Factors associated with dietary glycemic index and glycemic load in pregnant women and risk for gestational diabetes mellitus

Endocrine disrupting chemicals: gestational diabetes and beyond

Gestational Diabetes Mellitus (GDM) has been on the rise for the last two decades along with the growing incidence of obesity. The ubiquitous use of Endocrine-Disrupting Chemicals (EDCs) worldwide has been associated with this increase in GDM incidence. Epigenetic modifications such as DNA methylation, histone acetylation, and methylation have been associated with prenatal exposure to EDCs. EDC exposure can also drive a sustained disruption of the hypothalamus-pituitary-thyroid axis and various other signaling pathways such as thyroid signaling, PPARγ signaling, PI3K-AKT signaling. This disruption leads to impaired glucose metabolism, insulin resistance as well as β-cell dysfunction, which culminate into GDM. Persistent EDC exposure in pregnant women also increases adipogenesis, which results in gestational weight gain. Importantly, pregnant mothers transfer these EDCs to the fetus via the placenta, thus leading to other pregnancy-associated complications such as intrauterine growth restriction (IUGR), and large for gestational age neonates. Furthermore, this early EDC exposure of the fetus increases the susceptibility of the infant to metabolic diseases in early life. The transgenerational impact of EDCs is also associated with higher vascular tone, cognitive aberrations, and enhanced susceptibility to lifestyle disorders including reproductive health anomalies. The review focuses on the impact of environmental toxins in inducing epigenetic alterations and increasing the susceptibility to metabolic diseases during pregnancy needs to be extensively studied such that interventions can be developed to break this vicious cycle. Furthermore, the use of EDC-associated ExomiRs from the serum of patients can help in the early diagnosis of GDM, thereby leading to triaging of patients based on increasing risk factor of the clinicopathological condition.

Preconception dietary glycemic index and risk for large-for-gestational age births

OBJECTIVES

Diets with a high glycemic index (GI) leading to elevated postprandial glucose levels and hyperinsulinemia during pregnancy have been inconsistently linked to an increased risk for large-for-gestational-age (LGA) births. The effects of prepregnancy dietary GI on LGA risk are, to our knowledge, unknown. We examined the association of prepregnancy dietary GI with LGA births and joint associations of GI and maternal overweight/obesity and infant sex with LGA births among 10 188 infants born without congenital anomalies from 1997 to 2011, using data from the National Birth Defects Prevention Study (NBDPS). The aim of this study was to investigate this association among infants without major congenital anomalies (controls) who participated in the NBDPS and to evaluate how prepregnancy BMI and infant sex may modify this association on the additive scale.

METHODS

Dietary intake was ascertained using a 58-item food frequency questionnaire. We dichotomized dietary GI into high and low categories using spline regression models. Infants with a birth weight at or above the 90th percentile for gestational age and sex, according to a U.S. population reference, were considered LGA. We used logistic regression to obtain odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Of the infants, 859 (9%) had a high dietary GI (cut-point: 59), and 1244 infants (12%) were born LGA. Unadjusted analysis suggested an inverse association between high dietary GI and LGA (OR, 0.79; 95% CI, 0.62-0.99). No association was observed in multivariable models when comparing high dietary GI intake between LGA births and all other births (OR, 0.94; 95% CI, 0.74-1.20) or when excluding small-for-gestational-age (SGA) births (OR, 0.94; 95% CI, 0.73-1.19). No joint associations with maternal overweight/obesity or infant sex were observed.

CONCLUSION

High prepregnancy maternal GI was not associated with LGA births independently of or jointly with other factors.

The Role of the Glycemic Index and Glycemic Load in the Dietary Approach of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a common metabolic disorder that often develops during pregnancy, characterized by glucose intolerance and insulin resistance (IR). To ensure the well-being of both the mother and the fetus, the body undergoes multiple metabolic and immunological changes that result in peripheral IR and, under certain hereditary or acquired abnormalities, GDM in predisposed women. The adverse short- and long-term effects of GDM impact both the mother and the fetus. Nutrition seems to play an important role to prevent GDM or improve its evolution. An emphasis has been given to the proportion of carbohydrates (CHO) relative to protein and lipids, as well as dietary patterns, in GDM. The effects of CHO on postprandial glucose concentrations are reflected in the glycemic index (GI) and glycemic load (GL). Diets rich in GI and GL may induce or exacerbate IR, whereas diets low in GI and GL appear to enhance insulin sensitivity and improve glycemic control. These positive outcomes may be attributed to direct interactions with insulin and glucose homeostasis or indirect effects through improved body composition and weight management. This comprehensive narrative review aims to explore the significance of nutrition, with a focus on the critical evaluation of GI and GL in the dietary management of women with GDM.

Effect of low-glycemic index diet advice on pregnant outcomes in women with elevated risk of gestational diabetes mellitus: A meta-analysis of randomized controlled trails

BACKGROUND AND AIMS

The beneficial effect of low-glycemic index (GI) diet on gestational diabetes mellitus (GDM) has been suggested in many observational studies; however, results from intervention trials remain inconsistent. This study aims to estimate the effect of interventions with low-GI dietary advice on pregnant outcomes in women with elevated risk of GDM.

DESIGN

PubMed, Web of Science, Embase, and Cochrane Library databases were searched for randomized clinical trials (RCTs) through March 2022. Studies reporting the effect of low-GI diet advice intervention on maternal and fetal outcomes in pregnant women with increased risks of GDM were included. Random or fixed effects model was used to calculate combined treatment effects. Publication bias was assessed via Begg's and Egger's tests and funnel plot inspection.

RESULTS

Nine RCTs recruiting 3416 participants were included. Low-GI diet advice did not modulate the risk of GDM. Compared with control diets, low-GI diet advice significantly reduced gestational weight gain (GWG) (weighted mean differences, WMD = -0.93 kg, 95% CI: -1.31, -0.55; p < 0.001; n = 7) and the risk of premature birth (RR = 0.55, 95% CI: 0.35, 0.88; p = 0.012; n = 5). In subgroup analyses, the effect of low-GI diet interventions on premature birth was significant only in women with BMI higher than 30 kg/m2 (RR = 0.28, 95% CI: 0.10, 0.77, p = 0.014; n = 3); the significant effect on GWG was not altered by stratification of BMI and the type of GDM risk factors. No significant changes in other maternal and newborn outcomes were found.

CONCLUSIONS

Low-GI diet advice interventions during pregnancy decreased GWG and the risk of premature birth in women with elevated GDM risk; however, the interventions did not significantly prevent GDM development in these women.

Dietary Patterns Associated with Abnormal Glucose Tolerance following Gestational Diabetes Mellitus: The MyNutritype Study

Abnormal glucose tolerance (AGT), which includes type 2 diabetes and pre-diabetes, is highly prevalent in women post gestational diabetes mellitus (post-GDM). Dietary patterns have been associated with the risk of developing AGT in women post-GDM, but evidence in Asian populations is sparse. This study aimed to determine the association between a posteriori dietary patterns and AGT in women post-GDM. This cross-sectional study recruited 157 women post-GDM (mean age 34.8 years) from Seri Kembangan Health Clinic and Universiti Putra Malaysia. AGT was diagnosed according to the Malaysian Clinical Practice Guidelines using a 75 g 2 h oral glucose tolerance test or HbA1c. Food intake was assessed using the 2014 Malaysian Adult Nutrition Survey food frequency questionnaire. Five dietary patterns were derived using principal component analysis: 'Unhealthy', 'Fish-eggs-fruits-vegetables', 'Cereals-confectionaries', 'Legumes-dairy', and 'Meat-sugar-sweetened-beverages'. After adjusting for sociodemographic characteristics and total energy intake, the 'Cereals-confectionaries' dietary pattern was significantly associated with AGT (adjusted odds ratio 1.536, p = 0.049). Targeted lifestyle modification, including dietary intervention, for women post-GDM is warranted to reduce their risk of AGT and its complications.

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.

Nutrient intakes of pregnant and lactating women in Indonesia and Malaysia: Systematic review and meta-analysis

Introduction

Optimizing dietary intake during pregnancy and lactation is crucial to the growth and development of children and their lifelong health. We performed a systematic review and meta-analysis to describe the nutrient intakes of pregnant and lactating women in Indonesia and Malaysia, countries that are experiencing rapid nutrition transition in Southeast Asia.

Methods

We screened 2,258 studies published between January 1980 and March 2021. The nutrient intakes of pregnant and lactating women were quantitatively analyzed to calculate the percentage of adequacy using national recommended daily allowances or nutrient intakes (RDA/RNI) and estimated average requirements (EAR) for micronutrients. Standardized mean differences (SMD) between dietary intake and RDA/RNI were determined for selected nutrients.

Results

Fifty-three studies were included and showed that energy and macronutrient intakes among pregnant and lactating women in both countries were below the RDA/RNI. In addition, most studies reported that women failed to meet the EAR for vitamin D (&lt;70% EAR), vitamin E (&lt;50% EAR), and water-soluble vitamins (&lt;80% EAR) except for vitamin C and A among Malaysians. Moreover, calcium, potassium, and iron intakes of pregnant women were &lt;60% EAR in Indonesia and &lt;80% EAR in Malaysia. Phosphorus intake among pregnant women in both countries and sodium intake among Malaysian pregnant women exceeded 100% EAR. Indonesian lactating women had &lt;60% EAR for calcium and potassium intakes, while Malaysian women had more than 100% EAR. For 21 studies reporting overall protein intakes, the standard mean difference (SMD) was −2.26 (95% CI; −2.98, −1.54) below the RDA/RNI for pregnant women and −0.67 SMD (95% CI −15.7, −11.5) for lactating women. When the four studies from Malaysia were analyzed separately, protein intakes of pregnant women were above the RNI. Moreover, low intakes of vitamin D, vitamin C, calcium, and iron, but sufficient intakes in vitamin A, zinc, and phosphorus were observed in pregnant women in both countries.

Conclusion

Dietary intakes of energy, macronutrients, and micronutrients (vitamin D, vitamin E, water-soluble vitamins, calcium, and iron) of pregnant and lactating women in Indonesia and Malaysia were below the recommendations. Important heterogeneities were observed even between these two countries for specific essential nutrient intakes. Innovative research and targeted programs to address specific deficiencies should be prioritized.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021252204, identifier: CRD42021252204.

Self-care educational guide for mothers with gestational diabetes mellitus: A systematic review on identifying self-care domains, approaches, and their effectiveness

Background

Gestational Diabetes Mellitus (GDM) is a common form of poor carbohydrate intolerance, prevalent among pregnant women and associated with unhealthy lifestyle behaviors. Given the dearth of information on self-empowerment among mothers with GDM, a self-care health education package needs to be developed to prevent related complications.

Objective

This review aimed to identify self-care approaches, domains, and their effectiveness for a proper self-care educational guide package for women with GDM.

Design

A systematic review using electronic literature databases published between January 2016 and December 2022 was conducted.

Data Sources

Web of Science, Scopus, and Ovid databases were used.

Review Methods

This review utilized the PICO (Population, Intervention, Comparison, and Outcomes) framework to screen the retrieved articles for eligibility in which mothers with GDM, educational materials, standard practice or intervention, and effectiveness were considered the PICO, respectively. The CIPP (Context, Input, Process, Product) model served as a framework for adopting the education development model. Mixed methods appraisal tool was used for quality assessment. Data extraction and synthesis without meta-analysis were presented as evidence tables.

Results

A total of 19 articles on GDM were included in the final analysis (16 Intervention studies, two qualitative studies, and one mixed-methods study). Four broad domains emerged from the analysis: 1) information or knowledge of GDM, 2) monitoring of blood glucose levels, 3) practice of healthy lifestyles, and 4) other non-specific activities. The majority of the articles employed a face-to-face approach in executing the educational group sessions, and most studies disclosed their positive effects on GDM management. Other methods of evaluating intervention effectiveness were described as improved self-care behavior, increased satisfaction score, enhanced self-efficacy, good glucose control, and better pregnancy outcome.

Conclusion

Knowledge or information about GDM, healthy diet, and exercise or physical activity was found to be the most applied domains of intervention. Framework domains based on the present review can be used in the future development of any interventional program for GDM women in enhancing health information reaching the targeted group in promoting self-efficacy.

PROSPERO registration number

CRD42021229610.

Carbohydrate intake quality and gestational diabetes mellitus, and the modifying effect of air pollution

Background

Nutritional management is the cornerstone of gestational diabetes mellitus (GDM) prevention. High quality instead of low quantity of carbohydrate intake has been paying attention in controlling glycemia. Air pollution exposure can be interacted with dietary sourced nutrients, which may modify the associations with GDM. This study aims to explore the associations between overall quality of carbohydrate intake and GDM as well as the modifying effect of prenatal air pollution exposure.

Methods

Carbohydrate quality index (CQI) was calculated was calculated by summing scores of the four components; Land use regression prediction models were used to assess the air pollution exposure levels. GDM definition was based on 75 g glucose tolerance test results. Associations between pre-pregnancy CQI, pre-natal air pollution as well as the modifying effect on GDM were explored based on a birth cohort in China.

Results

A total of 3,183 participants were included, of which 784 (24.63%) were diagnosed with GDM. Higher pre-pregnancy CQI was associated with a lower incidence of GDM [odds ratio (OR) = 0.75, 95% confidence interval (CI): 0.56-0.99, P _{for trend} = 0.04], especially for higher fasting blood glucose related GDM (OR = 0.66, 95% CI: 0.47, 0.91). Higher air pollution exposure before and during pregnancy was associated with a greater risk of GDM. Higher exposure to particulate matter with an aerodynamic diameter of < 2.5 μm (P _{for interaction} < 0.01), particulate matter with an aerodynamic diameter of < 10 μm (P _{for interaction} < 0.01), and sulfur dioxide (P _{for interaction} = 0.02) during pregnancy decreased the beneficial effect of high pre-pregnancy CQI on GDM.

Conclusion

CQI related dietary interventions pre-pregnancy to prevent GDM incidence should be considered. Women who are planning to be pregnant should avoid high exposure to air pollution during pregnancy.

Endocrine-disrupting chemicals and the risk of gestational diabetes mellitus: a systematic review and meta-analysis

OBJECTIVE

To conduct a comprehensive systematic review and meta-analysis to estimate the relationship between endocrine-disrupting chemicals (EDCs), including polychlorinated biphenyls (PCBs), poly-brominated diphenyl ethers (PBDEs), phthalates (PAEs), and per- and polyfluoroalkyl substances (PFAS) exposure and risk of gestational diabetes mellitus (GDM).

METHODS

Relevant studies from their inception to November 2021 were identified by searching EMBASE, PubMed, and Web of Science. The cohort and case-control studies that reported effect size with 95% confidence intervals (CIs) of EDC exposure and GDM were selected. The heterogeneity among the included studies was quantified by I² statistic. Publication bias was evaluated through the Begg and Egger tests.

RESULTS

Twenty-five articles with a total of 23,796 participants were found. Results indicated that exposure to PCBs has a significant influence on the incidence of GDM (OR = 1.14; 95% CI = 1.00--1.31; n = 8). The risk of GDM was found to be associated with PBDE exposure (OR = 1.32; 95% CI = 1.15-1.53; n = 4). PAEs and PFASs exposure were also positively associated with the risk of GDM, with summary ORs of 1.10 (95% CI = 1.03-1.16; n = 7 for PAEs) and 1.09 (95% CI = 1.02-1.16; n = 11 for PFASs), respectively. When only cohort studies were considered, the summary OR between PCBs exposure and the risk of GDM was 0.99 (95% CI = 0.91-1.09; n = 5). Meanwhile, the summary ORs from cohort studies for PBDEs, PAEs, and PFASs exposure were 1.12 (95% CI = 1.00-1.26; n = 2), 1.08 (95% CI = 1.02-1.15; n = 5), and 1.06 (95% CI = 1.00-1.12; n = 8), respectively. The Beggs and Egger tests did not show publication bias, and the sensitivity analyses did not change the results in this meta-analysis.

CONCLUSION

These results support that exposure to certain EDCs, including PCBs, PBDEs, PAEs, and PFAS, increase the risk of GDM. Further large-sample epidemiologic researches and mechanistic studies are needed to verify the potential relationship and biological mechanisms. These results are of public health significance because the daily EDC exposure is expected to increase the risk of GDM development.

Specific fruit but not total fruit intake during early pregnancy is inversely associated with gestational diabetes mellitus risk: a prospective cohort study

OBJECTIVES

Fruit intake may influence gestational diabetes mellitus (GDM) risk. However, prospective evidence remains controversial and limited. The current study aimed to investigate whether total fruit and specific fruit intake influence GDM risk.

DESIGN

A prospective cohort study was conducted. Dietary information was collected by a 3-d 24-h dietary recall. All participants underwent a standard 75-g oral glucose tolerance test at 24-28 gestational weeks. Log-binomial models were used to estimate the association between fruit intake and GDM risk, and the results are presented as relative risks (RR) and 95 % CI.

SETTING

Southwest China.

PARTICIPANTS

Totally, 1453 healthy pregnant women in 2017.

RESULTS

Total fruit intake was not associated with lower GDM risk (RR of 1·03 (95 % CI 0·83, 1·27) (Ptrend = 0·789)). The RR of GDM risk was 0·73 for the highest anthocyanin-rich fruit intake quartile compared with the lowest quartile (95 % CI 0·56, 0·93; Ptrend = 0·015). A higher grape intake had a linear inverse association with GDM risk (Q4 v. Q1: RR = 0·65; 95 % CI 0·43, 0·98; Ptrend = 0·044), and after further adjustment for anthocyanin intake, the inverse association tended to be non-linear (Q4 v. Q1: RR = 0·65; 95 % CI 0·44, 0·98; Ptrend = 0·079). However, we did not find an association between glycaemic index-grouped fruit, glycaemic load-grouped fruit or other fruit subtype intake and GDM risk.

CONCLUSIONS

In conclusion, specific fruit intake (particularly anthocyanin-rich fruit and grapes) but not total fruit intake was inversely associated with GDM risk.

Prevention of Gestational Diabetes: The Role of Dietary Intake, Physical Activity, and Weight before, during, and between Pregnancies

Gestational diabetes mellitus (GDM) is the most common complication of pregnancy and a significant clinical and public health problem with lifelong and intergenerational adverse health consequences for mothers and their offspring. The preconception, early pregnancy, and interconception periods represent opportune windows to engage women in preventive and health promotion interventions. This review provides an overview of findings from observational and intervention studies on the role of diet, physical activity, and weight (change) during these periods in the primary prevention of GDM. Current evidence suggests that supporting women to increase physical activity and achieve appropriate weight gain during early pregnancy and enabling women to optimize their weight and health behaviors prior to and between pregnancies have the potential to reduce rates of GDM. Translation of current evidence into practice requires further development and evaluation of co-designed interventions across community, health service, and policy levels to determine how women can be reached and supported to optimize their health behaviors before, during, and between pregnancies to reduce GDM risk.

Associations of urinary phenolic environmental estrogens exposure with blood glucose levels and gestational diabetes mellitus in Chinese pregnant women

BACKGROUND

Endocrine-disrupting chemicals (EDCs) are considered to be related to diabetes, but studies of the association between phenolic EDCs and gestational diabetes mellitus (GDM) are limited.

OBJECTIVES

To assess associations of maternal urinary bisphenol A (BPA), nonylphenol (NP), and 2-tert-octylphenol (2-t-OP) with GDM occurrence.

METHODS

A cross-sectional study was performed among 390 Chinese women at 24-28 weeks of gestation. GDM was diagnosed with a 2-h 75-g oral glucose tolerance test (OGTT). BPA, NP, and 2-t-OP concentrations were determined in urine samples. Linear and logistic regression tests evaluated associations of BPA, NP, and 2-t-OP with blood glucose levels and GDM prevalence.

RESULTS

The 2-t-OP concentrations in GDM patients were significantly higher than in non-GDM women with median values of 2.23 μg/g Cr and 1.79 μg/g Cr, respectively. No significant difference was observed in BPA and NP. Urinary 2-t-OP was positively associated with blood glucose levels after adjustment for several confounding factors and urinary BPA and NP. Higher 2-t-OP levels were associated with higher odds of GDM (OR: 5.78; 95% CI: 2.04, 16.37), whereas higher NP levels were associated with lower odds (OR: 0.22; 95% CI: 0.05, 0.85) in the adjusted models. In addition, compared to the first quartile of 2-t-OP, the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for GDM in the second, third, and fourth quartiles were 2.81 (1.23, 6.42), 3.01 (1.30, 6.93), and 5.49 (2.24, 13.46), respectively.

CONCLUSION

Our study indicates that, for the first time to our knowledge, exposure to 2-t-OP is associated with a higher risk of GDM. However, higher NP exposure is associated with lower GDM risk. Further studies are necessary to affirm the associations of 2-t-OP and NP with GDM, and to elucidate the causality of these findings.

The association between dietary glycemic index and load and risk of gestational diabetes mellitus: A prospective study

AIMS

This study aimed to investigate the association between dietary GI and GL and risk of GDM in a group of pregnant women in Iran.

METHODS

A number of 812 pregnant women were recruited in their first trimester in a prospective study. A validated 117-item semi-quantitative food frequency questionnaire was used to assess usual dietary intakes of participants at study baseline. Dietary GI and GL were calculated based on earlier publications. GDM was diagnosed based on the results of a fasting plasma glucose concentration and a 50-g, 1-h oral glucose tolerance test at 24-28 weeks of gestation. Cox proportional hazards model was used to compute relative risks (RRs) and 95% confidence intervals (CI) for GDM.

RESULTS

Mean ± SD of age and BMI of study participants was 29.4 ± 4.84 y and 25.14 ± 4.08 kg/m², respectively at study baseline. Mean ± SD of dietary GI was 58 ± 7 and that of dietary GL was 176 ± 42. Overall, 28.4% (n = 231) of study population developed GDM at weeks 24-28 of pregnancy. After adjustment for potential confounding variables, we found that women in the highest tertile of dietary GL were 43% more likely to develop GDM than those in the lowest tertile (95% CI: 1.01, 2.00; P-trend = 0.03). However, no significant association was seen between dietary GI (RR for the highest tertile compared to the lowest: 0.85; 95% CI: 0.61, 1.20; P-trend = 0.37), and risk of GDM.

CONCLUSIONS

We found that women with the highest dietary GL were at a greater risk of developing GDM during pregnancy. No significant association was seen between dietary GI and risk of GDM.