Short-term effect of plant-based Nordic diet versus carbohydrate-restricted diet on glucose levels in gestational diabetes - the eMOM pilot study

BACKGROUND

The optimal nutritional treatment for gestational diabetes (GDM) is still a matter of debate. With increasing rates of GDM and potential negative consequences for the health of mother and child, the best treatment should be established. The Nordic diet with emphasis on plant-based protein show promising health outcomes in other populations but has yet to be investigated in GDM population. The aim of this study, which is part of the "Effect of plant-based Nordic diet versus carbohydrate-restricted diet on glucose levels in gestational diabetes" (eMOM) pilot study was to compare the short-term effects of healthy Nordic diet (HND) and the currently recommended moderate restriction of carbohydrates diet (MCRD) on glucose and lipid metabolism in women with GDM.

METHODS

This was a randomized crossover where each of the diet interventions (HND and MCRD) were consumed for 3 days with a 3-day wash-out period in between. In total, 42 pregnant women diagnosed with GDM (< 29 + 0 gestational week) were randomized. Glucose data was collected by continuous glucose monitors (CGM, Freestyle Libre®, Abbott, USA) worn for 14 days, and participants gave blood samples before and after diet interventions. The primary outcome was time spent in glucose target range (TIR, < 7.8 mmol/L). TIR, 3-day mean tissue glucose as well as changes in fasting glucose, homeostatic model of insulin resistance (HOMA-IR) and blood lipids were analyzed with paired samples statistical analyses.

RESULTS

Thirty-six women with complete 14 days CGM data were analyzed. Both diet interventions produced a high degree of TIR (99% SD 1.8), without a difference between the diets (p = 0.727). The 3-day mean glucose was significantly lower in HND than in MCRD (p = 0,049). Fasting insulin (p = 0,034), insulin resistance (p = 0,030), total and LDL cholesterol (p = 0,023 and 0,008) reduced more in the MCRD diet than the HND. NS differences in any other measure of CGM or blood tests.

CONCLUSIONS

HND and MCRD did not differ in terms of their short-term effect on TIR. A larger study with sufficient power is needed to confirm the differences in short-term mean glucose, insulin resistance and lipid metabolism.

TRIAL REGISTRATION

Registered in clinicaltrials.gov (21/09/2018, NCT03681054).

Association of modified Nordic diet with cardiovascular risk factors among type 2 diabetes patients: a cross-sectional study

Introduction: Cardiovascular disease (CVD) is one of the most important causes of mortality. Healthy diets can decrease CVDs and other chronic diseases especially in patients with type 2 diabetes. In this study, we investigate association between adherence to the modified Nordic diet and cardiovascular risk factors among patients with type 2 diabetes.

Methods: This cross-sectional study was conducted among 339 type 2 diabetic patients. Anthropometric indices, blood pressure, and biochemical tests were evaluated. A validated and reliable semi-quantitative food frequency questionnaire (FFQ) was used to assess dietary intake. Nordic diet scores were calculated based on median intakes of six food groups.

Results: Body mass index (BMI) was higher among participants who were in the lowest tertile of adherence to the Nordic diet (P=0.006). There was a significant association between socioeconomic status (SES) and adherence to the Nordic diet (P<0.0001). Participants who were in the top category of adherence to the diet had significantly lower levels of aspartate aminotransferase (AST) (P<0.0001). There was a significant inverse association between adherence to the Nordic diet and low density lipoprotein (LDL) levels (odds ratio [OR]=0.29 95% CI: 0.09, 0.91, P=0.025), high systolic blood pressure (SBP) levels (OR=0.35 95% CI=0.17-0.74, P=0.015), and risk of obesity (OR=0.25 95% CI: 0.10, 0.63, P=0.03).

Conclusion: Results suggest that adherence to the Nordic diet is associated with reductions in the prevalence of obesity, LDL levels and blood pressure among type 2 diabetic patients. However, additional studies are needed to confirm these findings.