A low glycemic index staple diet reduces postprandial glucose values in Asian women with gestational diabetes mellitus

Maternal and fetal outcomes in gestational diabetes mellitus: a narrative review of dietary interventions

Introduction

Gestational diabetes mellitus (GDM) is associated with a myriad of maternal and fetal complications that severely compromise the mother and child's future health. Dietary interventions are effective in reducing the risk of GDM. However, when diagnosed with GDM in 2nd and 3rd the effectiveness of these interventions on maternal and fetal health remains unexplored. Therefore, this review critically examines existing literature for short- and long-term maternal and fetal outcomes of dietary interventions followed after GDM diagnosis.

Methodology

An extensive literature search through Scopus, PubMed, and Web of Science was conducted to include original, full-text articles published in English between 2013 and April 2024. All randomized controlled trials, case-control, prospective cohort studies, and longitudinal follow-up trials that recruited GDM mothers following dietary interventions upon diagnosis were included. However, pre-pregnancy interventional, retrospective, and prospective studies reporting maternal and fetal outcomes in healthy pregnant women were excluded. This review followed the Narrative Review Checklist by the Academy of Nutrition & Dietetics, Elsevier.

Results

We reviewed the effects of eight popular dietary interventions on various short and long-term materno-fetal outcomes in women recently diagnosed with GDM. Dietary interventions such as Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and low-GI positively affected both short and long-term maternal and fetal outcomes. In contrast, fasting during Ramadan negatively affected maternal and fetal outcomes. Studies with low-carb, high-protein, and calorie restriction reported mixed findings for materno-fetal outcomes. Although certain dietary interventions have shown beneficial effects in the past literature, their findings were limited by small sample size, short intervention duration, and inconsistencies in the outcomes and population studied, compromising the quality of evidence. Further, we observed a scarcity of studies exploring the effect of dietary interventions followed during 2nd and 3rd trimesters after being diagnosed with GDM on long-term materno-fetal outcomes.

Conclusion

Dietary interventions followed during 2nd and 3rd trimesters after the diagnosis of GDM may be crucial for preventing short and long-term materno-fetal complications; however, there is a lack of strong evidence to support this notion. Future studies are recommended to monitor the long-term materno-fetal outcomes of GDM.

Postnatal glycaemic outcomes in women with high-risk gestational diabetes: Identifying key predictors for early intervention

AIMS

Women with gestational diabetes (GDM) have increased lifetime risk of developing diabetes. We aim to determine the factors contributing to poor adherence of the postpartum oral glucose tolerance test (OGTT) and identify key predictors to postpartum dysglycaemia in our Asian cohort.

METHODS

We conducted a retrospective cohort study of women with high-risk GDM (n = 561). High-risk women with GDM were defined as (1) women with diabetic-range glucose excursions on an antepartum OGTT, (2) women diagnosed GDM on early OGTT and (3) women requiring ≥20 units of insulin during antepartum period. We use logistic regression predictive models to associate maternal variables with postpartum OGTT attendance and glucose tolerance status postnatally.

RESULTS

Between March 2020 to March 2024, 58.7% (n = 329) of women returned for postpartum OGTT. Predictors for attendance of postpartum OGTT were Chinese ethnicity (odds ratio [OR] 2.11, 95% confidence interval [CI] [1.14-3.89]), pre-pregnancy body mass index (BMI) (OR 0.95 [95% CI 0.90-0.99]), first GDM (OR 2.34 [95% CI 1.39-3.96]) and 2-h glucose threshold on antepartum OGTT (OR 0.87 [95% CI 0.76-0.99]). Ethnicity influences postnatal dysglycaemia outcomes in our cohort. Chinese women, compared to women of Malay ethnicity, had a 4.5-odds of persistent postpartum dysglycaemia. An antenatal HbA1c of ≥5.7% and an elevated 2-h post-OGTT glucose value significantly predict postpartum dysglycaemia independent of ethnicity.

CONCLUSION

Ethnicity-specific prediction models integrating antepartum OGTT and HbA1c predict postpartum dysglycaemia in a multiethnic Southeast Asian cohort. Using these predictive models, we could identify high-risk patients for early intervention.

Effect of Millets Once a Day on Glycaemic Control among Women with Gestational Diabetes Mellitus in a Tertiary Care Setting - A Randomized Controlled Trial

INTRODUCTION

Gestational diabetes mellitus (GDM) affects 14% of pregnancies globally, with a prevalence of 9-16% in India. Low-glycaemic index (GI) foods like millets may help control glycaemia in GDM. This study compared glycaemic control between GDM patients consuming millets once a day (MOD) and those receiving enhanced medical nutrition therapy (MNT) for 1 month.

METHODS

A parallel-arm randomized controlled trial was conducted among 224 GDM mothers at a tertiary centre from April 2022 to December 2023. Participants were randomized into two groups: The Enhanced MNT group received standard care with education materials, while the MOD group received 200 g of millets daily for 1 month and recipes. Follow-ups were at 2 weeks and 1 month. The primary outcome was the difference in glycaemic control between groups, analysed with a 95% confidence interval (CI) and P < 0.05 significance.

RESULTS

Of the 219 participants who completed the study (97.8%), adherence was 77.6% in the MOD group and 78.5% in the Enhanced MNT group. In an intention-to-treat analysis, an additional 11.6% (95% CI: -1.5% to 24.7%) in the MOD group achieved glycaemic control compared to the Enhanced MNT group, which was not statistically significant (P = 0.083). However, the MOD group had a significant mean post-prandial blood glucose reduction of -4.55 (95% CI: -8.55 to -0.56; P = 0.025).

CONCLUSION

Both interventions effectively controlled glycaemic levels, with the MOD group showing slightly better post-prandial glucose control. Adherence to the protocol was high.

TRIAL REGISTRATION

CTRI Registry CTRI/2022/04/042013.

Maternal Dietary Carbohydrate and Pregnancy Outcomes: Quality over Quantity

Dietary nutrition plays a crucial role in determining pregnancy outcomes, with poor diet being a major contributor to pregnancy metabolic syndrome and metabolic disorders in offspring. While carbohydrates are essential for fetal development, the excessive consumption of low-quality carbohydrates can increase the risk of pregnancy complications and have lasting negative effects on offspring development. Recent studies not only highlighted the link between carbohydrate intake during pregnancy, maternal health, and offspring well-being, but also suggested that the quality of carbohydrate foods consumed is more critical. This article reviews the impacts of low-carbohydrate and high-carbohydrate diets on pregnancy complications and offspring health, introduces the varied physiological effects of different types of carbohydrate consumption during pregnancy, and emphasizes the importance of both the quantity and quality of carbohydrates in nutritional interventions during pregnancy. These findings may offer valuable insights for guiding dietary interventions during pregnancy and shaping the future development of carbohydrate-rich foods.

Impact of carbohydrate quantity and quality on maternal and pregnancy outcomes in gestational diabetes mellitus: A systematic review and meta-analysis

OBJECTIVE

To evaluate the impact of carbohydrate quantity and quality on maternal and pregnancy outcomes in gestational diabetes mellitus.

METHODS

Using a pre-defined search strategy, two researchers systematically searched MEDLINE, CINAHL Plus, and PubMed for randomized controlled trials comparing low-carbohydrate, low-glycaemic index, or low-glycaemic load diets with usual care in gestational diabetes mellitus. Mean differences and risk ratios were extracted.

RESULTS

Thirteen studies with 877 participants were included. Low-carbohydrate diet did not significantly differ from usual care for fasting blood glucose (3 studies; mean difference: 1.60 mmol/L; 95 % confidence interval: -1.95, 5.15), insulin requirement (2 studies; risk ratio: 1.01; 95 % confidence interval: 0.31, 3.05), birthweight (4 studies; mean difference: -0.23 kg; 95 % confidence interval: -1.90, 1.45), caesarean delivery (5 studies; risk ratio: 1.11; 95 % confidence interval: 0.66, 1.85), macrosomia (3 studies; risk ratio: 0.35; 95 % confidence interval: 0.00, 2130.64), large-for-gestational-age (2 studies; risk ratio: 0.46; 95 % confidence interval: 0.03, 7.20), and small-for-gestational-age infants (2 studies; risk ratio: 0.94; 95 % confidence interval: 0.00, 231.18). Low-glycaemic index diet did not significantly differ from usual care for the above outcomes either. However, low-glycaemic load diet reduced macrosomia risk (2 studies; risk ratio: 0.51; 95 % confidence interval: 0.43, 0.59).

CONCLUSIONS

Low-carbohydrate and low-glycaemic index diets do not differ from usual care for most maternal and foetal outcomes in gestational diabetes mellitus. But low-glycaemic load diet may reduce macrosomia risk.

Effects of different dietary patterns during pregnancy on birth outcomes and glucose parameters in women with gestational diabetes mellitus: A systematic review and meta-analysis

PURPOSE

Dietary interventions are the cornerstone of gestational diabetes mellitus (GDM) treatment. This study aimed to evaluate the effects of dietary patterns during pregnancy on birth outcomes and glucose parameters in women with GDM.

METHODS

PubMed, Embase, and The CoChrane Library were searched from the time of database creation to November 30, 2021, along with manual searches. Data analyses were performed using Stata 15.4 software.

RESULTS

From 2461 studies, 27 RCTs involving 1923 women were eligible. The pooled results showed that dietary pattern interventions during pregnancy reduced birth weight (WMD: -0.14 kg; 95% CI: -0.24, -0.00), hemoglobin A_1 C (HbA_1 C) (WMD: -0.19, 95% CI: -0.34, -0.05), and macrosomia incidence (RR 0.65 [95% CI 0.48, 0.88]). Low glycemic index (GI) diet reduced macrosomia incidence (RR 0.31 [95% CI 0.11, 0.93]) and fasting plasma glucose (FPG) levels (WMD: -0.10 mmol/L; 95% CI: -0.14, -0.05); a low carbohydrate (CHO) diet reduced large for gestational age (LGA) incidence (RR 0.33 [95% CI 0.13, 0.82]) and HbA_1 C (WMD: -0.32; 95% CI: -0.51, -0.14); dietary approaches to stop hypertension (DASH) diet reduced birth weight (WMD:-0.59 kg; 95% CI: -0.64, -0.55), insulin use (RR 0.31 [95% CI 0.18, 0.56), macrosomia incidence (RR 0.12 [95% CI 0.03, 0.50]), and cesarean sections incidence (RR 0.57 [95% CI 0.40, 0.82]).

CONCLUSION

Dietary patterns during pregnancy can improve certain birth outcomes and glycemic parameters. Due to limitations in the quality and number of included studies, the above findings still need to be validated by further randomized controlled trials with high quality and large samples.

Glycemic responses to whole grain sourdough bread versus refined white bread in patients with gestational diabetes

BACKGROUND

Nutritional therapy remains a key tool for prevention and management of gestational diabetes (GDM). Carbohydrate type and absorption rate rather than the carbohydrate amount have more impact on postprandial glucose (PPG) levels in GDM. The effect of refined white bread and whole grain sourdough bread on glycemic indexes were compared in GDM patients.

METHODS

A total of 43 patients with GDM and 38 healthy pregnant women were included. A similar breakfast menu was given to both groups of patients at two different times in consecutive weeks; however, different types of bread with the same weight were used for both breakfasts; 1) white wheat (WW) bread, 2) sourdough whole grain wheat (SWGW) bread. Blood glucose, insulin and C‑peptide levels were compared before and after breakfast.

RESULTS

Fasting glucose, insulin and c‑peptide levels were similar between groups (p > 0.05). While the second hour glucose levels were similar between the groups, the first hour results of glucose, insulin and C‑peptide levels were lower in the SWGW group (p < 0.05). In the control patients, first hour glucose, insulin and C‑peptide levels were also lower in the SWGW group (p < 0.05).

CONCLUSION

The WW bread, which is more preferred in daily life routine, causes 45.5% more insulin secretion and 9.6% more first hour postprandial blood glucose compared to SWGW bread both in GDM patients and healthy pregnant women. According to the results of this study, we recommend that sourdough whole grain bread should be preferred in order to increase the success in the management of GDM.

Physical Activity, but Not Glycaemic Load, Is Associated with Lower Real-Time Glycaemic Control in Free-Living Women with Gestational Diabetes Mellitus

Maintaining blood glucose within the target range is the primary treatment goal for women with gestational diabetes mellitus (GDM). Foods with low glycaemic loads are recommended in clinical practice; however, the relative importance of other key lifestyle variables is unexplored. This pilot study explored the associations of glycaemic load, carbohydrates and physical activity parameters on blood glucose concentrations in free-living women with GDM. Twenty-nine women (28-30 weeks gestation, 34 ± 4 years) with GDM were enrolled. Continuous glucose monitoring, physical activity (ActivPAL inclinometer) and dietary intake and dietary quality were measured concurrently for 3 days. Pearson correlation analyses determined the association between glucose levels and lifestyle variables. Despite all receiving the same nutrition education, only 55% of women were following a low glycaemic load diet with a large range of carbohydrate intakes (97-267 g/day). However, the glycaemic load did not correlate with 3-hr postprandial glucose (r² = 0.021, p = 0.56) or 24-h glucose iAUC (r² = 0.021, p = 0.58). A significant relationship between total stepping time and lower 24-h glucose iAUC (r² = 0.308, p = 0.02) and nocturnal glucose (r² = 0.224, p = 0.05) was found. In free-living women with diet-controlled GDM, more physical activity, i.e., steps accumulated across the day, may be a simple and effective strategy for improving maternal blood glucose concentrations.

Effects of the Consumption of Low to Medium Glycemic Index-Based Rice on the Rate of Insulin Initiation in Patients with Gestational Diabetes: A Triple-blind, Randomized, Controlled Trial

INTRODUCTION

Medical nutritional therapy is vital in patients with diabetes. A low glycemic index (GI) is generally advised in the management of women with gestational diabetes mellitus (GDM). However, the efficacy of this advice has not been systematically examined. The purpose of this study was to determine whether recommending a low to moderate GI rice (RD43 rice; GI = 56.9) in women with GDM would reduce the number of women requiring insulin, compared with rice of high GI (Thai Hom Mali [THM] rice; GI = 80.1).

METHODS

Ninety-six participants with GDM were randomly assigned to receive either RD43 rice or THM rice.

RESULTS

The mean ± SD ages in the RD43 and THM groups were 33.1 ± 13.1 and 33.6 ± 4.1 years, respectively. The mean gestational ages at the sampling in the RD43 and THM groups were 23.3 ± 5.9 and 23.5 ± 5.4 weeks. Both groups had comparable baseline characteristics, including age, gestational age, body mass index prior to pregnancy and at enrollment, baseline postprandial (oral glucose tolerance test) plasma glucose level, and hemoglobin A_1c. Of the 48 women assigned to the RD43 group, 3 (6.3%) required insulin; in the THM group, 11 (22.9%) met the criteria for insulin therapy (P = 0.017). However, 10 of these 11 women were able to avoid insulin use by changing to the low to moderate GI rice.

CONCLUSION

Using a low to moderate GI rice in GDM effectively reduced the number of patients requiring insulin therapy. Thai Clinical Trials Registry ID: TCTR20210524007.

Fasting Glucose Level on the Oral Glucose Tolerance Test Is Associated with the Need for Pharmacotherapy in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) has a rapidly increasing prevalence, which poses challenges to obstetric care and service provision, with known serious long-term impacts on the metabolic health of the mother and the affected offspring. The aim of this study was to evaluate the association between glucose levels on the 75 g oral glucose tolerance test and GDM treatment and outcomes. We performed a retrospective cohort study of women with GDM attending a tertiary Australian hospital obstetric clinic between 2013 and 2017, investigating the relationship between the 75 g oral glucose tolerance test (OGTT) glucose values, and obstetric (timing of delivery, caesarean section, preterm birth, preeclampsia), and neonatal (hypoglycaemia, jaundice, respiratory distress and NICU admission) outcomes. This time frame encompassed a change in diagnostic criteria for gestational diabetes, due to changes in international consensus guidelines. Our results showed that, based on the diagnostic 75 g OGTT, fasting hyperglycaemia, either alone or in combination with elevated 1 or 2 h glucose levels, was associated with the need for pharmacotherapy with either metformin and/or insulin (p < 0.0001; HR 4.02, 95% CI 2.88-5.61), as compared to women with isolated hyperglycaemia at the 1 or 2 h post-glucose load timepoints. Fasting hyperglycaemia on the OGTT was more likely in women with higher BMI (p < 0.0001). There was an increased risk of early term birth in women with mixed fasting and post-glucose hyperglycaemia (adjusted HR 1.72, 95% CI 1.09-2.71). There were no significant differences in rates of neonatal complications such as macrosomia or NICU admission. Fasting hyperglycaemia, either alone or in combination with post-glucose elevations on the OGTT, is a strong indicator of the need for pharmacotherapy in pregnant women with GDM, with significant ramifications for obstetric interventions and their timing.

Community-based non-pharmacological interventions for pregnant women with gestational diabetes mellitus: a systematic review

BACKGROUND

Non-pharmacological interventions are the first line of Gestational diabetes mellitus (GDM) management. Community-based interventions are cheaper, more accessible, with higher patient satisfaction.

OBJECTIVES

To systematically review community-based non-pharmacological interventions and evaluate their effectiveness for GDM.

SEARCH STRATEGY

Twelve bibliographic databases and reference list of related studies from inception until January 2022.

SELECTION CRITERIA

All primary studies of community-based non-pharmacological interventions for GDM reported in English which investigated any behavioural or clinical outcome(s).

DATA COLLECTION AND ANALYSIS

Data were extracted using modified Cochrane's data extraction template. Studies were evaluated using Cochrane Collaboration's risk of bias tool. Narrative synthesis was used to summarise findings. This study is registered with PROSPERO (CRD42021257634).

MAIN RESULTS

Twenty-seven studies involving 6,242 pregnant women with GDM investigated self-management programmes, medical nutrition/diet therapy, exercise/physical activity, combined diet and exercise, calcium plus vitamin D supplementation, and continuous glucose monitoring. Self-management programmes were more effective than routine care in improving self-efficacy, two-hour postprandial blood glucose, and lifestyle behaviours but were as effective as routine care in improving infant birth weight. Self-management programmes were superior to or as effective as usual care in improving fasting blood glucose, blood glucose control, glycated haemoglobin, macrosomia, and preterm delivery. Medical nutrition/diet therapy was more effective than usual care in improving postprandial blood glucose levels. Postprandial blood glucose levels were better improved by regular supervised exercise plus daily brisk walks or a daily walking intervention than routine obstetric care or no treatment. The effects of exercise/physical activity programmes were mostly inconsistent for other outcomes. Diet and exercise were superior to diet alone in reducing maternal weight gain although there were similar outcomes for other pregnancy and foetal outcomes. Limited or conflicting evidence was found for other outcomes and interventions including calcium and vitamin D supplementation and continuous glucose monitoring intervention.

CONCLUSIONS

Community-based non-pharmacological interventions are more effective than placebo; and are more or as effective as usual care. Self-management programmes and medical nutrition/diet therapy had the most promising GDM outcomes.

FUNDING

There was no funding for this study. The study design, data collection, data analysis and interpretation, and writing of this manuscript were not influenced externally by any funder.

Low-Glycemic Index Diets as an Intervention in Metabolic Diseases: A Systematic Review and Meta-Analysis

We aimed to investigate the effects of a low-glycemic index (GI) diet on the body mass and blood glucose of patients with four common metabolic diseases by conducting a systematic review and meta-analysis of studies comparing a low-GI diet (LGID) and other types of diet. Search terms relating to population, intervention, comparator, outcomes, and study design were used to search three databases: PubMed, Embase, and the Cochrane Library. We identified 24 studies involving 2002 participants. Random-effects models were used for 16 studies in the meta-analysis and stratified analyses were performed according to the duration of the intervention. The systematic review showed that LGIDs slightly reduced body mass and body mass index (BMI) (p < 0.05). BMI improved more substantially after interventions of >24 weeks and there was no inter-study heterogeneity (I² = 0%, p = 0.48; mean difference (MD) = -2.02, 95% confidence interval (CI): -3.05, -0.98). Overall, an LGID had superior effects to a control diet on fasting blood glucose (FBG) and glycosylated hemoglobin. When the intervention exceeded 30 days, an LGID reduced FBG more substantially (MD = -0.34, 95% CI: -0.55, -0.12). Thus, for patients with metabolic diseases, an LGID is more effective at controlling body mass and blood glucose than a high-GI or other diet.

Effectivness of specific mobile health applications (mHealth-apps) in gestational diabtetes mellitus: a systematic review

BACKGROUND

Gestational diabetes mellitus (GDM) emerges worldwide and is closely associated with short- and long-term health issues in women and their offspring, such as pregnancy and birth complications respectively comorbidities, Type 2 Diabetes (T2D), metabolic syndrome as well as cardiovascular diseases. Against this background, mobile health applications (mHealth-Apps) do open up new possibilities to improve the management of GDM. Therefore, we analyzed the clinical effectiveness of specific mHealth-Apps on clinical health-related short and long-term outcomes in mother and child.

METHODS

A systematic literature search in Medline (PubMed), Cochrane Library, Embase, CINAHL and Web of Science Core Collection databases as well as Google Scholar was performed. We selected studies published 2008 to 2020 analyzing women diagnosed with GDM using specific mHealth-Apps. Controlled clinical trials (CCT) and randomized controlled trials (RCT) were included. Study quality was assessed using the Effective Public Health Practice Project (EPHPP) tool.

RESULTS

In total, n = 6 publications (n = 5 RCTs, n = 1 CCT; and n = 4 moderate, n = 2 weak quality), analyzing n = 408 GDM patients in the intervention and n = 405 in the control groups, were included. Compared to control groups, fasting blood glucose, 2-h postprandial blood glucose, off target blood glucose measurements, delivery mode (more vaginal deliveries and fewer (emergency) caesarean sections) and patient compliance showed improving trends.

CONCLUSION

mHealth-Apps might improve health-related outcomes, particularly glycemic control, in the management of GDM. Further studies need to be done in more detail.

Searching for Utopia, the Challenge of Standardized Medical Nutrition Therapy Prescription in Gestational Diabetes Mellitus Management: A Critical Review

Gestational diabetes mellitus (GDM) is a common pregnancy disorder and the incidence is increasing worldwide. GDM is associated with adverse maternal outcomes which may be reduced with proper management. Lifestyle modification in the form of medical nutrition therapy and physical activity, as well as self-monitoring of blood glucose levels, is the cornerstone of GDM management. Inevitably, the search for the "ultimate" diet prescription has been ongoing. Identifying the amount and type of carbohydrate to maintain blood glucose levels below targets while balancing the nutritional requirements of pregnancy and achieving gestational weight gain within recommendations is challenging. Recent developments in the area of the gut microbiota and its impact on glycemic response add another layer of complexity to the success of medical nutrition therapy. This review critically explores the challenges to dietary prescription for GDM and why utopia may never be found.

An Update of Medical Nutrition Therapy in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a serious and frequent pregnancy complication that can lead to short and long-term risks for both mother and fetus. Different health organizations proposed different algorithms for the screening, diagnosis, and management of GDM. Medical Nutrition Therapy (MNT), together with physical exercise and frequent self-monitoring, represents the milestone for GDM treatment in order to reduce maternal and fetal complications. The pregnant woman should benefit from her family support and make changes in their lifestyles, changes that, in the end, will be beneficial for the whole family. The aim of this manuscript is to review the literature about the Medical Nutrition Therapy in GDM and its crucial role in GDM management.

Low-Carbohydrate Diets for Gestational Diabetes

Nutrition therapy provides the foundation for treatment of gestational diabetes (GDM), and has historically been based on restricting carbohydrate (CHO) intake. In this paper, randomized controlled trials (RCTs) are reviewed to assess the effects of both low- and higher CHO nutrition approaches in GDM. The prevailing pattern across the evidence underscores that although CHO restriction improves glycemia at least in the short-term, similar outcomes could be achievable using less restrictive approaches that may not exacerbate IR. The quality of existing studies is limited, in part due to dietary non-adherence and confounding effects of treatment with insulin or oral medication. Recent evidence suggests that modified nutritional manipulation in GDM from usual intake, including but not limited to CHO restriction, improves maternal glucose and lowers infant birthweight. This creates a platform for future studies to further clarify the impact of multiple nutritional patterns in GDM on both maternal and infant outcomes.

Gestational Diabetes Mellitus: The Impact of Carbohydrate Quality in Diet

Gestational diabetes mellitus (GDM) is defined as “glucose intolerance that is first diagnosed during pregnancy”. Mothers with GDM and their infants may experience both short and long term complications. Dietary intervention is the first therapeutic strategy. If good glycaemic control is not achieved, insulin therapy is recommended. There is no consensus on which nutritional approach should be used in GDM. In the last few years, there has been growing evidence of the benefits of a low glycaemic index (LGI) diet on diabetes and cardiovascular disease. The effect of a LGI diet on GDM incidence has been investigated as well. Several studies observed a lower incidence of GDM in LGI diet arms, without adverse maternal and fetal outcomes. The main positive effect of the LGI diet was the reduction of 2-h post-prandial glucose (PPG). Several studies have also evaluated the effect of the LGI diet in GDM treatment. Overall, the LGI diet might have beneficial effects on certain outcomes, such as 2-h PPG, fasting plasma glucose and lipid profile in patients with GDM. Indeed, most studies observed a significant reduction in insulin requirement. Overall, according to current evidence, the LGI nutritional approach is safe and it might therefore be considered in clinical care for GDM.

Effectiveness of Low Glycemic Index Diet Consultations Through a Diet Glycemic Assessment App Tool on Maternal and Neonatal Insulin Resistance: A Randomized Controlled Trial

Background

Low glycemic index (LGI) diet has shown to be effective in reducing maternal and neonatal complications in high-risk pregnancies.

Objective

This trial aimed to examine the effectiveness of individualized LGI diet consultations based on the accurate diet glycemic load (GL) assessment tool on maternal and neonatal insulin resistance levels and diet behavior changes in overweight and obese pregnant women.

Methods

Overweight and obese pregnant women were recruited before 16 weeks of gestation and randomized to the LGI diet arm or the control arm. All participants received standard dietary education according to the Chinese Dietary Guide for Pregnant Women. In the intervention arm, additional individualized dietary GL assessments were performed using an app and instructions of lowering diet glycemic index (GI) to achieve LGI diet were provided by a clinical dietitian at early, middle, and late gestation. Primary outcomes were serum insulin at late gestation, incidence of gestational diabetes mellitus (GDM) for mothers, and cord blood C-peptide level of neonates.

Results

In total, 400 subjects were randomized and received different interventions. There were no significant differences in maternal serum insulin levels (13.2 [9.3−13.2] uU/mL vs 12.4 [10.5−12.4] uU/mL), incidence of GDM (45 [22.5%] vs 43 [21.5%]), or cord blood C-peptide levels (mean 0.9ng/mL [SD 0.7] vs mean 0.8ng/mL [SD 0.6]) in the intervention group compared with the controls. The diet GI at late gestation was similar (mean 63.2 [SD 10.4] vs mean 64.3 [SD 10.4]), whereas greater diet fiber intake was observed in the intervention group (mean 11.6 grams [SD 8.0] vs mean 9.0 grams [SD 5.6]; P=.006). Adherence measurements did not significantly differ between 2 groups.

Conclusions

Individualized LGI diet consultations for overweight and obese pregnant women failed to make a significant difference in maternal or neonatal insulin resistance compared with the standard gestational diet consultation.

Trial Registration

ClinicalTrials.gov NCT01628835; http://clinicaltrials.gov/ct2/show/NCT01628835 (Archived by WebCite at http://www.webcitation.org/77LHgWP0k)

Dietary intervention strategies for ethnic Chinese women with gestational diabetes mellitus: A systematic review and meta-analysis

AIM

Ethnic Chinese women are one of the populations at high risk of gestational diabetes mellitus (GDM) internationally. This systematic review aimed to determine which dietary intervention strategies were found to be effective in improving glycaemic control and pregnancy outcomes among ethnic Chinese women with GDM.

METHODS

The review protocol was registered with PROSPERO (CRD42016043585). Eight English and four Chinese language databases were searched for randomised controlled trials and cohort studies of dietary intervention among ethnic Chinese women with GDM. Review Manager 5.3 and GRADE criteria were used in meta-analysis and assessment of quality of evidence.

RESULTS

Included studies comprised 3944 women in 29 eligible studies. Compared to standard treatment, low glycaemic index (GI) diets, low glycaemic load (GL) diets and fibre-enriched diets were associated with a reduction in fasting plasma glucose, 2-hour plasma glucose and HbA1c, and improved neonatal outcomes. Low GL diets were associated with reduced caesarean section risk.

CONCLUSIONS

In ethnic Chinese women with GDM, low GI diets, low GL diets and fibre-enriched diets were associated with improved glycaemic control and pregnancy outcomes. Given the lack of direct comparison of these three diets, future direct comparison trials are necessary to determine optimal dietary intervention strategies.

How diet, physical activity and psychosocial well-being interact in women with gestational diabetes mellitus: an integrative review

Background

Gestational Diabetes Mellitus (GDM) is associated with future cardio-metabolic risks for the mother and her child. In addition, one-third of women with recent GDM develop postpartum depression. Given these adverse impacts of GDM on the health of the mother and her offspring, it is important to intervene on modifiable factors, such as diet, physical activity, and psychosocial well-being. This integrative review therefore explored evidence on how these modifiable factors interact in women with GDM and their offspring, and how effective combined interventions are on reducing adverse impacts of GDM.

Methods

A comprehensive search strategy included carefully selected terms that corresponded to the domains of interest (diet, physical activity and psychosocial well-being). The databases searched for articles published between 1980 and February 2018 were: CINAHL, PsycINFO, Embase, Pubmed and Cochrane. Studies that were included in this review were either observational or intervention studies that included at least two domains of interest. Articles had to at least report data on maternal outcomes of women with GDM.

Results

The search strategies identified 14′419 citations after excluding duplicates. After screening titles and then abstracts, 114 articles were selected for detailed evaluation of their full text, and 16 were included in this review: two observational and 14 intervention studies. Results from observational studies showed that psychosocial well-being (social support and self-efficacy) were positively associated with physical activity and dietary choice. Intervention studies always included diet and physical activity interventions, although none integrated psychosocial well-being in the intervention. These lifestyle interventions mostly led to increased physical activity, improved diet and lower stress perception. Many of these lifestyle interventions also reduced BMI and postpartum diabetes status, improved metabolic outcomes and reduced the risk of preterm deliveries and low birth weight.

Conclusion

This integrative review showed that psychosocial well-being interacted with diet as well as with physical activity in women with GDM. We recommend that future studies consider integrating psychosocial well-being in their intervention, as observational studies demonstrated that social support and self-efficacy helped with adopting a healthy lifestyle following GDM diagnosis.

Electronic supplementary material

The online version of this article (10.1186/s12884-019-2185-y) contains supplementary material, which is available to authorized users.

Nutrition therapy within and beyond gestational diabetes

With the global rising prevalence of gestational diabetes (GDM), an adaptable, economical approach to nutrition therapy that effectively controls maternal glycemia while promoting normal fetal growth will have far-reaching implications. The conventional focus has been to rigidly limit all types of carbohydrate. While controlling glucose, this approach fosters maternal anxiety and is a primary barrier to adherence. Many mothers substitute fat for carbohydrate, which may unintentionally enhance lipolysis, promote elevated free fatty acids (FFA), and worsen maternal insulin resistance (IR). Nutrition that worsens IR may facilitate nutrient shunting across the placenta, promoting excess fetal fat accretion. Evidence suggests that liberalizing higher quality, nutrient-dense carbohydrates results in controlled fasting/postprandial glucose, lower FFA, improved insulin action, vascular benefits, and may reduce excess infant adiposity. Thus, a less carbohydrate-restricted approach may improve maternal adherence when combined with higher quality carbohydrates, lower fat, appropriate caloric intake, and ethnically acceptable foods. Such a diet can be culturally sensitive, socioeconomically attentive, minimize further weight gain in GDM, with potential relevance for pregnancies complicated by overweight/obesity. Future research is needed to better understand the effect of macronutrient composition on the placenta and gut microbiome, the benefits/risks of nonnutritive sweeteners, and whether precision-nutrition is beneficial in pregnancy.

Influence of low-glycemic index diet for gestational diabetes: a meta-analysis of randomized controlled trials

Background: Low-glycemic index (GI) diet might be beneficial for gestational diabetes. However, the results remained controversial. We conducted a systematic review and meta-analysis to explore the influence of low-GI diet on gestational diabetes.Methods: PubMed, EMbase, Web of Science, EBSCO, and Cochrane library databases were systematically searched. Randomized controlled trials (RCTs) assessing the effect of low-GI diet on gestational diabetes were included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. This meta-analysis was performed using the random-effect model.Results: Six RCTs involving 532 patients were included in the meta-analysis. Overall, compared with a control intervention in gestational diabetes, low-GI diet was found to significantly reduce 2 h postprandial glucose (Std. MD = -0.46; 95% CI = -0.82 to -0.10; p = .01), but demonstrated no substantial influence on fasting plasma glucose (Std. MD = -0.24; 95% CI = -0.72 to 0.24; p = .33), HbA1c (Std. MD = 0.01; 95% CI = -0.29 to 0.31; p = .94), birth weight (Std. MD = -0.17; 95% CI = -0.41 to 0.06; p = .15), macrosomia (Std. MD = 0.45; 95% CI = 0.16 to 1.30; p = .14) and insulin requirement (Std. MD = 0.91; 95% CI = 0.68 to 1.22; p = .55).Conclusions: Compared with control intervention in gestational diabetes, low-GI diet was found to significantly decrease 2 h postprandial glucose, but showed no notable impact on fasting plasma glucose, HbA1c, birth weight, macrosomia, and insulin requirement.

Glycemic index, glycemic load, and glycemic response to pomelo in patients with type 2 diabetes

Food intake has a great influence on blood glucose in patients with diabetes. This study was to determine the glycemic index (GI) and glycemic load (GL) of a particular pomelo named Majia pomelo and its effects on postprandial glucose (PPG) in patients with type 2 diabetes (T2D). Twenty healthy subjects and 20 T2D patients (controlled on lifestyle measures and/or metformin) were tested on 2 separate days with 50 g of glucose and 50 g equivalent of carbohydrates from Majia pomelo for GI measurement. To test effects of Majia pomelo on PPG, 19 hospitalized T2D patients (controlled on insulin therapy) were selected for a 9-day study. The dose of insulin for each patient was adjusted on the first 3 days. A total of 100 mg Majia pomelo was consumed per meal in the last 3 tested days. Blood glucose was measured to evaluate the glycemic excursions. The GIs for Majia pomelo in healthy individuals and T2D patients were 78.34±1.88 and 72.15±1.95 respectively. The value of GL was as low as 4.23 in diabetic patients with serving size of 100 g pomelo, indicting Majia pomelo as a high GI but low GL fruit. Consumption of Majia pomelo in hospitalized T2D patients did not cause significant glucose fluctuation. It was concluded that high GI pomelo can serve as a low GL fruit if it is consumed with a limited daily amount and thus can be supplied to diabetic patients. These results may mean more varieties of food choices for T2D patients.

A systematic review of interventions for Hispanic women with or at risk of Gestational diabetes mellitus (GDM)

BACKGROUND AND OBJECTIVE

Gestational Diabetes Mellitus (GDM) is a serious health concern for pregnant women, with Hispanic women at particular risk for developing the condition. The aim of this review was to critically examine GDM intervention programs for Hispanic women, in the United States of America (US).

METHODS

English and Spanish electronic databases were searched for relevant studies published between 1995 and 2015. Eligible study designs included randomized controlled trial, pre/post-test and quasi experimental methods.

RESULTS

Findings indicated that there was a dearth of literature reporting on GDM interventions for Hispanic women and just seven papers met inclusion criteria. These seven studies were included in the review and they reported on interventions for: (1) pregnant women at high risk of developing GDM; (2) pregnant women with GDM. Results suggest that a combination of intensive counselling over a prolonged period of time, together with a low calorie, possibly low glycemic index diet, produces best results.

CONCLUSION

The review found that intensive nutritional counselling approaches which promote low calorie/low GI diets appear to be most effective in BGL management in this population. Interventions that are delivered in Spanish and culturally tailored may be more acceptable to participants. More research is needed to develop suitable interventions to improve GDM management among Hispanic women.

Different types of dietary advice for women with gestational diabetes mellitus

BACKGROUND

Dietary advice is the main strategy for managing gestational diabetes mellitus (GDM). It remains unclear what type of advice is best.

OBJECTIVES

To assess the effects of different types of dietary advice for women with GDM for improving health outcomes for women and babies.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (8 March 2016), PSANZ's Trials Registry (22 March 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials comparing the effects of different types of dietary advice for women with GDM.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility, risk of bias, and extracted data. Evidence quality for two comparisons was assessed using GRADE, for primary outcomes for the mother: hypertensive disorders of pregnancy; caesarean section; type 2 diabetes mellitus; and child: large-for-gestational age; perinatal mortality; neonatal mortality or morbidity composite; neurosensory disability; secondary outcomes for the mother: induction of labour; perineal trauma; postnatal depression; postnatal weight retention or return to pre-pregnancy weight; and child: hypoglycaemia; childhood/adulthood adiposity; childhood/adulthood type 2 diabetes mellitus.

MAIN RESULTS

In this update, we included 19 trials randomising 1398 women with GDM, at an overall unclear to moderate risk of bias (10 comparisons). For outcomes assessed using GRADE, downgrading was based on study limitations, imprecision and inconsistency. Where no findings are reported below for primary outcomes or pre-specified GRADE outcomes, no data were provided by included trials. Primary outcomes Low-moderate glycaemic index (GI) versus moderate-high GI diet (four trials): no clear differences observed for: large-for-gestational age (risk ratio (RR) 0.71, 95% confidence interval (CI) 0.22 to 2.34; two trials, 89 infants; low-quality evidence); severe hypertension or pre-eclampsia (RR 1.02, 95% CI 0.07 to 15.86; one trial, 95 women; very low-quality evidence); eclampsia (RR 0.34, 95% CI 0.01 to 8.14; one trial, 83 women; very low-quality evidence) or caesarean section (RR 0.66, 95% CI 0.29 to 1.47; one trial, 63 women; low-quality evidence). Energy-restricted versus no energy-restricted diet (three trials): no clear differences seen for: large-for-gestational age (RR 1.17, 95% CI 0.65 to 2.12; one trial, 123 infants; low-quality evidence); perinatal mortality (no events; two trials, 423 infants; low-quality evidence); pre-eclampsia (RR 1.00, 95% CI 0.51 to 1.97; one trial, 117 women; low-quality evidence); or caesarean section (RR 1.12, 95% CI 0.80 to 1.56; two trials, 420 women; low-quality evidence). DASH (Dietary Approaches to Stop Hypertension) diet versus control diet (three trials): no clear differences observed for: pre-eclampsia (RR 1.00, 95% CI 0.31 to 3.26; three trials, 136 women); however there were fewer caesarean sections in the DASH diet group (RR 0.53, 95% CI 0.37 to 0.76; two trials, 86 women). Low-carbohydrate versus high-carbohydrate diet (two trials): no clear differences seen for: large-for-gestational age (RR 0.51, 95% CI 0.13 to 1.95; one trial, 149 infants); perinatal mortality (RR 3.00, 95% CI 0.12 to 72.49; one trial, 150 infants); maternal hypertension (RR 0.40, 95% CI 0.13 to 1.22; one trial, 150 women); or caesarean section (RR 1.29, 95% CI 0.84 to 1.99; two trials, 179 women). High unsaturated fat versus low unsaturated fat diet (two trials): no clear differences observed for: large-for-gestational age (RR 0.54, 95% CI 0.21 to 1.37; one trial, 27 infants); pre-eclampsia (no cases; one trial, 27 women); hypertension in pregnancy (RR 0.54, 95% CI 0.06 to 5.26; one trial, 27 women); caesarean section (RR 1.08, 95% CI 0.07 to 15.50; one trial, 27 women); diabetes at one to two weeks (RR 2.00, 95% CI 0.45 to 8.94; one trial, 24 women) or four to 13 months postpartum (RR 1.00, 95% CI 0.10 to 9.61; one trial, six women). Low-GI versus high-fibre moderate-GI diet (one trial): no clear differences seen for: large-for-gestational age (RR 2.87, 95% CI 0.61 to 13.50; 92 infants); caesarean section (RR 1.91, 95% CI 0.91 to 4.03; 92 women); or type 2 diabetes at three months postpartum (RR 0.76, 95% CI 0.11 to 5.01; 58 women). Diet recommendation plus diet-related behavioural advice versus diet recommendation only (one trial): no clear differences observed for: large-for-gestational age (RR 0.73, 95% CI 0.25 to 2.14; 99 infants); or caesarean section (RR 0.78, 95% CI 0.38 to 1.62; 99 women). Soy protein-enriched versus no soy protein diet (one trial): no clear differences seen for: pre-eclampsia (RR 2.00, 95% CI 0.19 to 21.03; 68 women); or caesarean section (RR 1.00, 95% CI 0.57 to 1.77; 68 women). High-fibre versus standard-fibre diet (one trial): no primary outcomes reported. Ethnic-specific versus standard healthy diet (one trial): no clear differences observed for: large-for-gestational age (RR 0.14, 95% CI 0.01 to 2.45; 20 infants); neonatal composite adverse outcome (no events; 20 infants); gestational hypertension (RR 0.33, 95% CI 0.02 to 7.32; 20 women); or caesarean birth (RR 1.20, 95% CI 0.54 to 2.67; 20 women). Secondary outcomes For secondary outcomes assessed using GRADE no differences were observed: between a low-moderate and moderate-high GI diet for induction of labour (RR 0.88, 95% CI 0.33 to 2.34; one trial, 63 women; low-quality evidence); or an energy-restricted and no energy-restricted diet for induction of labour (RR 1.02, 95% CI 0.68 to 1.53; one trial, 114 women, low-quality evidence) and neonatal hypoglycaemia (average RR 1.06, 95% CI 0.48 to 2.32; two trials, 408 infants; very low-quality evidence).Few other clear differences were observed for reported outcomes. Longer-term health outcomes and health services use and costs were largely not reported.

AUTHORS' CONCLUSIONS

Evidence from 19 trials assessing different types of dietary advice for women with GDM suggests no clear differences for primary outcomes and secondary outcomes assessed using GRADE, except for a possible reduction in caesarean section for women receiving a DASH diet compared with a control diet. Few differences were observed for secondary outcomes.Current evidence is limited by the small number of trials in each comparison, small sample sizes, and variable methodological quality. More evidence is needed to assess the effects of different types of dietary advice for women with GDM. Future trials should be adequately powered to evaluate short- and long-term outcomes.

Effects of low-glycemic-index diets in pregnancy on maternal and newborn outcomes in pregnant women: a meta-analysis of randomized controlled trials

PURPOSE

Maternal diet with a high glycemic index (GI) is associated with fetal overgrowth and higher infant body adiposity. Effects of low-GI diet on maternal and newborn outcomes have been assessed in both healthy pregnancy and gestational diabetes mellitus, but the results remain inconclusive. This meta-analysis aimed to examine the effects of low-GI diets on maternal and newborn outcomes.

METHODS

PubMed, Clinical Trials, and Cochrane Library databases were searched for relevant randomized trials up to January 2016. Random- or fixed-effects models were used to calculate combined treatment effects.

RESULTS

A total of 11 trials involving 1985 women were eligible for analysis. This meta-analysis assessed 7 maternal and 11 newborn outcomes. Of these, gestational weight gain (GWG), fasting blood glucose (FBG), newborn birth weight, ponderal index (PI), proportion of macrosomia, and large for gestational age (LGA) were investigated in more than 8 trials. Compared with control diets, low-GI diets significantly reduced FBG (weight mean differences (WMD) = -0.18 mmol/L, 95 % CI: -0.33, -0.02), 2-h postprandial glucose level (WMD = -0.33 mmol/L, 95 % CI: -0.54, -0.12), and the proportion of LGA (RR = 0.52, 95 % CI: 0.31, 0.89). A lower GWG (WMD = -0.69 kg, 95 % CI: -1.74, 0.36) and birth weight (WMD = -0.10 kg, 95 % CI: -0.23, 0.03) were also observed without significant differences. Heterogeneity was observed in the GWG, FBG, and birth weight analyses. Low-GI diets did not affect other maternal and newborn outcomes. In subgroup and sensitivity analyses, the intervention effects of low GI on GWG and FBG varied.

CONCLUSIONS

Low-GI diets may have beneficial effects on maternal outcomes for those at risk of developing high glucose levels, without causing adverse effects on newborn outcomes. However, results should be interpreted with caution because of the evidence of heterogeneity and limited number of studies.