Effects of Glucomannan Noodle on Diabetes Risk Factors in Patients with Metabolic Syndrome: A Double-Blinded, Randomized Crossover Controlled Trial

Glucomannan is a water-soluble dietary fiber derived from the root of Amorphophallus konjac that can improve blood sugar, blood fat concentration, and weight management, and has other health benefits. The aim of this study is to investigate the effect of glucomannan noodles on components of the metabolic syndrome. A randomized, double-blind, placebo-controlled, crossover study, 32 individuals with metabolic syndrome were received a daily servings of 400 gram glucomannan noodles for a period of four weeks. After two weeks of wash out period, they received a placebo noodles for four weeks. There were no statistical difference in calories, carbohydrate, protein, fat and dietary fiber intake from 24 h food recalls between glucomannan noodles and placebo noodles groups. However, the body weight, body mass index, and waist circumference had significantly decreased after 4-week intervention in both groups, but high sensitivity C-reactive protein was lowered only in glucomannan noodles group. Moreover, the 24 individuals with type 2 diabetes had significantly decreased body weight, BMI, waist circumference, hs-CRP, and glycated hemoglobin after glucomannan noodles intervention. The rest of lipid profile, fasting blood glucose, insulin, and HOMA-IR of the subjects did not show any significant difference. This study showed that glucomannan noodles as a staple food can contribute to metabolic syndrome in adults predisposed to type 2 diabetes.