Weight loss not fiber intake tied to better blood sugar control in diabetes
Italy: Calorie restriction followed by weight loss is more useful in controlling blood sugar levels in patients with type 2 diabetes (T2D), rather than increased fiber intake, a recent study has revealed. The findings of the study were presented at the American Diabetes Association (ADA) 80th Scientific Sessions by Flavia Tramontana, a Ph.D. student at Campus Bio-Medico University of Rome, Italy. The study was subsequently published in the ADA journal Diabetes.
The short study involving overweight T2D patients showed that consumption of fewer calories resulting in a weight loss of about 2 kgs led to better blood sugar control than ingesting more fiber.
The efficacy of increased intake of dietary fiber to improve blood sugar levels in diabetes patients is still controversial. To throw light on the same, Tramontana and colleagues tested the effect of high-fiber diet and fiber supplements on glycemic control in patients with T2D on metformin monotherapy in this randomized open-label comparator-controlled study.
The study included 78 T2D overweight patients on metformin monotherapy. They were randomized in the ratio 1:2:1 to 12 weeks intensive nutrition program to follow a high-fiber diet (HFD), dietary fiber supplementation (FS) or standard diet recommendations (SDR). In all the groups, dietary recommendations were reinforced every 4 weeks by study dieticians. Biochemistry, anthropometric measures, food frequency questionnaires to assess DFI were collected at baseline and after 12 weeks.
Key findings of the study include:
- At baseline groups did not differ in terms of mean age, BMI, metformin intake, HbA1c, fiber and calorie intake.
- After three months, DFI significantly increase in both HDF and FS group but not in SDR group (HFD: 19.8 ± 6.1 g vs. 24.3 ± 6.8 g; FS: 17.5 ± 5.9 g vs. 27.0 ± 6.2 g; SDR: 22.8 ± 9.1 g vs. 21.2 ± 6.4 g). HbA1c significantly improved in all groups (HFD: 7.1 ± 0.5 % vs. 6.6 ± 0.6 %; FS: 7.1 ± 0.5 % vs. 6.8 ± 0.5 %; SDR: 7.2 ± 0.4 % vs. 6.7 ± 0.5 g).
- All HFD, FS and SDR intervention reduced mean body weight by 2.1 ± 2.6 Kg, 1.0 ± 1.8 Kg and 1.1 ± 2.1 Kg, respectively.
- Changes in HbA1c and body weight did not differ among groups.
- A significant correlation between calorie intake and the reduction of HbA1c levels was seen across groups.
- No significant correlation between DFI and HbA1c levels was observed.
"Intensive nutrition education programs with monthly meetings similarly reduced HbA1c in all groups. Furthermore, our study suggested that rather than fiber intake, caloric restriction followed by moderate weight loss is the main driver for glycemic improvement in overweight patients with T2D," concluded the authors.
Consuming fewer calories resulting in weight loss of around 2 kg was associated with better blood sugar control than ingesting more fiber.These findings should not be interpreted to mean that patients should stop trying to incorporate more fiber into their diet, the authors caution.
The study, "The Effect of Dietary Fiber in Combination with Metformin Therapy in Type 2 Diabetes," is published in the journal Diabetes.