes Mellitus

Dietary supplementation with high-carbohydrate, guar gum fiber (HCF) is effective in acutely blunting postprandial blood glucose levels. We report the effect of such supplementation on the diet and nutritional status of a group of 16 subjects with non-insulin-dependent diabetes mellitus (NIDDM) who incorporated either HCF bars (35.7 g carbohydrate and 6.6 g guar gum/bar) or placebo bars (identical except for the absence of guar gum) into the diet for 6 mo as part of a double-blind, randomized clinical trial. The HCF subjects achieved mean daily intake of 4.8 ± 0.4 bars, constituting 51.2 ± 3.1% of total calories and providing 29.7 ± 2.6 g guar gum daily. Energy intakes and body weight did not change significantly in either group. Food consumption patterns and nutrient intakes did change, although not enough to impair the nutritional integrity of the diet because the bars themselves served as a source of nutrients. The bars were rich in thiamin, B₆, folacin, phosphorus, iron, zinc, and copper, adequately replacing any decrease in nutrient intake as a result of foods being dropped from the diet. In fact, daily intakes of B₆, folacin, and copper actually increased due to contributions from the bars. Nutrients in which the bars were poor (vitamins A, C and B₁₂) resulted in suboptimal intakes (<66% RDA). Although no significant change in nutritional status of the HCF group occurred as determined by arm muscle area, arm fat area, hemoglobin, hematocrit, or serum albumin, transferrin, iron, ferritin, calcium, phosphate, B₁₂, and magnesium levels, these indicators of nutritional status are rather insensitive. To ensure adequate nutrient intake and thus nutritional status with HCF diets, vitamin and mineral supplementation is probably advisable over the long term.