Effect of Adherence to a Mediterranean Diet and Olive Oil Intake during Pregnancy on Risk of Small for Gestational Age Infants

The Role of the Mediterranean Diet in Assisted Reproduction: A Literature Review

The Mediterranean Diet, characterized by high consumption of plant-based foods, olive oil, moderate intake of fish and poultry, and low consumption of red meat and processed foods, has been suggested to improve assisted reproductive technology (ART) outcomes. This narrative review aimed to summarize and synthesize the evidence from observational studies on the associations between preconception adherence to the Mediterranean Diet and ART outcomes. PubMed/MEDLINE, Embase, ScienceDirect, Google Scholar, and Web of Science databases were searched to identify relevant studies. Seven observational studies (n = 2321 women undergoing ART) were included. Adherence to the Mediterranean Diet was assessed using food frequency questionnaires with 6-195 items. Three studies found that higher Mediterranean Diet scores were associated with improved clinical pregnancy rates (OR 1.4, 95% CI 1.0-1.9; RR 1.98, 95% CI 1.05-3.78) or live birth rates (RR 2.64, 95% CI 1.37-5.07). Two studies showed a positive effect on embryo yield (p = 0.028) and ovarian response. However, two studies reported no significant associations with ultimate ART success, and four studies found no effects on oocyte and embryo number or quality. The heterogeneity in study designs, Mediterranean Diet assessment methods, and ART protocols limited the strength of conclusions. Evidence for the effects of greater adherence to the Mediterranean Diet on ART outcomes is limited but promising. Future research should focus on conducting randomized controlled trials with standardized Mediterranean Diet assessment methods to establish causal relationships between Mediterranean Diet adherence and ART outcomes, and to elucidate potential mechanisms of action.

Association between the Maternal Mediterranean Diet and Perinatal Outcomes: A Systematic Review and Meta-Analysis

The Mediterranean diet is a global, well-known healthy dietary pattern. This review aims to synthesize the existing evidence on the relationship between the maternal Mediterranean diet during pregnancy and perinatal outcomes, including randomized controlled trials (RCTs) and cohort studies. PubMed, Web of Science, and the Cochrane Library were searched from inception to 10 March, 2023, supplemented by manual screening. A random-effect model was used to estimate pooled sizes with 95% confidence intervals (CIs) for specific outcomes of interest. Data from 5 RCTs and 18 cohort studies with 107,355 pregnant participants were synthesized. In RCTs, it was observed that the maternal Mediterranean diet significantly reduced the incidence of gestational diabetes mellitus [odds ratio (OR), 0.56; 95% CI: 0.34, 0.93], as well as small for gestational age (0.55; 95% CI: 0.35, 0.88). In cohort studies, the highest adherence score to the maternal Mediterranean diet was inversely associated with a lower risk of various adverse pregnancy outcomes, including gestational diabetes mellitus (OR, 0.82; 95% CI: 0.67, 1.00), pregnancy-induced hypertension (0.73; 95% CI: 0.60, 0.89), pre-eclampsia (0.77; 95% CI: 0.64, 0.93), preterm delivery (0.67; 95% CI: 0.49, 0.91), low birth weight (0.70; 95% CI: 0.64, 0.78), intrauterine growth restriction (0.46; 95% CI: 0.23, 0.91), and increased gestational age at delivery (weighted mean difference, 0.11 wk; 95% CI: 0.03, 0.20). Meta-regression analyses did not identify the adjustment for confounders and geographical location as predictive factors for heterogeneity. The results suggest that adherence to the Mediterranean diet during pregnancy appears to be beneficial for perinatal outcomes. Future, larger, and higher-quality RCTs and cohort studies are warranted to confirm the present findings. PROSPERO registration no.: CRD42023406317.

Knowledge and adherence to the Mediterranean diet in individuals practicing regular amatorial physical activity: a cross-sectional study conducted in the Metropolitan Area of Palermo, Italy

Introduction

Mediterranean Diet (MD) is a universal model of nutrition that prevents several metabolic, cardiovascular, and oncological diseases. Main objective of the present study was to analyze adherence and knowledge regarding MD principles in a sample of individuals practicing amatorial sports from the Metropolitan Area of Palermo.

Methods

A cross-sectional study was conducted in 10 Sports Centers, between October 2020 and September 2021, through a previously validated anonymous questionnaire structured in five sections including 74 items.

Results

Overall, 337 subjects answered to the questionnaire. Based on the multivariable analysis conducted, a higher knowledge score (KS) on MD principles was observed among individuals daily consuming vegetables (OR: 3.32; CI95%: 1.82-6.02) and in the ones more adherent to MD principles (OR: 10.15; CI95%:5.47-18.85). More in depth, using MEDAS score to analyze the adherence to MD, a significant lower adherence was observed among overweight/obese (OR: 0.57; CI95%:0.33-0.99) and among employed subjects (OR: 0.52; IC95%: 0.28-0.98); while, a higher adherence was highlighted among daily consumers of vegetables (OR: 2.52; CI95%:1.52-4.17), daily consumers of fruit (OR: 1.77; CI95%:1.08-2.90), and in individuals that have daily breakfast (OR: 4.29; CI95%:1.15-15.96).

Discussion

In accordance with the WHO Europe Gaining Health Campaign, Public Health Authorities should simplify accessibility to healthy food among general population, promoting principles and accessibility to MD.

Relationship between the Mediterranean Diet Score in Pregnancy and the Incidence of Asthma at 4 Years of Age: The Japan Environment and Children's Study

Several scoring methods for the Mediterranean diet, which is considered as a healthy diet, are available, but studies that have compared more than one of these scores are rare. In addition, the applicability of Mediterranean diet scoring has not been sufficiently examined outside of Mediterranean regions. We collected data on the Mediterranean diet during pregnancy and the incidence of type 1 allergies in offspring from the Japan Environment and Children's Study. Using multiple Mediterranean diet scoring methods, we analyzed the effect of adherence to the Mediterranean diet in pregnancy on the allergies of the offspring. Overall, 46,532 pairs of mothers and children were analyzed. In Japan, a high adherence to the Mediterranean diet during pregnancy was associated with a lower incidence of asthma in the offspring (odds ratio: 0.896, 95% confidence interval: 0.835, 0.962). Furthermore, we found that the selection of the Mediterranean diet scoring method and the setting of the reference value significantly altered the results. Our findings suggest that an appropriate selection of scoring methods and a reference value for food items are important to analyze the effects of adherence to the Mediterranean diet inside and outside of Mediterranean regions.

Olive oil consumption confers protective effects on maternal-fetal outcomes: A systematic review of the evidence

Because of the maternal diet's importance, numerous studies have examined the effects of olive oil on pregnancy outcomes. This study provides a systematic review that evaluates the evidence between olive oil consumption and maternal-fetal outcomes. We hypothesized that olive oil reduced the risk of adverse pregnancy complications. We searched Web of Science, Scopus, PubMed, and Biblioteca Virtual em Saúde electronic databases (October and November 2021). The keywords used were pregnancy, olive oil, and pregnancy outcomes. This review included all the available studies in English and Portuguese. The exclusion criteria were (1) unrelated to olive oil consumption, (2) other outcomes, and (3) animal studies. The review included 9 articles (6 experimental and 3 observational). In the maternal outcome studies (n = 6), a higher olive oil consumption was associated with a lower prevalence of gestational diabetes mellitus, preeclampsia, and cardiovascular risk. In the fetal outcome studies (n = 8), olive oil consumption was associated with a lower risk for small- or large-for-gestational-age infants. Olive oil consumption confers protective effects on pregnancy outcomes; however, further studies are needed that are specifically designed for the impact of olive oil consumption on maternal-fetal outcomes.

Oleuropein Attenuates Oxidative Stress in Human Trophoblast Cells

Olive-derived bioactive compound oleuropein was evaluated against damage induced by hydrogen peroxide in human trophoblast cells in vitro, by examining the changes in several markers implicated in oxidative stress interactions in the placenta. Trophoblast HTR-8/SVneo cells were preincubated with OLE at 10 and 100 µM and exposed to H₂O₂, as a model of oxidative stress. Protein and lipid peroxidation, as well as antioxidant enzymes' activity, were determined spectrophotometrically, and DNA damage was evaluated by comet assay. iNOS protein expression was assessed by Western blot, while the mRNA expression of pro- and anti-apoptotic genes BAX and BCL2 and transcription factor NFE2L2, as well as cytokines IL-6 and TNF α were determined by qPCR. Oleuropein demonstrated cytoprotective effects against H₂O₂ in trophoblast cells by significantly improving the antioxidant status and preventing protein and lipid damage, as well as reducing the iNOS levels. OLE reduced the mRNA expression of IL-6 and TNF α, however, it did not influence the expression of NFE2L2 or the BAX/BCL2 ratio after H₂O₂ exposure. Oleuropein per se did not lead to any adverse effects in HTR-8/SVneo cells under the described conditions, confirming its safety in vitro. In conclusion, it significantly attenuated oxidative damage and restored antioxidant functioning, confirming its protective role in trophoblast.

New Validated Short Questionnaire for the Evaluation of the Adherence of Mediterranean Diet and Nutritional Sustainability in All Adult Population Groups

High adherence to a Mediterranean diet (MD) is favourable for its sustainability and beneficial effects on health. The available questionnaires, according to the MD dietary pattern, include the assessment of moderate alcohol consumption; but some groups, such as young adults and pre-conceptional and pregnant women, are not allowed to consume it. The aim of this study was to validate a new short questionnaire (MedQ-Sus) excluding alcohol consumption, to measure the adherence to the MD and to evaluate the nutritional adherence to a sustainable diet. The Harvard validated questionnaire was used for the validation study. A total of 316 subjects (20 to 70 YOA) completed both questionnaires. A high Spearman correlation coefficient (rho = 0.69; p < 0.01) was found between the MedQ-Sus and Harvard scores; a statistically significant positive correlation was found for all eight food groups. The MedQ-Sus had a significant discriminative capacity between adherence and non-adherence to the MD (optimal cut-off point = 9.5, sensitivity 0.86, specificity = 0.65). A very high nutritional adherence to a sustainable diet was found in the subjects for olive oil (97%), dairy food (90%), fresh vegetables (89%), fish and fish products (73), fresh fruit (56%), and cereals and cereals products (42%). A very low adherence was found for legumes (22%) and meat and meat products (9%). The results showed MedQ-Sus is a valid and quick assessment instrument for the evaluation of the adherence to the MD in all population groups, and could also be useful to evaluate the nutritional sustainability of the diet.

Periconceptional Mediterranean diet during pregnancy on children's health

During pregnancy, rapid and subtle physiological changes are observed from conception to birth. Nutrition and other lifestyle factors before and during pregnancy have been shown in the literature to influence the health of both mother and child. A healthy and varied diet during pregnancy can provide adequate energy and nutrients for both the mother and the growing fetus. Current research focuses on the periconceptional phase, which includes the early processes of gametogenesis, embryogenesis and placentation. A variety of abnormalities and pregnancy-related problems occur during this period, including congenital defects, fetal loss, miscarriage and preterm birth. A varied and balanced diet during periconception is important to maintain fetal development and growth. To date, numerous studies have been conducted to investigate the effects of consuming different nutrients, foods or food groups during pregnancy on the health of mother and child. For example, the Mediterranean diet is considered as a balanced, nutrient-rich diet due to the low consumption of meat products and fatty foods and the high consumption of vegetables, cheese, olive oil, fish, shellfish and little meat. While many studies have been conducted in the literature to investigate the effects of a Mediterranean diet during pregnancy on fetal health, the results have been inconclusive. The aim of this article is to review the current literature on the Mediterranean diet during pregnancy.

Prenatal adherence to the Mediterranean diet decreases the risk of having a small-for-gestational-age baby, ECLIPSES study

There is little evidence regarding the role that consuming a Mediterranean diet (MedDiet) during pregnancy plays in foetal growth. We therefore examined the relationship between maternal MedDiet adherence during pregnancy and anthropometric measures and small-for-gestational-age (SGA) at birth in a Spanish population on the north-eastern Mediterranean coast of Spain. Prospective analysis involved 614 mother–newborn pairs from the ECLIPSES study. Diet during pregnancy was assessed using a validated food frequency questionnaire, and a relative MedDiet score (rMedDiet) was calculated. Neonatal information, including weight, length, head circumference and SGA (< 10th percentile) at birth, was recorded. Multivariable logistic regression analyses were performed. The mean rMedDiet score was 9.8 (SD 2.1), ranging from 5 to 16 points. In the sample, 45% of the women had low (≤ 9 points), 32% had medium (10–11 points), and 22% had high (≥ 12 points) adherence to the rMedDiet. There was no association between rMedDiet and birth weight, length, head circumference or anthropometric indices (weight/length ratio and ponderal index). Pregnant women with a high rMedDiet score had a lower risk of delivering a SGA baby for weight (high vs low, OR = 0.36; 95% CI 0.16–0.79) and head circumference (high vs low, OR = 0.39; 95% CI 0.18–0.86), and a nonsignificant decrease in risk of SGA for length (high vs low, OR = 0.57; 95% CI 0.28–1.17). In conclusion, closer adherence to the MedDiet during pregnancy may have beneficial effects on foetal growth.

Application of Mediterranean Diet in Cardiovascular Diseases and Type 2 Diabetes Mellitus: Motivations and Challenges

Objective: Cardiovascular disease (CVD) is the leading cause of disability and death in many countries. Together with CVD, Type 2 diabetes mellitus (T2DM) accounts for more than 80% of all premature non-communicable disease deaths. The protective effect of the Mediterranean diet (MedDiet) on CVD and its risk factors, including T2DM, has been a constant topic of interest. Notwithstanding, despite the large body of evidence, scientists are concerned about the challenges and difficulties of the application of MedDiet. This review aims to explore the motivations and challenges for using MedDiet in patients with CVD and T2DM. Design: An electronic search was conducted for articles about MedDiet published in PubMed, ScienceDirect, Scopus, and Web of Science up to December 2021, particularly on CVD and T2DM patients. From a total of 1536 studies, the final eligible set of 108 studies was selected. Study selection involved three iterations of filtering. Results: Motivation to apply MedDiet was driven by the importance of studying the entire food pattern rather than just one nutrient, the health benefits, and the distinct characteristics of MedDiet. Challenges of the application of MedDiet include lacking universal definition and scoring of MedDiet. Influences of nutritional transition that promote shifting of traditional diets to Westernized diets further complicate the adherence of MedDiet. The challenges also cover the research aspects, including ambiguous and inconsistent findings, the inexistence of positive results, limited evidence, and generalization in previous studies. The review revealed that most of the studies recommended that future studies are needed in terms of health benefits, describing the potential benefits of MedDiet, identifying the barriers, and mainly discussing the effect of MedDiet in different populations. Conclusions: In general, there is consistent and strong evidence that MedDiet is associated inversely with CVD risk factors and directly with glycemic control. MedDiet is the subject of active and diverse research despite the existing challenges. This review informs the health benefits conferred by this centuries-old dietary pattern and highlights MedDiet could possibly be revolutionary, practical, and non-invasive approach for the prevention and treatment CVD and T2DM.

Adherence to the Mediterranean Diet of Pregnant Women in Central South Africa: The NuEMI Study

Introduction:

The Mediterranean diet (MeD) has been shown to have significant health benefits for adults and children. A mother’s diet during pregnancy directly impacts the health of her offspring. This study aimed to investigate the adherence to the MeD of pregnant women attending antenatal care at a Regional Hospital in Bloemfontein, South Africa (SA).

Methods:

A cross-sectional study was conducted on a consecutive sample of 681 pregnant women who attended the antenatal clinic of a Regional Hospital in Bloemfontein. Socio-demographics included: age, highest level of education, household income, employment status, and income stability. Food group intake was assessed with a quantitative food frequency questionnaire. The adapted Mediterranean Diet Adherence Screener (MeDAS) consisted of 13 of the original 14 questions that measured intake of key food groups (score of ⩽7 poor, 8-9 moderate, ⩾10 good) (wine intake was excluded for pregnant women).

Results:

A total of 681 pregnant women with a median age of 31.8 years (IQR: 26.8-36.5 years) and a median gestational age of 32.0 weeks at the time of the interview participated in the study. The vast majority showed poor adherence to the MeD (99.6%), with only 0.4% (n = 3) having moderate adherence and 0% good adherence. The median adherence score was 5 points and the maximum 8 points. Of those with poor adherence, only 11.5% had tertiary education, 43.2% earned less than R 3000 (<201 USD) per month, 52.5% were unemployed, and 42.0% did not have a stable income in the past 6 months. Of the 3 participants with moderate adherence, all had grade 11 to 12 education, 2 out of the 3 earned more than R3000 (201 USD), one was unemployed, and 2 had a stable income over the past 6 months. Compared to those with an income ⩽ R3000 (⩽201 USD), those with an income above R3000 were significantly more likely to eat nuts (including peanuts) (2.0% vs 4.6%, P = .05), and adhere to sofrito (similar to tomato and onion relish) intake (9.2% vs 15.6%, P = .02). Compared to those who only had a primary education level up to grade 10 (n = 229), those who had a secondary education level or more (grade 11 and higher, n = 452) were significantly more likely to consume enough olive oil per day (1.3% vs 5.0%, P = .01), and to consume sofrito (6.6% vs 18.0%, P = .02).

Conclusion:

Pregnant participants showed poor adherence to the MeD. Although almost all women fell in the poor adherence group, secondary education contributed to consuming recommended amounts of olive oil and sofrito and higher income was associated with an adequate intake of nuts and sofrito. Based on the findings, we recommend the development of a contextualized MeDAS tool that includes foods that are typically eaten by most South Africans for similar MeD benefits.

Mediterranean Diet in Developmental Age: A Narrative Review of Current Evidences and Research Gaps

Numerous studies in recent decades have shown that Mediterranean diet (MD) can reduce the risk of developing obesity in pediatric patients. The current narrative review summarizes recent evidence regarding the impact of MD across the different stages of child development, starting from fetal development, analyzing breastfeeding and weaning, through childhood up to adolescence, highlighting the gaps in knowledge for each age group. A literature search covering evidence published between 1 January 2000 and 1 March 2022 and concerning children only was conducted using multiple keywords and standardized terminology in PubMed database. A lack of scientific evidence about MD adherence concerns the age group undergoing weaning, thus between 6 months and one year of life. In the other age groups, adherence to MD and its beneficial effects in terms of obesity prevention has been extensively investigated, however, there are still few studies that correlate this dietary style with the incidence of non-communicable diseases. Furthermore, research on multi-intervention strategy should be implemented, especially regarding the role of education of children and families in taking up this healthy dietary style.

Polyphenols and IUGR Pregnancies: Effects of the Antioxidant Hydroxytyrosol on the Hippocampus Proteome in a Porcine Model

Supplementation of a mother’s diet with antioxidants such as hydroxytyrosol (HTX) has been proposed to ameliorate the adverse phenotypes of foetuses affected by intrauterine growth restriction (IUGR). Our previous studies showed, in a porcine model of IUGR, an effect of maternal HTX supplementation on the neurotransmitter profile of several brain areas and the morphology of the hippocampus in 100 days old foetuses. The present study analyzed the impact of maternal HTX supplementation on the hippocampus proteome at this foetal age by TMT10plex labelling. Eleven differentially abundant proteins were identified by comparing both conditions, and eight of them downregulated and three upregulated in the HTX-treated group. The downregulated proteins were mainly involved in protein synthesis and RNA metabolism and may explain the differences in neuron differentiation in the HTX-treated group. The upregulated proteins were related to cell detoxification and could represent a potential mechanism to explain the neuroprotective effect of HTX.

Comment on Yeste et al. Polyphenols and IUGR Pregnancies: Intrauterine Growth Restriction and Hydroxytyrosol Affect the Development and Neurotransmitter Profile of the Hippocampus in a Pig Model. Antioxidants 2021, 10, 1505

Intrauterine growth restriction (IUGR) affects 5–10% of newborns and increases the risks of intrauterine demise, neonatal morbidity, and death. In their recent publication, Yeste et al. found the benefits of hydroxytyrosol supplementation on brain remodeling from an IUGR pig model. Additionally, we found a significant decrease in phenolic alcohol (tyrosol and hydroxytyrosol) intake in IUGR pregnant women. Altogether, these findings support the notion that dietetic interventions, through supplementation but mostly via a balanced diet, can ameliorate IUGR complications. Furthermore, diet intervention combined with early biomarkers may allow clinicians to eventually anticipate IUGR diagnosis and help avoid one of the most frequent causes of newborn mortality and morbidity.

Adherence to the Mediterranean Diet in Pregnancy and Its Benefits on Maternal-Fetal Health: A Systematic Review of the Literature

Introduction

Pregnancy is a transcendent period for the mother and the fetus, characterized by an increase on energy requirements. Mediterranean diet (MD) is considered a healthy eating pattern that can provide the nutritional requirements of pregnancy and protect from the development of obstetric pathologies.

Objective

To know the relationship between adherence to the MD and its maternal-fetal benefits.

Methodology

A systematic review was conducted by identifying articles in the PubMed and Cochrane databases. The publication date of the studies was between 2010 and 2020, and the inclusion criteria established were that the articles were written in English and Spanish and were accessible in full text. Studies concerning assisted reproduction, gene modulation, conference abstracts, systematic reviews, and pilot studies were excluded.

Results

Finally, a total of 14 studies were included in the review. The association between the MD and the reduction of some pathologies of pregnancy, such as gestational diabetes, overweight or obesity, sleep quality, complications of childbirth, urinary tract infections (UTIs), and alterations in fetal growth was demonstrated, as well as perinatal problems, including birth weight, prematurity, gastroschisis, and other childhood problems.

Conclusion

The MD is an optimal diet to consume during pregnancy.

The impact a Mediterranean Diet in the third trimester of pregnancy has on neonatal body fat percentage

Maternal diet during pregnancy has long been recognised as an important determinant of neonatal outcomes and child development. Infant body composition is a potentially modifiable risk factor for predicting future health and metabolic disease. Utilising the Mediterranean Diet Score, this study focused on how different levels of Mediterranean Diet adherence (MDA) in pregnancy influence body fat percentage of the infant. Information on 458 pregnant women in their third trimester of pregnancy and their infants was obtained from The ORIGINS Project. The data included MDA score, body composition measurements using infant air displacement plethysmography (PEA POD), pregnancy, and birth information. Infants born to mothers with high MDA had a body fat percentage of 11.3%, whereas infants born to mothers with low MDA had a higher body fat percentage of 13.3% (p = 0.010). When adjusted for pre-pregnancy body mass index and infant sex, a significant result remained between high vs. low MDA and infant fat mass (FM) (2.5% less FM p = 0.016). This study suggests that high MDA in pregnancy was associated with a reduced body fat percentage in the newborn. Future studies are needed to understand whether small but significant changes in FM persist throughout childhood.

Maternal Dietary Quality and Dietary Inflammation Associations with Offspring Growth, Placental Development, and DNA Methylation

The ‘Developmental Origins of Health and Diseases’ hypothesis posits that prenatal maternal diet influences offspring growth and later life health outcomes. Dietary assessment has focused on selected nutrients. However, this approach does not consider the complex interactions between foods and nutrients. To provide a more comprehensive approach to public health, dietary indices have been developed to assess dietary quality, dietary inflammation and risk factors for non-communicable diseases. Thus far, their use in the context of placental development is limited and associations with offspring outcomes have been inconsistent. Although epidemiological studies have focused on the role of maternal diet on foetal programming, the underlying mechanisms are still poorly understood. Some evidence suggests these associations may be driven by placental and epigenetic changes. In this narrative review, we examine the current literature regarding relationships between key validated diet quality scores (Dietary Inflammatory Index [DII], Mediterranean diet [MD], Healthy Eating Index [HEI], Alternative Healthy Eating Index [AHEI], Dietary Approaches to Stop Hypertension [DASH], Glycaemic Index [GI] and Glycaemic Load [GL]) in pregnancy and birth and long-term offspring outcomes. We summarise findings, discuss potential underlying placental and epigenetic mechanisms, in particular DNA methylation, and highlight the need for further research and public health strategies that incorporate diet quality and epigenetics.

Adherence to Mediterranean diet impacts gastrointestinal microbial diversity throughout pregnancy

Background

Consumption of a diet with high adherence to a Mediterranean diet pattern (MDP) has been associated with a favorable gastrointestinal tract (GIT) microbiome. A healthy GIT microbiome in pregnancy, as defined by increased alpha diversity, is associated with lower chance of adverse perinatal outcomes. This study aimed to evaluate the impact of adherence to an MDP on GIT microbial diversity longitudinally throughout pregnancy.

Methods

Adherence to MDP was scored by the Alternate Mediterranean (aMED) Diet Quality Score, after being applied to a validated Food Frequency Questionnaire. Association of aMED Scores with GIT alpha diversity profiles were compared linearly and across time using a linear mixed model, including covariates of age, body mass index (BMI), ethnicity, and parity.

Results

Forty-one participants of Filipino, Japanese, Native Hawaiian, and Non-Hispanic White descent provided dietary information and microbiome samples during each trimester of pregnancy. Alpha diversity profiles changed over gestation, with decreased microbial diversity in the third trimester. aMED scores positively correlated with Chao1 Index and Observed Species Number (r = 0.244, p = 0.017, and r = 0.233, p = 0.023, respectively). The strongest association was detected in the third trimester (Chao 1: r = 0.43, p = 0.020, Observed Species Number: r = 0.41, p = 0.026). Participants with higher aMED scores had higher relative abundance of Acidaminoacaeae at the family level (p = 0.0169), as well as higher abundance of several species known to increase production of short chain fatty acids within the GIT.

Conclusions

Adherence to MDP pattern is associated with increased maternal GIT microbial diversity, and promotes the abundance of bacteria that produce short chain fatty acids. Increased consumption of fruits, vegetables and legumes with low red meat consumption were key components driving this association. The effect of nutrition however, was less of an effect than pregnancy itself. Further studies are needed to determine if adherence to a Mediterranean diet translates not only into microbial health, but also into reduced risk of adverse pregnancy outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04033-8.

Maternal periconceptional nutrition matters. A scoping review of the current literature

BACKGROUND

The importance of nutrition in reproductive health is widely acknowledged with special emphasis given to periconceptional maternal diet and its implications on embryo-fetal development, pregnancy complications, and the health of the offspring.

METHODS

Following the PRISMA guidelines, we searched for literature in PubMed, CINAHL, and WoS to gather newer information on how diet composition influences the concepts from the very early stages of pregnancy and how maternal health may be affected as well. Fifty-six studies published up to June 2020 met the inclusion criteria.

RESULTS

With its proportioned and diversified macronutrient composition, the Mediterranean Diet prevents congenital anomalies, preterm birth, hypertensive disorders, and gestational diabetes. Similar dietary patterns rich in vegetables, nuts, fish, and cereals increase the likelihood of conception and have a protective action, mediated by their antioxidant properties, against orofacial clefts, congenital heart and limb defects in the progeny. Conversely, the pro-inflammatory features of western diets, rich in processed foods and low in fruit content, diminish fertility, increase miscarriage rates, and enhance the risk of neural tube defects regardless of folate supplementation.

CONCLUSIONS

It may be concluded that within the multiple dietary options, some of them are soundly associated with beneficial effects for the mother and the newborn.Implications for practiceAn appropriate counseling must be offered to the woman of fertile age to make her aware of how periconceptional nutrition may help fulfill her reproductive expectations.

Mediterranean Diet and Lifestyle Habits during Pregnancy: Is There an Association with Small for Gestational Age Infants? An Italian Single Centre Experience

Background. The small-for-gestational-age (SGA) in infants is related to an increased risk of developing Non-Communicable Diseases later in life. The Mediterranean diet (MD) is related to lower odds of being SGA. The study explored retrospectively the association between SGA, maternal MD adherence, lifestyle habits and other SGA risk factors during pregnancy. Methods. One hundred women (16–44 years) with a pregnancy at term were enrolled. Demographic data, parity, pre-gestational BMI, gestational weight gain, pregnancy-related diseases, and type of delivery were collected. The MD adherence (MEDI-LITE score ≥ 9), physical activity level, and smoking/alcohol consumption were registered. SGA neonates were diagnosed according to the neonatal growth curves. Results. Women were divided into “SGA group” vs. “non-SGA group”. The MD was adopted by 71% of women and its adherence was higher in the “non-SGA group” (p = 0.02). The prevalence of pregnancy-related diseases (gestational diabetes/pregnancy-induced hypertension) was higher in the “SGA group” (p = 0.01). The logistic regression showed that pregnancy-related diseases were the only independent risk factor for SGA. Conclusions. MD may indirectly reduce the risk of SGA since it prevents and exerts a positive effect on pregnancy-related diseases (e.g., gestational diabetes and hypertension). The small sample size of women in the SGA group of the study imposes a major limitation to the results and conclusions of this research, suggesting however that it is worthy of further investigation.

Mediterranean-Style Diet and Birth Outcomes in an Urban, Multiethnic, and Low-Income US Population

Findings on the role of Mediterranean-style diet (MSD) on duration of pregnancy and birth weight have been inconsistent and based largely on Non-Hispanic white populations, making it unclear as to whether they could extend to African Americans who are at a higher risk of unfavorable birth outcomes. Our study addresses this gap using a large urban, multiethnic, predominantly low-income cohort of mother-infant dyads from Boston, MA, USA. Dietary information was obtained via food frequency questionnaires; health information including birth outcomes were extracted from medical records. A Mediterranean-style diet score (MSDS) was formulated based on intake history, and linear and log-binomial regressions were performed to assess its association with birth outcomes. After adjustment, the lowest MSDS quintile from the overall sample was found to be associated with an increased relative risk (RR) of overall preterm birth (RR 1.18; 95% CI: 1.06-1.31), spontaneous preterm birth (1.28; 1.11-1.49), late preterm birth (1.21; 1.05-1.39), and low birth weight (1.11; 1.01-1.22), compared to the highest quintile. The findings were similar for the African American sample. Our study adds to the current understanding of the diet's influence on birth outcomes by demonstrating that adherence to MSD may improve birth outcomes for African American women.

Maternal Adherence to the Mediterranean Diet during Pregnancy: A Review of Commonly Used a priori Indexes

Currently, many a priori indexes are being used to assess maternal adherence to the Mediterranean diet (MD) during pregnancy but each with different components, cut-off points, and scoring systems. This narrative review aimed to identify all observational studies utilizing a priori indexes to assess maternal adherence to the MD during pregnancy. A systematic search was conducted in Pubmed until 1 July 2020. Among the 27 studies included, eight different a priori indexes were identified. Studies included a range of 5 to 13 dietary components in their indexes. Only three dietary components-vegetables, fruits, and fish-were common among all indexes. Dairy and alcohol were the only two components modified for pregnancy. All but one study either excluded alcohol from their index or reversed its scoring to contribute to decreased adherence to the MD. Approximately half of the studies established cut-off points based on the distribution of the study population; the others utilized fixed criteria. This review emphasizes the incongruent definitions of the MD impairing effective comparison among studies relating to maternal or offspring health outcomes. Future research should carefully consider the heterogeneous definitions of the MD in a priori indexes and the relevance of incorporating pregnancy-specific nutritional requirements.

Nutrition in Reproductive Health: Nutritional Conditioning Factors during Pregnancy and Its Impact on Health

During the gestational period, women need to have optimal health to meet fetal requirements for growth and development. Nutrition is one of the most important factors that can ensure a mother`s health and also that of their offspring. The role of maternal diet, before and during pregnancy, has been associated with adverse birth outcomes and a worsening of maternal health. Medical conditions that are closely related to dietary intake and may affect women before or during pregnancy have also been associated with the appearance of pathology in a newborn. To date, several studies have been carried out in order to identify the role of diet as a factor associated with child physiological and psychological health, both in the short and long term. Educating mothers regarding the influence of maternal dietary intake during pregnancy on infants’ health could represent a simple but effective target for public health policies to improve pregnancy nutrition, and therefore help to avoid newborn diseases through the development.

Adherence to Mediterranean Diet and Maternal Lifestyle during Pregnancy: Island-Mainland Differentiation in the CRIBS Birth Cohort

Maternal nutrition and lifestyle in pregnancy are important modifiable factors for both maternal and offspring's health. Although the Mediterranean diet has beneficial effects on health, recent studies have shown low adherence in Europe. This study aimed to assess the Mediterranean diet adherence in 266 pregnant women from Dalmatia, Croatia and to investigate their lifestyle habits and regional differences. Adherence to the Mediterranean diet was assessed through two Mediterranean diet scores. Differences in maternal characteristics (diet, education, income, parity, smoking, pre-pregnancy body mass index (BMI), physical activity, contraception) with regards to location and dietary habits were analyzed using the non-parametric Mann-Whitney U test. The machine learning approach was used to reveal other potential non-linear relationships. The results showed that adherence to the Mediterranean diet was low to moderate among the pregnant women in this study, with no significant mainland-island differences. The highest adherence was observed among wealthier women with generally healthier lifestyle choices. The most significant mainland-island differences were observed for lifestyle and socioeconomic factors (income, education, physical activity). The machine learning approach confirmed the findings of the conventional statistical method. We can conclude that adverse socioeconomic and lifestyle conditions were more pronounced in the island population, which, together with the observed non-Mediterranean dietary pattern, calls for more effective intervention strategies.

Maternal dietary patterns during pregnancy derived by reduced-rank regression and birth weight in the Chinese population

Few studies have investigated the association between maternal dietary patterns (DP) during pregnancy, derived from reduced-rank regression (RRR), and fetal growth. This study aims to identify DP during pregnancy associated with macro- and micronutrient intakes, using the RRR method, and to examine their relationship with birth weight (BW). We used data of 7194 women from a large-scale cross-sectional survey in Northwest China. Dietary protein, carbohydrate, haem Fe density and the ratio of PUFA and MUFA:SFA were used as the intermediate variables in the RRR model to extract DP. Generalised estimating equation models were applied to evaluate the associations between DP and BW and related outcomes (including BW z-score, low birth weight (LBW) and small for gestational age (SGA)). Four DP during pregnancy were identified. Socio-demographically disadvantaged pregnant women were more likely to have lower BW and lower adherence to DP1 (high legumes, soyabean products, vegetables and animal-source foods, with relative low wheat and oils). Women with medium and high adherence to DP1 had significantly increased BW (medium 28·6 (95 % CI 7·1, 50·1); high 25·2 (95 % CI 2·7, 47·6)) and BW z-score and had significantly reduced risks of LBW and SGA. The associations were stronger among women with babies <3100 g. There is no association between other DP and outcomes. Higher adherence to the DP that was high in legumes, soyabean products, vegetables and animal-source foods was associated with improved BW in the Chinese pregnant women, particularly among those with disadvantageous socio-demographic conditions.

Maternal diets enriched in olive oil regulate lipid metabolism and levels of PPARs and their coactivators in the fetal liver in a rat model of gestational diabetes mellitus

In a rat model of gestational diabetes mellitus (GDM) programmed in the offspring of neonatal streptozotocin-induced (nSTZ) diabetic rats, lipids are accumulated in the fetal liver in a sex-dependent way. Here, we evaluated whether maternal diets enriched in olive oil in rats that will develop GDM ameliorate lipid metabolic impairments in the fetal livers. Pregnant offspring of control and nSTZ diabetic rats (F0) were fed a 6% olive oil-supplemented diet throughout the F1 gestation. We evaluated maternal metabolic parameters as well as lipid content, expression of lipid metabolizing enzymes and protein expression of PLIN2, PPARs and PPAR coactivators in the fetal livers. The offspring of nSTZ diabetic rats developed GDM regardless of the maternal treatment. Hypertriglyceridemia in GDM rats was prevented by the olive oil-enriched maternal treatment. In the livers of male fetuses of GDM rats, the maternal olive oil-supplemented diet prevented lipid overaccumulation and prevented the increase in PPARγ and PPARδ levels. In the livers of female fetuses of GDM rats, the maternal olive oil supplementation prevented the increase in PPARδ levels and the reduction in PGC1α levels, but did not prevent the reduced lipid content. Control and GDM rats showed a reduction of lipid metabolic enzymes in the fetal livers, which was associated with reduced levels of the PPAR coactivators PGC-1α and SRC-1 in males and of SRC-1 in females. These results suggest powerful effects of a maternal olive oil-supplemented diet in the fetal liver, possibly providing benefits in the fetuses and offspring from GDM rats.

Diet as a counteracting agent of the effect of some well-known risk factors for small for gestational age

OBJECTIVE

The aim of this study was to assess whether diet variables can neutralize the risk produced by three well-known risk factors for being small for gestational age: smoking, body mass index (BMI) ˂20 kg/m², and having a previous preterm/low birth weight (LBW) newborn.

METHODS

A matched case control study was conducted (518 cases and 518 controls of pregnant women) in Spain. We collected data on demographic characteristics, socioeconomic status, toxic habits, and diet. Dietary intake during pregnancy was assessed using a validated food frequency questionnaire, categorized into quintiles. Adjusted odds ratios (aORs) and their 95% confidence intervals (CI) were estimated by conditional regression logistic models.

RESULTS

Women who smoked during pregnancy had a 78% increased risk for having an SGA newborn (aOR, 1.78; 95% CI, 1.28-2.74). Lean women (BMI ˂ 20 kg/m² before pregnancy) augmented the risk 139% (aOR, 2.39; 95% CI, 1.68-3.40), and those with a previous SGA-LBW an increase of 160% (aOR, 2.60; 95% CI, 1.53-4.37). Smoking in women with a fruit intake of ≥421 g/d was not associated with a higher risk for SGA versus non-smoking women with the same fruit intake (aOR, 0.98; 95% CI, 0.41-2.33). A BMI <20 kg/m² with an intake of ≥33 g/d of legumes did not increase the risk for SGA versus women with a BMI ≥20 kg/m² with the same legume intake (aOR, 1.35; 95% CI, 0.54-3.37). Diet did not modify the risk by having a previous SGA-LBW newborn.

CONCLUSIONS

Smoking and leanness increased the SGA risk; nevertheless foods such as fruit, fish, and legumes, as well as intake of vitamins D and B₃ and ω-3 marine fatty acids, may "at" least partially counteract this increase.

Association between low dairy intake during pregnancy and small for gestational age infants

Maternal nutrition is recognized as one of the main determinants of fetal growth. We analyzed the risk of having a Small for Gestational Age (SGA) newborn according to maternal dairy intake during pregnancy. A matched case-control study was conducted in Spain. Dietary intake during pregnancy was assessed using a validated Food Frequency Questionnaire. Odds ratios (OR) and their 95% confidence intervals (CI) were estimated using conditional logistic regression models. 518 cases (SGA) and 518 controls (adequate birth weight) were included. Most study participants did not meet the current recommendations for dairy intake (78.6% cases and 80.2% controls). Intake of dairy products was not associated with a lower frequency of SGA, aOR_{Q4 vs. Q1} = 1.12 (95% CI 0.73, 1.70), and aOR_{Q5 vs. Q1} = 1.44 (95% CI 0.92, 2.26). Our results suggest that a low dairy intake during pregnancy is not associated with an increased risk of SGA; possibly due to the low consumption of dairy in both groups.

The association of maternal dietary folate intake and folic acid supplementation with small-for-gestational-age births: a cross-sectional study in Northwest China

The effect of maternal folate intake on small-for-gestational-age (SGA) births remains inconclusive. The present study aimed to investigate the associations of maternal folate intake from diet and supplements with the risk of SGA births using data from a cross-sectional study in Shaanxi Province of Northwest China. A total of 7307 women who were within 12 months (median 3; 10th–90th percentile 0–7) after delivery were included. Two-level models were adopted to examine the associations of folate (dietary folate, supplemental folic acid and total folate) intake with the risk of SGA births and birth weight Z score, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results showed that a higher supplemental folic acid intake during the first trimester was negatively associated with the risk of SGA births (≤60 d v. non-use: OR 0·80; 95 % CI 0·66, 0·96; &gt;60 d v. non-use: OR 0·78; 95 % CI 0·65, 0·94; Ptrend = 0·010; per 10-d increase: OR 0·97; 95 % CI 0·95, 0·99). A higher total folate intake during pregnancy was associated with a reduced risk of SGA births (highest tertile v. lowest tertile: OR 0·77; 95 % CI 0·64, 0·94; Ptrend = 0·010; per one-unit increase in the log-transformed value: OR 0·81; 95 % CI 0·69, 0·95). A similar pattern was observed for the birth weight Z score. Our study suggested that folic acid supplementation during the first trimester and a higher total folate intake during pregnancy were associated with a reduced risk of SGA births.

Obesity and the Mediterranean Diet: A Review of Evidence of the Role and Sustainability of the Mediterranean Diet

Several different socio-economic factors have caused a large portion of the population to adopt unhealthy eating habits that can undermine healthcare systems, unless current trends are inverted towards more sustainable lifestyle models. Even though a dietary plan inspired by the principles of the Mediterranean Diet is associated with numerous health benefits and has been demonstrated to exert a preventive effect towards numerous pathologies, including obesity, its use is decreasing and it is now being supplanted by different nutritional models that are often generated by cultural and social changes. Directing governments' political actions towards spreading adherence to the Mediterranean Diet's principles as much as possible among the population could help to tackle the obesity epidemic, especially in childhood. This document intends to reiterate the importance of acting in certain age groups to stop the spread of obesity and proceeds with a critical review of the regulatory instruments used so far, bearing in mind the importance of the scientific evidence that led to the consideration of the Mediterranean Diet as not just a food model, but also as the most appropriate regime for disease prevention, a sort of complete lifestyle plan for the pursuit of healthcare sustainability.

Effect of Adherence to Mediterranean Diet during Pregnancy on Children's Health: A Systematic Review

The traditional Mediterranean diet has been shown to be a healthy eating pattern that protects against the development of many diseases in adults and children. Pregnancy is a critical period of plasticity during which foetal development may be significantly influenced by different environmental factors, including maternal nutrition. In this context, several studies have examined the potential benefits of adherence to a Mediterranean diet during pregnancy on birth outcomes, considering the Mediterranean diet as a whole rather than focusing on the effect of its individual components. In this review, we systematically summarized and discussed results of studies investigating the protective role of Mediterranean diet against foetal growth, prematurity, neural tube defects and other congenital pathologies, asthma and allergy, body weight and metabolic markers. Although current data are insufficient and randomized control trials are needed, growing evidence suggests the beneficial effect of the Mediterranean diet during pregnancy on children's health. In this sense, strategies aiming to promote adherence to this dietary pattern might be of considerable importance to public health.

Types of Carbohydrates Intake during Pregnancy and Frequency of a Small for Gestational Age Newborn: A Case-Control Study

The objective of this study was to assess the relationship between consumption of different types of carbohydrates (CHO) during pregnancy and the risk of having a small for gestational age (SGA) newborn. A retrospective matched case–control design was carried out with a total of 518 mother-offspring pairs. A total of 137 validated items were included in the food frequency questionnaire (FFQ). Conditional logistic regression models were used to calculate crude odds ratios (cORs) and adjusted odds ratios (aORs) with 95% confidence intervals (CIs). Having more than 75 g/day of brown bread showed an inverse association with SGA (aOR = 0.64, CI 0.43–0.96). In contrast, an intake of industrial sweets more than once a day (aOR = 2.70, CI 1.42–5.13), or even 2–6 times a week (aOR = 1.84, CI 1.20–2.82), increased the odds of having a SGA newborn. During pregnancy, the higher the increase of wholegrain cereal and bread, the lower the possibility of having a SGA newborn, but the opposite occurred with refined sugar products—just consuming industrial bakery products or pastries twice a week increased the odds of having an SGA infant. Case–control studies cannot verify causality and only show associations, which may reflect residual confusion due to the presence of unknown factors. It is possible that a high consumption of sugary foods is a marker of a generally poor lifestyle.

The Effect of Exclusive Olive Oil Consumption on Successful Aging: A Combined Analysis of the ATTICA and MEDIS Epidemiological Studies

The consumption of dietary fats, which occur naturally in various foods, poses important impacts on health. The aim of this study was to elucidate the association of exclusive use of olive oil for culinary purposes with successful aging in adults aged >50 years old and residing in Greece. Use of olive oil in food preparation and bio-clinical characteristics of the Greek participants enrolled in the ATTICA (n = 1128 adults from Athens metropolitan area) and the MEDiterranean Islands Study (MEDIS) (n = 2221 adults from various Greek islands and Mani) studies, were investigated in relation to successful aging (SA). Participants were divided into the following three categories: (a) no olive oil consumption; (b) combined consumption of olive oil and other dietary fats; and (c) exclusive olive oil consumption. The SA was measured using the previously validated successful aging index (SAI). After adjusting for age, sex, and smoking habits, combined consumption of olive oil and other fats (vs. no olive oil use) was not significantly associated with SAI levels (p = 0.114). However, exclusive olive oil intake (vs. no use of olive oil) was significantly associated with SAI (p = 0.001), particularly among those aged older than 70 years. Therefore, the exclusive consumption of olive oil, as opposed to either combined or no olive oil consumption, beneficially impacts successful aging, particularly among individuals over 70 years of age. Primary public health prevention strategies should seek to encourage the enhanced adoption of such dietary practices in order to promote healthy aging and longevity.

A High Adherence to Six Food Targets of the Mediterranean Diet in the Late First Trimester is Associated with a Reduction in the Risk of Materno-Foetal Outcomes: The St. Carlos Gestational Diabetes Mellitus Prevention Study

A prenatal diet affects materno-foetal outcomes. This is a post hoc analysis of the St. Carlos gestational diabetes mellitus (GDM) Prevention Study. It aims to evaluate the effect of a late first-trimester (>12 gestational weeks) degree of adherence to a MedDiet pattern-based on six food targets-on a composite of materno-foetal outcomes (CMFCs). The CMFCs were defined as having emergency C-section, perineal trauma, pregnancy-induced hypertension and preeclampsia, prematurity, large-for-gestational-age, and/or small-for-gestational-age. A total of 874 women were stratified into three groups according to late first-trimester compliance with six food targets: >12 servings/week of vegetables, >12 servings/week of fruits, <2 servings/week of juice, >3 servings/week of nuts, >6 days/week consumption of extra virgin olive oil (EVOO), and ≥40 mL/day of EVOO. High adherence was defined as complying with 5⁻6 targets; moderate adherence 2⁻4 targets; low adherence 0⁻1 targets. There was a linear association between high, moderate, and low adherence, and a lower risk of GDM, CMFCs, urinary tract infections (UTI), prematurity, and small-for-gestational-age (SGA) newborns (all p < 0.05). The odds ratios (95% CI) for GDM and CMFCs in women with a high adherence were 0.35((0.18⁻0.67), p = 0.002) and 0.23((0.11⁻0.48), p < 0.001), respectively. Late first-trimester high adherence to the predefined six food targets is associated with a reduction in the risk of GDM, CMFCs, UTI, prematurity, and SGA new-borns.