Effect of High Versus Low Carbohydrate Intake in the Morning on Glycemic Variability and Glycemic Control Measured by Continuous Blood Glucose Monitoring in Women with Gestational Diabetes Mellitus—A Randomized Crossover Study

Abstract

Carbohydrate is the macronutrient that has the greatest impact on blood glucose response. Limited data are available on how carbohydrate distribution throughout the day affects blood glucose in women with gestational diabetes mellitus (GDM). We aimed to assess how a high-carbohydrate morning-intake (HCM) versus a low-carbohydrate-morning-intake (LCM), affect glycemic variability and glucose control. In this randomized crossover study continuous glucose monitoring (CGM) was performed in 12 women with diet treated GDM (75 g, 2-h OGTT ≥ 8.5 mmol/L), who went through 2 × 3 days of HCM and LCM. A within-subject-analysis showed a significantly higher mean amplitude of glucose excursions (MAGE) (0.7 mmol/L, p = 0.004) and coefficient of variation (CV) (5.1%, p = 0.01) when comparing HCM with LCM, whereas a significantly lower mean glucose (MG) (−0.3 mmol/L, p = 0.002) and fasting blood glucose (FBG) were found (−0.4 mmol/L, p = 0.01) on the HCM diet compared to the LCM diet. In addition, insulin resistance, expressed as Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), decreased significantly during HCM. Results indicate that a carbohydrate distribution of 50% in the morning favors lower blood glucose and improvement in insulin sensitivity in women with GDM, but in contrary gives a higher glycemic variability.

<p>A Review of Research Progress on Glycemic Variability and Gestational Diabetes</p>

“…Carreiro et al 52 found that receiving dietary consultation can improve the GV of pregnant women with GDM. A study by Rasmussen et al 53 showed that the GV of pregnant women with GDM in the group eating a high-carbon breakfast was significantly higher than that of pregnant women with GDM in the group eating a low-carbon breakfast. Similarly, a small sample study 54 showed that the low-glycemic-load diet significantly reduced the GV index of pregnant women with GDM compared with the high-glycemic-load diet.…”

“…50,51 Three studies have shown specifically that dietary control can reduce blood glucose fluctuations in pregnant women with GDM. [52][53][54] Studies also have shown that reducing postprandial hyperglycemia can effectively reduce postprandial hyperglycemia peak. Carreiro et al 52 found that receiving dietary consultation can improve the GV of pregnant women with GDM.…”

Diet and Healthy Lifestyle in the Management of Gestational Diabetes Mellitus

“…In the same study, insulin resistance (as measured by homeostatic model assessment for insulin resistance (HOMA-IR)) significantly decreased during the period with the high carbohydrate intake in the morning. However, Rasmussen et al also found a higher mean amplitude of glucose excursions and coefficient of variation in the group receiving a high carbohydrate intake in the morning as compared with the low intake [ 31 ]. There is a lack of randomized clinical trials studying whether a high or low carbohydrate intake in the morning is preferential.…”

Glycemic Variability and CNS Inflammation: Reviewing the Connection

“…While total calories per day were equal between the groups, omission of breakfast was associated with higher postprandial glucose responses after lunch and dinner, which may be mediated by lower glucagon-like peptide 1 and insulin secretion [ 125 ]. Finally, in a within-subject analysis study of women with gestational diabetes mellitus, high carbohydrate morning meals also had higher measures of MAGE but lower mean glucose compared to equicaloric diets that distributed carbohydrates throughout the day [ 126 ].…”