Favourable effects of the Dietary Approaches to Stop Hypertension diet on glucose tolerance and lipid profiles in gestational diabetes: a randomised clinical trial

British Journal of Nutrition

Nov 2012

DOI: 10.1017/S0007114512004242

Citations:188

Influential Citations:11

Interventional (Human) Studies

Enhanced Details

Methods

Two-arm parallel randomized controlled clinical trial conducted in Kashan, Iran (April–December 2011). Pregnant women aged 18–40 years diagnosed with gestational diabetes by a 100 g OGTT at 24–28 weeks' gestation were randomized to control diet or DASH diet for 4 weeks (n=17 per group; 34 completed). Diets had similar macronutrient distributions; the DASH diet was richer in fruits, vegetables, whole grains and low-fat dairy and lower in saturated fats, cholesterol and refined grains. Compliance monitored via weekly interviews and 3-day dietary records; no lipid-lowering medications used; ethics approval obtained and written consent secured.

Intervention

DASH eating pattern for 4 weeks; macronutrient distribution similar to control; diet enriched in fruits, vegetables, whole grains and low-fat dairy; lower in saturated fats, cholesterol and refined grains; daily sodium intake around 2400 mg; delivered via a 7-day menu cycle; compliance monitored with weekly interviews and 3-day dietary records.

Results

DASH diet for 4 weeks improved glucose tolerance and lipid profiles vs control. Glucose after an oral glucose load was lower at 60, 120, and 180 minutes (P=0.02, 0.001, 0.002). HbA1c decreased (P=0.001). Total cholesterol, LDL-cholesterol and triglycerides fell, and total:HDL ratio improved (P=0.01, 0.005, 0.01, 0.008). Systolic blood pressure decreased more with DASH (P=0.001). Fasting glucose change was not significant (P=0.09). Birth outcomes favored DASH: lower birth weight (approx. 3083 g vs 3641 g; P=0.006) and lower cesarean rate (41.2% vs 88.2%; P=0.001). Insulin therapy after delivery was less needed (11.8% vs 58.8%; P=0.005). Authors conclude that the DASH eating pattern for 4 weeks improves glucose tolerance, lipid profiles, and certain pregnancy outcomes in women with gestational diabetes.

Limitations

Short duration (4 weeks); small sample size (n=34 analyzed); potential bias related to dietistr delivering both diets and concerns about generalizability to other populations.

Abstract

Although gestational diabetes mellitus (GDM) is associated with an increased risk of maternal and neonatal morbidity, there is no consensus as to the optimal approach of nutritional management in these patients. The present study was designed to assess the effect of the Dietary Approaches to Stop Hypertension (DASH) eating plan on glucose tolerance and lipid profiles of pregnant women with GDM. The present randomised controlled clinical trial was performed among thirty-four women diagnosed with GDM at 24–28 weeks of gestation. Subjects were randomly assigned to consume either the control diet (n 17) or the DASH eating pattern (n 17) for 4 weeks. The control diet was designed to contain 45–55 % carbohydrates, 15–20 % protein and 25–30 % total fat. The macronutrient composition of the DASH diet was similar to the control diet; however, the DASH diet was rich in fruits, vegetables, whole grains and low-fat dairy products, and contained lower amounts of saturated fats, cholesterol and refined grains with a total of 2400 mg Na/d. Fasting blood samples were taken at baseline and after 4 weeks of intervention to measure fasting plasma glucose, glycated Hb (HbA1c) and lipid profiles. Participants underwent a 3 h oral glucose tolerance tests and blood samples were collected at 60, 120 and 180 min to measure plasma glucose levels. Adherence to the DASH eating pattern, compared with the control diet, resulted in improved glucose tolerance such that plasma glucose levels reduced at 60 ( − 1·86 v. − 0·45 mmol/l, Pgroup= 0·02), 120 ( − 2·3 v. 0·2 mmol/l, Pgroup= 0·001) and 180 min ( − 1·7 v. 0·22 mmol/l, Pgroup= 0·002) after the glucose load. Decreased HbA1c levels ( − 0·2 v. 0·05 %, Pgroup= 0·001) was also seen in the DASH group compared with the control group. Mean changes for serum total ( − 0·42 v. 0·31 mmol/l, Pgroup= 0·01) and LDL-cholesterol ( − 0·47 v. 0·22 mmol/l, Pgroup= 0·005), TAG ( − 0·17 v. 0·34 mmol/l, Pgroup= 0·01) and total:HDL-cholesterol ratio ( − 0·6 (sd 0·9) v. 0·3 (sd 0·8), Pgroup= 0·008) were significantly different between the two diets. Additionally, consumption of the DASH diet favourably influenced systolic blood pressure ( − 2·6 v. 1·7 mmHg, Pgroup= 0·001). Mean changes of fasting plasma glucose ( − 0·29 v. 0·15 mmol/l, Pgroup= 0·09) were non-significant comparing the DASH diet with the control diet. In conclusion, consumption of the DASH eating pattern for 4 weeks among pregnant women with GDM resulted in beneﬁcial effects on glucose tolerance and lipid profiles compared with the control diet. show less