The effect of high dietary fiber intake on gestational weight gain, fat accrual, and postpartum weight retention: a randomized clinical trial

A high fiber diet intervention during pregnancy: The SPROUT (Single goal in PRegnancy to optimize OUTcomes) protocol paper

BACKGROUND

Interventions to prevent excessive gestational weight gain (GWG) have had a limited impact on maternal and infant outcomes. Dietary fiber is a nutrient with benefits that counters many of the metabolic and inflammatory changes that occur during pregnancy. We will determine if a high dietary fiber (HFib) intervention provides benefit to maternal and infant outcomes.

METHODS AND DESIGN

Pregnant women will be enrolled in an 18-week intervention and randomized in groups of 6-10 women/group into the intervention or control group. Weekly lessons will include information on high-dietary fiber foods and behavior change strategies. Women in the intervention group will be given daily snacks high in dietary fiber (10-12 g/day) to facilitate increasing dietary fiber intake. The primary aim will assess between-group differences for the change in maternal weight, dietary fiber intake, dietary quality, and body composition during pregnancy and up to two months post-partum. The secondary aim will assess between-group differences for the change in maternal weight, dietary fiber intake, and dietary quality from two months to one year post-partum and infant body composition from birth to one-year-old.

DISCUSSION

Effective and simple intervention strategies to improve maternal and offspring outcomes are lacking. Changes during the perinatal period are related to the risk of disease development in the mother and offspring. However, it is unknown which changes can be successfully targeted to have a meaningful impact. We will test the effect of an intervention designed to counter many of the metabolic and inflammatory changes that occur during pregnancy.

ETHICS AND DISSEMINATION

The University of Kansas Medical Center Institutional Review Board (IRB) approved the study protocol (STUDY00145397). The results of the trial will be disseminated at conferences and in peer reviewed publications.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT04868110.

Pregnancy-specific dietary guidelines for Americans are not met: Findings from a pilot study

Objective

To assess maternal dietary intake during pregnancy and adherence to the 2020-2025 pregnancy-specific Dietary Guidelines for Americans (DGA).

Methods

This was a retrospective observational study. The study population consisted of women who gave birth to term infants (>37 weeks of gestation). Participants were given the Dietary Screener Questionnaire (DSQ) after birth and asked to recall their dietary intake in the last month of pregnancy. Participants' estimated dietary intakes were then compared to the 2020-2025 DGA which includes specific recommendations for pregnant women.

Results

Out of 51 women who completed the DSQ, none consumed the recommended amounts of all surveyed dietary factors. Specifically, only one woman (2%) met the recommended intake of fruits, 11 women (22%) met the recommended intake of calcium, 25 women (49%) exceeded the recommended upper limit for added sugar intake, and none of the women (0%) met the intake of vegetables, whole grains, dairy and fiber.

Conclusion

Women in our study did not adhere to the pregnancy-specific DGA recommendations in the last month of pregnancy. Our findings underscore the need to increase maternal nutritional awareness and education to improve adherence to the DGA.

Exploring the Role of Mediterranean and Westernized Diets and Their Main Nutrients in the Modulation of Oxidative Stress in the Placenta: A Narrative Review

Oxidative stress is a major cellular event that occurs in the placenta, fulfilling critical physiological roles in non-pathological pregnancies. However, exacerbated oxidative stress is a pivotal feature of different obstetric complications, like pre-eclampsia, fetal growth restriction, and other diseases. Compelling evidence supports the relevant role of diet during pregnancy, with pleiotropic consequences for maternal well-being. The present review aims to examine the complex background between oxidative stress and placental development and function in physiological conditions, also intending to understand the relationship between different dietary patterns and the human placenta, particularly how this could influence oxidative stress processes. The effects of Westernized diets (WDs) and high-fat diets (HFDs) rich in ultra-processed foods and different additives are compared with healthy patterns such as a Mediterranean diet (MedDiet) abundant in omega 3 polyunsaturated fatty acids, monounsaturated fatty acids, polyphenols, dietary fiber, and vitamins. Although multiple studies have focused on the role of specific nutrients, mostly in animal models and in vitro, further observational and intervention studies focusing on the placental structure and function in women with different dietary patterns should be conducted to understand the precise influence of diet on this organ.

The association of intrauterine and postnatal growth patterns and nutritional status with toddler body composition

BACKGROUND

Growth patterns may be indicative of underlying changes in body composition. However, few studies have assessed the association of growth and body composition in poorly resourced regions experiencing the double-burden of malnutrition exists. Thus, the aims of this study were to investigate the association of intrauterine and postnatal growth patterns with infant body composition at 2 years in a middle-income country.

METHODS

Participants were from the International Atomic Energy Agency Multicentre Body Composition Reference study. Fat mass (FM), fat free mass (FFM), Fat mass index (FMI), fat free mass index (FFMI), and percentage fat mass (%FM) were measured in 113 infants (56 boys and 57 girls), from Soweto, South Africa, using deuterium dilution from 3 to 24 months. Birthweight categories were classified using the INTERGROWTH-21 standards as small (SGA), appropriate (AGA), and large-for gestational age (LGA). Stunting (> -2 SDS) was defined using the WHO child growth standards. Birthweight z-score, conditional relative weight and conditional length at 12 and 24 mo were regressed on body composition at 24 mo.

RESULTS

There were no sex differences in FM, FFM, FMI and FFMI between 3 and 24 mo. SGA and AGA both had significantly higher %FM than LGA at 12 mo. LGA had higher FM at 24 mo. Children with stunting had lower FM (Mean = 1.94, 95% CI; 1.63-2.31) and FFM (Mean = 5.91, 95% CI; 5.58-6.26) at 12 mo than non-stunting, while the reverse was true for FFMI (Mean = 13.3, 95% CI; 12.5-14.2) at 6 mo. Birthweight and conditionals explained over 70% of the variance in FM. CRW at both 12 and 24 mo was positively associated with FM and FMI. CRW at 12 mo was also positively associated with FMI, while CH at 24 mo was negatively associated with both FFMI and FMI in boys.

CONCLUSION

Both LGA and SGA were associated with higher body fat suggesting that both are disadvantaged nutritional states, likely to increase the risk of obesity. Growth patterns through infancy and toddler period (1-2 years) are indicative of body fat, while growth patterns beyond infancy are less indicative of fat-free mass.

Maternal Bean Consumption during Pregnancy: Distribution and Nutritional Outcomes

(1) Background: Due to their high nutritional value, we aimed to characterize the frequency and amount of maternal consumption of beans during pregnancy and their associations with diet quality and nutrient intake. (2) Methods: We conducted a secondary data analysis of US pregnant women (n = 1444) from the Infant Feeding Practices Study II, a longitudinal study that followed mother-infant pairs from late pregnancy to 1 year postpartum. Maternal bean intake (food types [dried beans, chili, and bean soup], frequency, serving size, and amount), diet quality (Healthy Eating Index [HEI]), and nutrient intake were estimated with a Food Frequency Questionnaire taken in the third trimester of pregnancy. Associations of bean consumption with diet quality and nutrient intake were examined with analysis of variance, Fisher's least significant difference tests, correlation coefficients, and coefficients of determination. (3) Results: In general, maternal bean consumption was low during pregnancy: 0.31 cups/week of dried beans, 0.37 cups/week of chili, and 0.10 cups/week of bean soup. Maternal bean consumption varied by socio-demographics and geographic regions. In comparison with those who never consumed dried beans, mothers who ate dried beans ≥ 1 time per week had a higher mean HEI score (67.5 vs. 63.6), intake of total fiber (24.4 vs. 17.4 g/day), and protein (93.4 vs. 79.9 g/day), but a lower percentage of energy from added sugar (12.6 vs. 15.2%). Higher dried bean consumption had weak-to-moderate correlations with intake of total fiber (correlation coefficient, 0.320), insoluble fiber (0.316), soluble fiber (0.310), and folate (0.286). Similar but less extensive correlations were observed for chili and bean soup consumption. (4) Conclusions: In this US cohort of pregnant women, bean consumption was low. Increased intake of beans (≥1 time per week) may improve maternal diet quality during pregnancy.

Maternal Diet Quality During Pregnancy and Offspring Hepatic Fat in Early Childhood: The Healthy Start Study

BACKGROUND

Overnutrition in utero may increase offspring risk of nonalcoholic fatty liver disease (NAFLD), but the specific contribution of maternal diet quality during pregnancy to this association remains understudied in humans.

OBJECTIVES

This study aimed to examine the associations of maternal diet quality during pregnancy with offspring hepatic fat in early childhood (median: 5 y old, range: 4-8 y old).

METHODS

Data were from 278 mother-child pairs in the longitudinal, Colorado-based Healthy Start Study. Multiple 24-h recalls were collected from mothers during pregnancy on a monthly basis (median: 3 recalls, range: 1-8 recalls starting after enrollment), and used to estimate maternal usual nutrient intakes and dietary pattern scores [Healthy Eating Index-2010 (HEI-2010), Dietary Inflammatory Index (DII), and Relative Mediterranean Diet Score (rMED)]. Offspring hepatic fat was measured in early childhood by MRI. Associations of maternal dietary predictors during pregnancy with offspring log-transformed hepatic fat were assessed using linear regression models adjusted for offspring demographics, maternal/perinatal confounders, and maternal total energy intake.

RESULTS

Higher maternal fiber intake and rMED scores during pregnancy were associated with lower offspring hepatic fat in early childhood in fully adjusted models [Back-transformed β (95% CI): 0.82 (0.72, 0.94) per 5 g/1000 kcal fiber; 0.93 (0.88, 0.99) per 1 SD for rMED]. In contrast, higher maternal total sugar and added sugar intakes, and DII scores were associated with higher offspring hepatic fat [Back-transformed β (95% CI): 1.18 (1.05, 1.32) per 5% kcal/d added sugar; 1.08 (0.99, 1.18) per 1 SD for DII]. Analyses of dietary pattern subcomponents also revealed that lower maternal intakes of green vegetables and legumes and higher intake of "empty calories" were associated with higher offspring hepatic fat in early childhood.

CONCLUSIONS

Poorer maternal diet quality during pregnancy was associated with greater offspring susceptibility to hepatic fat in early childhood. Our findings provide insights into potential perinatal targets for the primordial prevention of pediatric NAFLD.

Modelling the impact of diet and physical activity on body mass index in pre-pregnant and postpartum women

OBJECTIVES

This study aimed to assess, using simulation modeling, the theoretical effect of key diet and physical activity (PA) modification scenarios could have on body mass index (BMI) in prepregnant and postpartum women.

METHODS

Simulation modeling using data from the 2011 to 2012 National Nutrition and Physical Activity Survey was performed for a subsample of prepregnant and postpartum women. The regression coefficients for each diet and PA component from multivariable linear regression equations for BMI were used to calculate a predicted BMI. Scenario modeling using a moderation approach was applied to targeted diet and PA components for the entire sample and subgroups of populations of women who failed to meet dietary and PA recommendations and among the lowest socioeconomic groups.

RESULTS

In prepregnancy and postpartum scenarios, respectively, increasing whole grains by 2 to 3 servings/d reduced BMI by 1.16 and 0.85 kg/m². For postpartum women, BMI was reduced by 0.28 kg/m² for every 5-g/d increase in fiber intake. A 480- and 540-min/wk increase in PA resulted in average BMI reductions of 0.95 and 1.19 kg/m² in prepregnant and postpartum women, respectively. A similar pattern of theoretical reductions in BMI was observed with increased whole grains, fiber, and PA among the most disadvantaged socioeconomic groups of women.

CONCLUSIONS

Increasing intake of whole grains by 2 to 3 servings/d could result in reductions in BMI of 1.16 and 0.85 kg/m², and a 480- and 540-min/wk increase in PA could result in BMI reduction of 0.95 and 1.19 kg/m² in prepregnant and postpartum women, respectively. This provides an evidence base to guide tailored nutrition messaging for obesity prevention efforts in reproductive age women.

Association of plant-based dietary patterns in first trimester of pregnancy with gestational weight gain: results from a prospective birth cohort

BACKGROUND/OBJECTIVES

Plant-based dietary patterns are becoming more popular worldwide. We aimed to examine the relationship between plant-based dietary patterns and the risk of inadequate or excessive gestational weight gain (GWG) in Iranian pregnant women.

METHODS

We prospectively followed 657 pregnant women in Iran. Adherence to the plant-based diet, represented by plant-based (PDI), healthy (hPDI) and unhealthy plant-based (uPDI) dietary indexes was evaluated by applying a 90-item food frequency questionnaire during the first trimester of pregnancy. Multivariable-adjusted Cox proportional-hazards regression model was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) across quartiles of plant-based diet scores.

RESULTS

Over 25,562 person-weeks of follow-up, we documented 106 and 294 participants with inadequate and excessive GWG, respectively. We found a strong inverse association between adherence to the PDI and inadequate GWG after adjustment for demographic and confounding variables. Women in the highest quartile of the PDI had 50% lower risk of inadequate GWG than those in the lowest quartile (adjusted HR: 0.50; 95%CI 0.29, 0.89; P = 0.02). No significant association was found between hPDI and uPDI and inadequate GWG. There was no association between PDI, hPDI, and uPDI and the risk of excessive GWG.

CONCLUSIONS

Greater adherence to a plant-based diet during the first trimester of pregnancy may be associated with a lower risk of inadequate GWG. This finding needs to be confirmed in larger cohort studies, considering other pregnancy outcomes such as birth weight and the potential changes across the trimester in terms of food types and quantity.

Association of Dietary Intake of Polyphenols with an Adequate Nutritional Profile in Postpartum Women from Argentina

HJ-Biplot analysis is a multivariate graphic representation that collects data covariation structure between variables and individuals to represent them in a low-dimensional space with the highest quality in the same reference system. Consequently, it is a promising technique for evaluating dietary exposure to polyphenols and accurately characterizing female nutrition. Herein, we hypothesized that polyphenol intake defines specific clusters with dietary impacts, which can be assessed using HJ-Biplot, based on a cross-sectional study in Argentina. The study included 275 healthy postpartum women who provided information about their food frequency intake and other conditions, which were then used to evaluate polyphenolic intake using the Phenol-Explorer database. Outcomes were established using HJ-Biplot for clustering and ANOVA to compare their impact on diet quality indicators. Two HJ-Biplot models were run (for intakes >20 mg/d and 5∼20 mg/d, respectively) to identify three clusters per model with excellent statistical fitness to explain the data. Thus, specific polyphenolic clusters with potentially bioactive and safe compounds were defined despite significant interindividual variability. In fact, women with the lowest polyphenolic intake exhibited worse dietary quality, body fat, and physical activity. As a result, HJ-Biplot proved to be an effective technique for clustering women based on their dietary intake of these compounds. Furthermore, cluster membership improved the intake of antioxidants, water, fiber, and healthy fats. Additionally, women with formal jobs and a higher educational level showed a better diet. Dietary polyphenols are critical during postpartum because they exert beneficial effects on women and breastfed infants.

Maternal Long-Term Intake of Inulin Improves Fetal Development through Gut Microbiota and Related Metabolites in a Rat Model

Adequate dietary fiber intake during gestation is critical for maternal-fetal health. This experiment aims to uncover the impacts of maternal long-term intake of inulin on fetal development and its underlying mechanism. Eighty female Sprague-Dawley rats were randomly assigned to two groups receiving either a fiber-free diet or an inulin diet (inulin) for three parities. On the 19^th day of pregnancy in the third parity, blood, intestinal, placental, and colonic digesta samples were collected. Results showed that maternal intake of inulin significantly decreased the within-litter birth weight variation in parities 2 and 3. Inulin intake modified the gut microbiome profiles and elevated the colonic contents of short chain fatty acids (propionate and butyrate). Inulin decreased the serotonin (5-HT) concentration in the colon, whereas it increased the 5-HT concentrations in serum and placenta and the number of 5-HT⁺ enterochromaffin cells in the colon. The protein expression of melatonin-synthesizing enzyme (arylalkylamine N-acetyltransferase) and the melatonin concentration in the placenta were also increased by inulin. Inulin improved the placental redox status and nutrient transport. These findings indicated that maternal long-term intake of inulin improves fetal development by altering the intestinal microbiota and related metabolites in rats.

Association of weight status and carbohydrate intake with gestational weight gain

Test the hypothesis that women with obesity have greater gestation weight gain (GWG) with a moderately higher, vs lower, carbohydrate (CHO) diet, independent of energy intake, whereas GWG for women of normal weight would not differ by CHO group. This was a secondary analysis of data collected from glucose tolerant women with normal weight (NW) or obesity in pregnancy. Women completed a three-day food diary 16 to 20 weeks. A median split for percent kilocalories from CHO (median = 49.6%) categorized women into moderately highCHO vs lowCHO groups (n = 13-15/group). GWG was calculated between consent and the last prenatal care visit. A two-way ANOVA was used to examine whether there was an interaction between weight status and CHO group on GWG, independent of energy intake, time between consent and last prenatal visit, and age. Women in both highCHO groups consumed more sugars and starches compared to women in the lowCHO groups (P < .05). A significant interaction between weight status and CHO content of the diet was found (P < .05), such that, for women with obesity, those consuming a lowCHO diet had less GWG than those consuming a highCHO diet, whereas the pattern was opposite for women with NW. Results suggest that intake of a moderately lower CHO diet may help limit GWG among glucose tolerant women with obesity. Given that women in this study were eligible only if they had normal fasting glucose concentrations in early pregnancy, it is not clear if these results would generalize to all women with obesity during pregnancy.

Dietary Blueberry and Soluble Fiber Supplementation Reduces Risk of Gestational Diabetes in Women with Obesity in a Randomized Controlled Trial

BACKGROUND

Gestational diabetes mellitus (GDM) is a growing public health concern and maternal obesity and poor dietary intakes could be implicated. Dietary polyphenols and fiber mitigate the risk of diabetes and its complications, but little is known about their efficacy in preventing GDM.

OBJECTIVES

We examined the effects of whole blueberry and soluble fiber supplementation on primary outcomes of cardiometabolic profiles in women at high risk of developing GDM.

METHODS

Women (n = 34; mean ± SD age: 27 ± 5 y; BMI: 35.5 ± 4.0 kg/m2; previous history of GDM ∼56%; Hispanic ∼79%) were recruited in early pregnancy (<20 weeks of gestation) and randomly assigned to 1 of the following 2 groups for 18 wk: intervention (280 g whole blueberries and 12 g soluble fiber per day) and standard prenatal care (control). Both groups received nutrition education and maintained 24-h food recalls throughout the study. Data on anthropometrics, blood pressure, and blood samples for biochemical analyses were collected at baseline (<20 weeks), midpoint (24-28 weeks), and end (32-36 weeks) of gestation. Diagnosis of GDM was based on a 2-step glucose challenge test (GCT). Data were analyzed using a mixed-model ANOVA.

RESULTS

Maternal weight gain was significantly lower in the dietary intervention than in the control group at the end of the trial (mean ± SD: 6.8 ± 3.2 kg compared with 12.0 ± 4.1 kg, P = 0.001). C-reactive protein was also lower in the intervention than in the control group (baseline: 6.1 ± 4.0 compared with 6.8 ± 7.2 mg/L; midpoint: 6.1 ± 3.7 compared with 7.5 ± 7.3 mg/L; end: 5.5 ± 2.2 compared with 9.5 ± 6.6 mg/L, respectively, P = 0.002). Blood glucose based on GCT was lower in the intervention than in the control (100 ± 33 mg/dL compared with 131 ± 40 mg/dL, P < 0.05). Conventional lipids (total, LDL, and HDL cholesterol and triglycerides) did not differ between groups over time. No differences were noted in infant birth weight.

CONCLUSIONS

Whole blueberry and soluble fiber supplementation may prevent excess gestational weight gain and improve glycemic control and inflammation in women with obesity.This trial was registered at clinicaltrials.gov as NCT03467503.

High-Fiber Diet during Pregnancy Characterized by More Fruit and Vegetable Consumption

Higher dietary fiber intakes during pregnancy may have the potential health benefits of increasing gut microbiome diversity, lowering the risk of glucose intolerance and pre-eclampsia, achieving appropriate gestational weight gain, and preventing constipation. In this observational cohort study, we have assessed the dietary fiber intakes of 804 women in late pregnancy, using a semi-quantitative food frequency questionnaire (SQ-FFQ). Overall, the median (interquartile range) dietary fiber intake was 24.1 (19.0–29.7) grams per day (g/day). Only 237/804 (29.5%) women met the recommended Adequate Intake (AI) of dietary fiber during pregnancy of 28 g/day. Women consuming the highest quartile of fiber intakes (34.8 (IQR 32.1–39.5) g/day) consumed more fruit, especially apples and bananas, than women consuming the lowest quartile of fiber intakes (15.9 (IQR 14.4–17.5) g/day). These women in the highest fiber-intake quartile were older (p < 0.01), more had completed further education after secondary school (p = 0.04), and they also consumed more vegetables (67 g/day) compared to the women in the lowest fiber consumption quartile (17 g vegetables/day). Bread intakes of 39–42 g/day were consistent in quantities consumed across all four fiber-intake quartiles. Our findings suggest that antenatal education advice targeting increased fruit and vegetable consumption before and during pregnancy may be a simple strategy to achieve increased total dietary fiber intakes to reach recommended quantities.