Daily supplements of soluble fiber may improve metabolic measures and slim waistlines in type-2 diabetics with the metabolic syndrome, says new data from Brazil.
Metabolic syndrome (MetS) is a condition characterized by central obesity, hypertension, and disturbed glucose and insulin metabolism. The syndrome has been linked to increased risks of both type-2 diabetes and cardiovascular diseases.
A daily 10 grams dose of the partially hydrolyzed guar gum (Benefiber; Novartis Brasil) for six weeks was associated with significant reductions in weight size and levels of HbA1c, a marker of long-term presence of excess glucose in the blood, report scientists from the Universidade Federal do Rio Grande do Sul.
“In patients with type-2 diabetes and the MetS, the addition of partially hydrolyzed guar gum to the usual diet improved the MetS profile and factors associated with cardiovascular risk,” they wrote in the British Journal of Nutrition .
“This soluble fiber consumption might be included in the dietary management of type-2 diabetic patients.”
According to the Rio-based researchers, partially hydrolyzed guar gum soluble fiber is produced from guar gum by an enzymatic process. The ingredient has the same chemical structure as native guar gum, but it a lot shorter.
The researchers recruited forty-four type 2 diabetics with an average age of 62 to participate in their randomized controlled clinical trial. Participants were randomly assigned to one of two groups: The control group, which continued to consume their usual diet, or the intervention group, which had the usual diet supplemented with an additional 10 grams per day of the partially hydrolyzed guar gum.
After six weeks of intervention, the results showed that waist circumference decreased significantly from an average of 103.5 cm to an average of 102.3 cm.
In addition, HbA1c decreased by 0.31%, while trans-fatty acid levels decreased from 71 to 57 mg/l.
“The reduction in HbA1c (0.3%) is comparable with that accepted as significant in clinical trials when a novel drug is added to conventional anti-hyperglycaemic agents,” explained the researchers.
On the other hand, the only change in the control group was a 0.9 cm reduction in weight circumference.
Commenting on the potential mechanism, the researchers noted that soluble fiber can increase the viscosity of gut contents, “reducing glucose diffusion through the unstirred water layer and the accessibility of alpha-amylase to its substrates, and decreases pancreatic enzyme activities.
“These effects can blunt the postprandial increase in glucose and insulin, resulting in HbA1c decrease.”
“The results of the present study suggest that patients with diabetes should have a dose of 10 g partially hydrolyzed guar gum added to their usual diet to improve their MetS profile,” wrote the researchers.
“From a practical, clinical perspective, patients can be encouraged to include a fiber-rich food, especially soluble fiber, in their diet.
“For example, the intake of 10 g of soluble fiber would mean a daily consumption of two tablespoons of oats (30 g), two slices of rye bread (50 g), a ladle of black beans (140 g), a slice of papaya (150 g) and an orange (180 g).”
Source: British Journal of Nutrition
Published online ahead of print, FirstView Articles, doi: 10.1017/S0007114513001025
“Improvement of the metabolic syndrome profile by soluble fibre – guar gum – in patients with type 2 diabetes: a randomised clinical trial”
Authors: V. Dall'Alba, F. Moraes Silva, J. Pecanha Antonio, T. Steemburgo, C. Persh Royer, J. Carnevale Almeida, J.L. Gross, M.J. Azevedo