Maternal Food Consumption during Pregnancy and the Longitudinal Development of Childhood Asthma

The impact of perinatal and at birth risk factors on the progression from preschool wheezing to adolescent asthma

Asthma is a global health concern affecting millions of children and adolescents. This review focuses on the possible factors that are associated with the transition from preschool wheezing to childhood asthma and highlights the significance of early-life environmental exposures during pregnancy and the first 6 months of life in shaping allergies and asthma. We observed a scarcity of studies investigating this subgroup, with most focusing on wheezing trajectories. We undertook a thorough investigation of diverse perinatal exposures that have the potential to impact this transition. These factors include maternal asthma, smoking during pregnancy, diet, prepregnancy weight, infant birthweight, gestational age, and breastfeeding. Although limited, studies do suggest that maternal asthma increases the likelihood of preschool wheeze in offspring that persists through childhood with potential asthma progression. Findings concerning other perinatal exposures remain inconsistent. Further research is needed to identify asthma progression risk factors and assess perinatal exposure effects.

An Evaluation of Food and Nutrient Intake among Pregnant Women in The Netherlands: A Systematic Review

Nutritional deficiencies during pregnancy can have serious consequences for the health of the (unborn) child. This systematic review provides an updated overview of the available food and nutrient intake data for pregnant women in The Netherlands and an evaluation based on the current recommendations. Embase, MEDLINE, and national institute databases were used. Articles were selected if they had been published since 2008 and contained data on food consumption, nutrient intake, or the status of healthy pregnant women. A qualitative comparison was made with the 2021 Dutch Health Council recommendations and reference values. A total of 218 reports were included, representing 54 individual studies. Dietary assessments were primarily performed via food frequency questionnaires. Protein, vitamin A, thiamin, riboflavin, vitamin B₆, folate, vitamin B₁₂, vitamin C, iron, calcium, and magnesium intakes seemed to be adequate. For folate and vitamin D, supplements were needed to reach the recommended intake. The reasons for concern are the low intakes of fruits, vegetables, and (fatty) fish, and the intakes of alcohol, sugary drinks, and salt. For several foods and nutrients, no or limited intake data were found. High-quality, representative, and recent data are needed to evaluate the nutrient intake of pregnant women in order to make accurate assessments and evaluations, supporting scientific-based advice and national nutritional policies.

A Synopsis of Guidance for Allergic Rhinitis Diagnosis and Management From ICAR 2023

An updated edition of the International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR) has recently been published. This consensus document, which included the participation of 87 primary authors and 40 additional consultant authors, who critically appraised evidence on 144 individual topics concerning allergic rhinitis, provides guidance for health care providers using the evidence-based review with recommendations (EBRR) methodology. This synopsis highlights topical areas including pathophysiology, epidemiology, disease burden, risk and protective factors, evaluation and diagnosis, aeroallergen avoidance and environmental controls, single and combination pharmacotherapy options, allergen immunotherapy (subcutaneous, sublingual, rush, cluster), pediatric considerations, alternative and emerging therapies, and unmet needs. Based on the EBRR methodology, ICAR:AR includes strong recommendations for the treatment of allergic rhinitis: (1) for the use of newer generation antihistamines compared with first-generation alternatives, intranasal corticosteroid, intranasal saline, combination therapy with intranasal corticosteroid plus intranasal antihistamine for patients not responding to monotherapy, and subcutaneous immunotherapy and sublingual tablet immunotherapy in properly selected patients; (2) against the use of oral decongestant monotherapy and routine use of oral corticosteroids.

Sphagneticola trilobata (L.) Pruski-derived kaurenoic acid prevents ovalbumin-induced asthma in mice: Effect on Th2 cytokines, STAT6/GATA-3 signaling, NFκB/Nrf2 redox sensitive pathways, and regulatory T cell phenotype markers

ETHNOPHARMACOLOGICAL RELEVANCE

Sphagneticola trilobata (L.) Pruski is used in traditional medicine in Brazil for inflammatory diseases treatment including asthma. The diterpene kaurenoic acid (KA) is one of its active compounds, but whether KA activity could explain the traditional use of S. trilobata in asthma is unknown.

AIM

Investigate KA effect and mechanisms in asthma.

METHODS

Experimental asthma was induced by ovalbumin immunization and challenge in male Swiss mice. KA (0.1-10 mg/kg, gavage) was administered 1 h before the ovalbumin challenge. Total leukocytes, eosinophil, and mast cell were counted in bronchoalveolar lavage fluid (BALF), and lung histopathology was performed. Lung mRNA expression of Th2 and regulatory T cells markers, and BALF type 2 cytokine production were quantitated. NFκB activation and oxidative stress-related components in pulmonary tissue were measured.

RESULTS

KA inhibited the migration of total leukocytes and eosinophils to BALF, reduced lung histopathology (inflammatory cells and mast cells), mRNA expression of IL-33/ST2, STAT6/GATA-3 and NFκB activation in the lung, and reduced IL-33, IL-4, IL-5 production in the BALF. KA also reduced the mRNA expression of iNOS and gp91^phox, and superoxide anion production accompanied by the induction of Nrf2, HO-1 and NQO1 mRNA expression, thus, exerting an antioxidant effect. Finally, KA induced nTreg-like and Tr1-like, but not Th3-like markers of suppressive T cell phenotypes in the lung tissue.

CONCLUSION

KA prevents antigen-induced asthma by down-regulating Th2 and NFκB/cytokine-related pathways, and up-regulating Nrf2 and regulatory T cells' markers. Thus, explaining the ethnopharmacological use of S. trilobata for the treatment of lung inflammatory diseases.

The association between sugar intake during pregnancy and allergies in offspring: a systematic review and a meta-analysis of cohort studies

CONTEXT

It has been hypothesized that a mother's diet during pregnancy may modulate her offspring's immune system development and lead to development of allergic diseases among offspring. However, the evidence for this is unclear and inconclusive.

OBJECTIVE

This systematic review was undertaken to examine the weight of evidence for causality from cohort studies on the association between maternal free sugar intake during pregnancy and development of allergies in offspring.

DATA SOURCES

Using a systematic search strategy, PubMed, SCOPUS, and Web of Science databases were searched from inception to May 2020.

DATA EXTRACTION

For the reporting of this systematic review, the PRISMA guideline was followed. Studies examining maternal sugar consumption during pregnancy (using self-reported data) and the development of allergic diseases among offspring (infancy to 5 years) were included.

DATA ANALYSIS

The Newcastle-Ottawa Scale quality assessment tool was used to assess the study quality. Meta-analysis was conducted using a random-effects model to synthesize the findings. Of 159 publications identified from the search, 5 articles with 4 unique cohort studies were included in this systematic review. The limited meta-analysis showed that a mother's increased free sugar intake during pregnancy was associated with an increased risk of developing asthma in offspring (odds ratio 1.07 [95% CI, 1.00 to 1.14; I2 = 0%]). High free sugar intake by the mother during pregnancy was also associated with increased odds of offspring (to age 7.7 years) developing other common allergies, including allergic rhinitis, atopy and eczema, wheeze, and food allergies.

CONCLUSION

From the limited evidence, this review suggests that high free sugar consumption during pregnancy may be associated with the development of allergies in offspring. Clinical guidelines and public health policy recommendations for maternal diet in pregnancy should include advice about reducing free sugar intake due to a possible association with allergies in offspring. However, recommendations should be made with caution considering other maternal and fetal risk factors.

Fish consumption during pregnancy and risk of allergic diseases in the offspring: A systematic review and meta-analysis

Although several studies have reported the beneficial effects of maternal fish consumption on allergy diseases in the offspring, the findings are conflicting. We summarized earlier data on the association between maternal fish intake and risk of allergy diseases in the offspring through a meta-analysis. A systematic literature search of relevant reports published in Medline/PubMed, ISI web of Science, EMBASE, SCOPUS and Google Scholar prior to February 2020 was conducted. All observational studies (cross-sectional, case-control or cohort) that examined the relationship between intake of maternal fish and risk of allergy diseases in the offspring were considered. Duplicate and non-related studies were excluded. In total, 31 studies on maternal fish consumption and risk of allergic diseases in the offspring were included. Greater maternal fish intake was associated with a reduced risk of wheeze (Pooled effect size: 0.97; 95% CI: 0.96-0.99) and food allergy (0.75; 95% CI: 0.64-0.88). Maternal fish consumption was not associated with risk of asthma (pooled effect size: 0.99; 95% CI: 0.89, 1.11), eczema (pooled effect size: 0.93; 95% CI: 0.84, 1.03), allergic rhinitis (pooled effect size: 0.91; 95% CI: 0.75, 1.09), and inhalant allergy (pooled effect size: 0.86; 95% CI: 0.66, 1.13). In non-linear dose-response meta-analysis, increased intake of fish during pregnancy (at the level of 50 to 200 grams per week) was associated with a reduced risk of eczema (P non-linearity = 0.042). Meta-regression of included studies revealed an inverse linear association between maternal fish intake and risk of eczema; such that every additional 30-gram per week consumption of fish during pregnancy was associated with a 4% reduced risk of eczema. We found that fish intake during pregnancy was associated with a lower risk of wheeze, eczema and food allergy in children. No significant association was seen between maternal fish consumption and risk of offspring's asthma, allergic rhinitis, and inhalant allergy.

Adherence to the Mediterranean Diet and Determinants Among Pregnant Women: The NELA Cohort

The Mediterranean diet represents one of the most studied dietary patterns; however, there is no single tool for measuring the grade of adherence and no single set of criteria for adapting these indices to pregnant women. We characterized the adherence to the Mediterranean diet (MDA) of pregnant women participating in the NELA (Nutrition in Early Life and Asthma) cohort and identified the sociodemographic determinants and lifestyle habits associated with a higher risk of a low MDA. Maternal diet during gestation was assessed by a validated Food Frequency Questionnaire (FFQ) (n = 665). We estimated the Relative Mediterranean Diet score (rMED), Alternative Mediterranean Diet score (aMED), and the Alternate Healthy Eating Index-2010 (AHEI-2010). Multivariate regression models were performed to identify the sociodemographic and lifestyle factors associated with each index. Mothers with a lower age and more previous deliveries had a greater probability of low MDA (p < 0.05). For the aMED index only, mothers with university education and/or who practiced sport activities for two or more hours per week had a lower probability of a low MDA (p < 0.01). The three indices classified the NELA cohort as having a medium level of adherence. These results may be improved by designing intervention strategies and dietary recommendations for both maternal and offspring health.

[Diet and asthma: Better eating for better breathing?]

Inhaled therapies are the cornerstone of asthma treatment. However, according to national and international guidelines, non-pharmacological interventions should not be neglected in asthma. It has been demonstrated that a healthy diet is beneficial to general health. Recently, the effect of diet on asthma has been highlighted in many studies. Two diets have been particularly studied: the Mediterranean diet (high in fruits and vegetables and low in fat) and the Western diet (high in saturated fat and low in fruits and vegetables). A beneficial effect of the Mediterranean diet and deleterious effect of the Western diet on the development or control of asthma has been shown in some studies even after adjustment for overweight. Study findings have not been unanimous, probably related to the complexity of conducting studies on a diet that may change from day to day for any individual subject. In addition, the effect of physical exercise, which is known to be beneficial in asthma, is rarely taken into account in these studies. However, studies on diet are becoming more complex with the use of specific dietary indices, which should bring interesting data in the future.

Association between maternal vegetable intake during pregnancy and allergy in offspring: Japan Environment and Children's Study

The association between maternal diet during pregnancy and allergy in offspring remains contentious. Here, we examined the association between maternal intake of vegetables and related nutrients during pregnancy and allergic diseases in offspring at one year of age. A cohort of 80,270 pregnant women enrolled in the Japan Environment and Children's Study were asked to respond to a food frequency questionnaire during pregnancy and the International Study of Asthma and Allergies in Childhood questionnaire at one year postpartum. The women were categorized into quintiles according to the energy-adjusted maternal intake of vegetables and related nutrients. Using the categorizations as exposure variables, the adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were determined for the allergic outcomes, including asthma, wheeze, atopic dermatitis, eczema, and food allergy, in the offspring per quintile at one year of age. Of the 80,270 participants, 2,027 (2.5%), 15,617 (19.6%), 3,477 (4.3%), 14,929 (18.7%), 13,801 (17.2%), and 25,028 (31.3%) children experienced asthma, wheeze, atopic dermatitis, eczema, food allergy, and some form of allergic disease, respectively. The aORs of each quintile of maternal vegetable intake for all allergic outcomes were close to 1.0 compared to the lowest quintile. The lowest aOR was found in the association of maternal cruciferous vegetable intake with asthma (aOR: 0.82, 95% CI: 0.70-0.96) and highest was found in the association of maternal total vegetable intake with atopic dermatitis (aOR: 1.17, 95% CI: 1.04-1.31). The risk of allergic outcomes for the various nutrients related to vegetable consumption was close to 1.0. The maternal intake of vegetables and various related nutrients during pregnancy had little or no association with any of the allergic outcomes, including asthma, wheezing, atopic dermatitis, eczema, and food allergy, in offspring at one year.

Dietary factors during pregnancy and atopic outcomes in childhood: A systematic review from the European Academy of Allergy and Clinical Immunology

RATIONALE

Allergic diseases are an increasing public health concern, and early life environment is critical to immune development. Maternal diet during pregnancy has been linked to offspring allergy risk. In turn, maternal diet is a potentially modifiable factor, which could be targeted as an allergy prevention strategy. In this systematic review, we focused on non-allergen-specific modifying factors of the maternal diet in pregnancy on allergy outcomes in their offspring.

METHODS

We undertook a systematic review of studies investigating the association between maternal diet during pregnancy and allergic outcomes (asthma/wheeze, hay fever/allergic rhinitis/seasonal allergies, eczema/atopic dermatitis (AD), food allergies, and allergic sensitization) in offspring. Studies evaluating the effect of food allergen intake were excluded. We searched three bibliographic databases (MEDLINE, EMBASE, and Web of Science) through February 26, 2019. Evidence was critically appraised using modified versions of the Cochrane Collaboration Risk of Bias tool for intervention trials and the National Institute for Clinical Excellence methodological checklist for cohort and case-control studies and meta-analysis performed from RCTs.

RESULTS

We identified 95 papers: 17 RCTs and 78 observational (case-control, cross-sectional, and cohort) studies. Observational studies varied in design and dietary intakes and often had contradictory findings. Based on our meta-analysis, RCTs showed that vitamin D supplementation (OR: 0.72; 95% CI: 0.56-0.92) is associated with a reduced risk of wheeze/asthma. A positive trend for omega-3 fatty acids was observed for asthma/wheeze, but this did not reach statistical significance (OR: 0.70; 95% CI: 0.45-1.08). Omega-3 supplementation was also associated with a non-significant decreased risk of allergic rhinitis (OR: 0.76; 95% CI: 0.56-1.04). Neither vitamin D nor omega-3 fatty acids were associated with an altered risk of AD or food allergy.

CONCLUSIONS

Prenatal supplementation with vitamin D may have beneficial effects for prevention of asthma. Additional nutritional factors seem to be required for modulating the risk of skin and gastrointestinal outcomes. We found no consistent evidence regarding other dietary factors, perhaps due to differences in study design and host features that were not considered. While confirmatory studies are required, there is also a need for performing RCTs beyond single nutrients/foods.

EAACI position paper on diet diversity in pregnancy, infancy and childhood: Novel concepts and implications for studies in allergy and asthma

To fully understand the role of diet diversity on allergy outcomes and to set standards for conducting research in this field, the European Academy of Allergy and Clinical Immunology Task Force on Diet and Immunomodulation has systematically explored the association between diet diversity and allergy outcomes. In addition, a detailed narrative review of information on diet quality and diet patterns as they pertain to allergic outcomes is presented. Overall, we recommend that infants of any risk category for allergic disease should have a diverse diet, given no evidence of harm and some potential association of benefit in the prevention of particular allergic outcomes. In order to harmonize methods for future data collection and reporting, the task force members propose relevant definitions and important factors for consideration, when measuring diet diversity in the context of allergy. Consensus was achieved on practice points through the Delphi method. It is hoped that the definitions and considerations described herein will also enable better comparison of future studies and improve mechanistic studies and pathway analysis to understand how diet diversity modulates allergic outcomes.

Prenatal Omega-3 and Omega-6 Polyunsaturated Fatty Acids and Childhood Atopic Dermatitis

BACKGROUND

Atopic dermatitis is a common childhood disease, potentially influenced by prenatal nutritional exposures such as polyunsaturated fatty acids (PUFAs).

OBJECTIVE

In a racially diverse cohort, we hypothesized that childhood atopic dermatitis would be associated with higher prenatal omega-6 (n-6) and lower omega-3 (n-3) PUFAs.

METHODS

We included mother-child dyads, births 2006 to 2011, enrolled in the University of Tennessee Health Sciences Center Conditions Affecting Neurocognitive Development in Early Childhood cohort. Primary exposures included second trimester plasma n-3 and n-6 PUFA status and the ratio of the two (n-6:n-3). We assessed child current atopic dermatitis symptoms in the previous 12 months at age approximately 4 to 6 years. We investigated the association between PUFA exposures and atopic dermatitis using multivariable logistic regression, adjusting for potential confounders. We assessed for effect modification by maternal prenatal smoking, atopic disease history, and child sex.

RESULTS

Among 1131 women, 67% were African American and 42% had an atopic disease history; 17% of children had atopic dermatitis. Higher prenatal n-6 PUFAs were associated with increased relative odds of child atopic dermatitis (adjusted odds ratio: 1.25; confidence interval: 1.01-1.54 per interquartile range difference), and interaction models demonstrated that this association was seen in dyads in which the women had a history of atopic disease. Neither prenatal n-3 PUFAs nor n-6:n-3 were associated with child atopic dermatitis.

CONCLUSION

In this racially diverse cohort, higher second trimester n-6 PUFAs were associated with atopic dermatitis in children of women with atopy. PUFAs may represent a modifiable risk factor for atopic dermatitis, particularly in individuals with a familial predisposition.

Nutritional Issues in Food Allergy

Diet and nutrition play an important role in the development and management of food allergy. The diet of expectant mothers can have an effect on their offspring in terms of allergic outcomes. A host of confounding factors may influence this, with a maternal diet rich in fruits and vegetables, fish, vitamin D-rich foods associated with a lower risk of allergic disease in their children. More surprisingly, the consumption of milk and butter has also been shown to have a protective effect, especially in a farm environment. Similarly, the diet of the infant can also be important, not only in terms of breast feeding, but also the timing of the introduction of complementary foods, the diversity of the diet and the effect of individual foods on the development of allergy. One factor which has clearly been shown not to influence the development of food allergy is allergen avoidance by expectant mothers. In the infant diet, the manipulation of the gut microbiome to prevent the development of atopic disease is clearly an area which promises much, although studies have yet to provide a breakthrough in the prevention of atopic dermatitis. More concrete evidence of the value of diet in prevention has come from studies evaluating infant eating patterns which may protect gut health, through the consumption of large amounts of home-processed fruits and vegetables. The consumption of fish during the first year of life has also been shown to be protective. The importance of nutritional issues in children and adults who have a food allergy has become much more accepted in recent years. The primary allergenic foods in infancy and childhood, milk, egg, wheat and soy are also ones which are present in many foods and thus their avoidance can be problematic from a nutritional perspective. Thus, children with a food allergy can have their growth compromised through avoidance, especially pre-diagnosis, when foods may be excluded without any expert nutritional input. The management of a food allergy largely remains the exclusion of the offending food(s), but it is now clear that in doing so, children in particular can be at nutritional risk if insufficient attention is paid to the rest of the diet. Adults with food allergy are often thought not to need nutritional counselling; however, many will exclude a wide range of foods due to anxiety about trace exposure, or similar foods causing reactions. The avoidance of staple foods such as milk and wheat are common, but substitute foods very often do not have comparable nutritional profiles. Adults may also be more susceptible to on-line promotion of extreme nutritional regimes which can be extremely harmful. All food allergic individuals, whatever their age, should have a nutrition review to ensure they are consuming a healthy, balanced diet, and are not avoiding food groups unnecessarily.

Respiratory

Lung disease rivals the position for the top cause of death worldwide. Causes and pathology of the myriad lung diseases are varied, yet nutrition can either affect the outcome or support treatment in the majority of cases. This chapter explores the modifiable risk factors, from lifestyle changes to dietary intake to specific nutrients, anti-nutrients, and toxins helpful for the nutritionist or dietitian working with lung disease patients. General lung health is discussed, and three major disease states are explored in detail, including alpha-1 antitrypsin deficiency, asthma, and idiopathic pulmonary fibrosis. Although all lung diseases have diverse causes, many integrative and functional medical nutrition therapies are available and are not being utilized in practice today. This chapter begins the path toward better nutrition education for the integrative and functional medicine professional.

Influence of prenatal and early-life exposures on food allergy and eczema in infancy: a birth cohort study

Background

Few prospective birth cohort studies are available on the effects of prenatal and early-life exposures on food allergy and eczema among Chinese children. The aim of this study was to evaluate the influence of prenatal and early-life exposures on food allergy and eczema during the first year of life in a prospective birth cohort study.

Methods

This study was based on a prospective, observational birth cohort of 976 mother-child pairs in three Streets in Changsha, China from January to December 2015. Data on prenatal, early-life exposures and allergic outcomes were obtained from questionnaires collected at birth, and 1, 3, 6, 8, and 12 months of age. Multivariate logistic regression models were performed to estimate the effects of prenatal and early-life exposures on food allergy and eczema.

Results

Common risk factors for food allergy and eczema in infancy were parental history of allergy, while moderate eggs consumption (3–4 times/week) during pregnancy was protective for both of them compared with low consumption (≤ 2 times/week). Factors only associated with food allergy were maternal aquatic products consumption during pregnancy, number of older siblings and age of solid food introduction, whereas factors only associated with eczema were maternal milk or milk products consumption during pregnancy, maternal antibiotic exposure during pregnancy, season of birth and antibiotic exposure through medication during the first year of life.

Conclusion

Our study suggests that factors associated with food allergy and eczema are multifaceted, which involving hereditary, environmental and nutritional exposures. Furthermore, differential factors influence the development of food allergy and eczema in infants.

Maternal diet before and during pregnancy and risk of asthma and allergic rhinitis in children

BACKGROUND

Consumption of certain foods during pregnancy has been shown to have beneficial effects on childhood asthma and allergic disease development and aggravation. However, most studies provide conflicting results and the relationships between maternal preconceptional diet and risks of childhood asthma and allergic disease have not previously been explored. The objective of this study was to assess maternal diet during the year before pregnancy and the last 3 months of pregnancy and investigate their associations with the risks of asthma, wheezing, allergic rhinitis and atopic dermatitis in young children.

METHODS

The study sample consisted of 1140 mother-child pairs from the EDEN cohort. Mothers had responded to the food frequency questionnaires used to assess diet before and during pregnancy. Children were followed up using health questionnaires. The health outcomes studied were: asthma, wheezing, allergic rhinitis and atopic dermatitis by the age of 3 years.

RESULTS

Using multivariable-adjusted logistic regression models, significant inverse associations were observed between cooked green vegetable consumption before pregnancy and childhood asthma; consumption of eggs and raw vegetables before and during pregnancy, consumption of grains before pregnancy, and consumption of cooked green vegetables during pregnancy and allergic rhinitis. For the first time, a significant positive association was found between meat intake during the preconceptional period and a risk of wheezing, allergic rhinitis and atopic dermatitis.

CONCLUSIONS

Based on our findings, preconceptional and prenatal maternal intake of certain type of food groups may be preventive against asthma, wheezing and allergic rhinitis, whereas higher maternal intake of meat before pregnancy may increase the risk of wheezing, allergic rhinitis and atopic dermatitis in young children.

Food Consumption, Nutrient Intake and Status during the First 1000 days of Life in the Netherlands: a Systematic Review

Adequate nutrition is essential for growth and development in early life. Nutritional data serves as a basis for national nutritional guidelines and policies. Currently, there is no insight into the availability of such data during the first 1000 days of life. Therefore, a systematic review was performed, following the PRISMA reporting guideline, to identify studies on food consumption, nutrient intake or status in the Netherlands. Potential gaps were identified, and the quality of the studies is discussed. The databases Embase and Medline were used, as well as databases from national institutes. Articles published in 2008-2018 were screened by two independent reviewers. In total 601 articles were identified, of which 173 were included. For pregnant women, 32 studies were available with nutritional data, for young children 40 studies were identified. No studies were available for breastfeeding women. A large variety of foods and nutrients were assessed, however certain nutrients were lacking (e.g., vitamin K). Overall, the studies had methodological limitations, making the data unsuitable to assess nutrient inadequacies. There is a need for recent, high quality nutritional research to strengthen the understanding of the nutritional needs and deficiencies during early life, and is fundamental for national guidelines and policies.

Food consumption and the risk of childhood allergy

Background

The prevalence of allergic conditions is increasing in most countries. One possible explanation may be childhood nutrition.

Objective

The aim of the study was to investigate the relationship between consumption of pre-specified types of food in school-aged children and presence of respiratory and allergic symptoms.

Methods

A total of 191 students aged 9-11 years were recruited from 5 schools to geographically cover all of Malta. Data was collected between October 2011 and February 2012. This was part of a bigger study which included clinical and environmental tests besides standardized health questionnaires. For the purposes of this part of the study only the health questionnaires were used. These standardized health questionnaires based on the International Study of Asthma and Allergies in Childhood (ISAAC) were used to identify the presence of respiratory and allergic symptoms and to identify the types of foods and the frequency of consumption of various types of foods.

Results

We found that milk, meat, butter, olive oil, and yoghurt consumption had a negative association with allergic symptoms in children, whilst fish consumption had a detrimental effect. These relationships remained significant after correction for paternal level of education.

Conclusion

The study highlights the fact that nutrition in early childhood may have a significant effect on the risk of allergic conditions. Our results, taken together with data in the literature, suggest that different types of fish might have had different effects. This is probably related to their different fatty acid constitution thus warranting further studies.

Prenatal Diet and the Development of Childhood Allergic Diseases: Food for Thought

PURPOSE OF REVIEW

The development of allergic disease is shaped by genetics and the environment, including diet. Many studies suggest a role for maternal diet during pregnancy. In this article, we discuss potential mechanisms by which specific nutrients, particular foods, and dietary patterns may influence allergic disease development and review studies examining the relationship between prenatal diet and the risk of childhood allergy.

RECENT FINDINGS

The combination of in utero exposures and genetic predisposition may contribute to the development of allergic disease by altering immune and organ development. Inflammation predominates in the first and third trimesters whereas the second trimester is characterized by anti-inflammatory and Th2 immune responses. Maternal dietary exposures during pregnancy may interact with inherited genetic risk factors influence immune system development. There are varied results regarding the impact of maternal prenatal diet on the development of childhood allergies. Well-designed randomized controlled studies are needed to clarify this area.

Fish and seafood consumption during pregnancy and the risk of asthma and allergic rhinitis in childhood: a pooled analysis of 18 European and US birth cohorts

Background

It has been suggested that prenatal exposure to n-3 long-chain fatty acids protects against asthma and other allergy-related diseases later in childhood. The extent to which fish intake in pregnancy protects against child asthma and rhinitis symptoms remains unclear. We aimed to assess whether fish and seafood consumption in pregnancy is associated with childhood wheeze, asthma and allergic rhinitis.

Methods

We pooled individual data from 60 774 mother-child pairs participating in 18 European and US birth cohort studies. Information on wheeze, asthma and allergic rhinitis prevalence was collected using validated questionnaires. The time periods of interest were: infancy (0-2 years), preschool age (3-4 years), and school age (5-8 years). We used multivariable generalized models to assess associations of fish and seafood (other than fish) consumption during pregnancy with child respiratory outcomes in cohort-specific analyses, with subsequent random-effects meta-analyses.

Results

The median fish consumption during pregnancy ranged from 0.44 times/week in The Netherlands to 4.46 times/week in Spain. Maternal fish intake during pregnancy was not associated with offspring wheeze symptoms in any age group nor with the risk of child asthma [adjusted meta-analysis relative risk (RR) per 1-time/week = 1.01, 95% confidence interval 0.97-1.05)] and allergic rhinitis at school age (RR = 1.01, 0.99-1.03). These results were consistently found in further analyses by type of fish and seafood consumption and in sensitivity analyses.

Conclusion

We found no evidence supporting a protective association of fish and seafood consumption during pregnancy with offspring symptoms of wheeze, asthma and allergic rhinitis from infancy to mid childhood.

Pregnancy diet and offspring asthma risk over a 10-year period: the Lifeways Cross Generation Cohort Study, Ireland

OBJECTIVE

The association of maternal pregnancy diet with offspring asthma risk have been reported. However, literature on longitudinal patterns of asthma risk relative to intrauterine nutrient exposure is limited. We aimed to establish whether vegetable, oily fish and vitamin D intake during pregnancy are associated with childhood asthma risk over a 10-year period in the Irish Republic.

DESIGN

Mother-child pairs (n=897) from the Lifeways prospective birth cohort, with data on nutrient intake during pregnancy and asthma status, respectively, were eligible for inclusion in the analysis. Data on socioeconomic and morbidity indicators over 10 years of follow-up on mothers and the index child were collected through self-administered questionnaires. Asthma status as diagnosed by the general practitioner at any time point over 10 years was related to maternal vegetable, oily fish and vitamin D intake during pregnancy, while adjusting for gestational age, socioeconomic status, smoking at delivery, breast feeding, season of birth and supplement use. Data were modelled with a marginal model on correlated observations over time within individuals.

RESULTS

In the fully adjusted model, asthma was inversely associated with higher daily average intake of oily fish (OR 0.23 per serving/day, 95% CI 0.04 to 1.41) and of vegetables (OR 0.96 per serving/day, 95% CI 0.88 to 1.05), but the confidence limits overlapped 1. A higher daily vitamin D intake was associated with reduced odds of asthma (OR 0.93 per μg/day, 95% CI 0.89 to 0.98).

CONCLUSION

This analysis suggests higher daily average intake of vitamin D in pregnancy is associated with asthma risk in offspring over the first 10 years of life.

Maternal vegetable intake in early pregnancy and wheeze in offspring at the age of 2 years

BACKGROUND/OBJECTIVES

Vegetable intake during childhood may reduce the risk of subsequent asthma. We verified the effect of maternal intake during pregnancy on asthma risk in offspring, which has rarely been studied.

SUBJECTS/METHODS

In a hospital-based birth cohort study conducted in Tokyo, we administered a food frequency questionnaire at two periods during the respondents' pregnancy: early and mid to late periods. In addition, a questionnaire including the International Study of Asthma and Allergies in Childhood questionnaire was conducted when the offspring were 2 years old. Multivariate Poisson regression adjusting for maternal baseline demographics was used to elucidate the association between maternal vegetable intake and the incidence of wheeze in the offspring.

RESULTS

Among 310 singletons, 82 (26.5%) experienced wheeze at 2 years of age. Women with the highest intake of cruciferous, and folate-rich vegetables during early pregnancy reported a significantly lower prevalence of wheeze in their child at 2 years of age in comparison with those who reported the lowest intake (adjusted risk ratio: 0.48 and 0.47, 95% confidence interval: 0.26-0.89, and 0.25-0.87, respectively). In trend analysis, a higher maternal intake of cruciferous, folate-rich vegetables, and total vegetables during early pregnancy was less likely to be associated with wheeze in the offspring at 2 years old (p for trend: 0.038, <0.001, and 0.028, respectively). Maternal vegetable intake during mid to late pregnancy was not associated with wheeze in the offspring.

CONCLUSIONS

Maternal vegetable intake during early pregnancy may have a protective effect against asthma in offspring at 2 years of age.

Influence of the Mediterranean diet during pregnancy in the development of wheezing and eczema in infants in Pamplona, Spain

BACKGROUND

This study examined the relationship between different food groups and the adherence to a Mediterranean diet during pregnancy and the risk of wheezing and eczema in children aged 12-15 months.

METHODS

The study involves 1087 Spanish infants from the International Study of Wheezing in Infants (Estudio Internacional de Sibilancias en Lactantes, EISL). The study of the association of the different food consumption and Mediterranean diet with wheezing, recurrent wheezing and eczema was performed using different models of unconditional logistic regression to obtain adjusted prevalence odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

No association was found between a good adherence to the Mediterranean diet during pregnancy and the development of wheezing (p=0.372), recurrent wheezing (p=0.118) and eczema (p=0.315). The consumption once or twice a week of white fish (OR: 1.95[1.01-3.75]), cooked potatoes (OR: 1.75[1.22-2.51]) and industrial pastry (OR: 1.59[1.13-2.24]), and the consumption more than three times a week of industrial pastry (OR: 1.47 [1.01-2.13]) during pregnancy increases the risk of "wheezing" at 12 months. Instead, high fruit consumption during the pregnancy has a protective effect against "wheezing" in 12-month-old infants (OR: 0.44 [0.20-0.99]). No statistically significant differences were observed between food intake during pregnancy and "recurrent wheezing". No statistically significant differences were observed between the consumption of any food during pregnancy and the presence of eczema at 12 months.

CONCLUSIONS

The present study showed that the consumption of Mediterranean diet during pregnancy did not have a protective effect for wheezing, recurrent wheezing or eczema.

Diet and Asthma: Is It Time to Adapt Our Message?

Asthma is a chronic respiratory disorder which is associated with airway inflammation. Environmental factors, in association with genetic susceptibility, play a critical role in asthma pathophysiology. Inhaled allergens, smoke exposure, indoor and outdoor air pollution are common triggers of asthma symptoms. Although the role of diet has clearly established mechanisms in diseases such as cardiovascular disease, type 2 diabetes, and cancer, it is not commonly identified as a causal factor in asthma. However, some dietary patterns, such as the Western diet, which includes a high intake of refined grains, processed and red meats, and desserts, have pro-inflammatory effects. On the contrary, the Mediterranean diet, with high intake of fruits and vegetables has anti-inflammatory properties. The influence of food on asthma outcomes is of growing interest, but dietary habits of asthma patients are not commonly investigated in clinical practice. In this review, we focus on the impact of diet on asthma risk and asthma control. We also detail the influence of diet on obese patients with asthma.

Effect of Maternal Dietary Patterns during Pregnancy on Self-Reported Allergic Diseases in the First 3 Years of Life: Results from the GUSTO Study

BACKGROUND

Maternal diet during pregnancy has been suggested to be an important early-life exposure that influences immune tolerance and the development of allergic diseases in offspring.

METHODS

We examined the relationship between maternal dietary patterns assessed using 24-h recalls and food diaries at 26-28 weeks of pregnancy and the subsequent development of allergic outcomes in the offspring in the Growing Up in Singapore towards Healthy Outcomes (GUSTO) birth cohort. Exploratory factor analysis was used to characterize maternal dietary patterns during pregnancy. During repeated visits in the first 36 months of life, questionnaires were administered to ascertain allergic symptoms, namely, eczema, rhinitis, and wheeze. At ages 18 and 36 months, we administered skin-prick testing to inhalant and food allergens.

RESULTS

Of the 3 maternal dietary patterns that emerged, the seafood and noodles pattern was associated with a reduced risk of developing allergen sensitization at both 18 months (odds ratio [95% confidence interval]: 0.7 [0.5-0.9]) and 36 months (0.7 [0.6-0.9]) after adjustment for a family history of allergy, and ethnicity, sex, and maternal education levels. No associations between the patterns vegetables, fruit, and white rice or pasta, cheese, and processed meat were observed with any of the allergic outcomes in the first 18 and 36 months of life.

CONCLUSION

Maternal diet during pregnancy can influence the subsequent development of allergic outcomes in offspring.

Effects of Fruit and Vegetable Consumption on Risk of Asthma, Wheezing and Immune Responses: A Systematic Review and Meta-Analysis

Evidence suggests that reduced intake of fruit and vegetables may play a critical role in the development of asthma and allergies. The present review aimed to summarize the evidence for the association between fruit and vegetable intake, risk of asthma/wheeze and immune responses. Databases including PubMed, Cochrane, CINAHL and EMBASE were searched up to June 2016. Studies that investigated the effects of fruit and vegetable intake on risk of asthma/wheeze and immune responses were considered eligible (n = 58). Studies used cross-sectional (n = 30), cohort (n = 13), case-control (n = 8) and experimental (n = 7) designs. Most of the studies (n = 30) reported beneficial associations of fruit and vegetable consumption with risk of asthma and/or respiratory function, while eight studies found no significant relationship. Some studies (n = 20) reported mixed results, as they found a negative association between fruit only or vegetable only, and asthma. In addition, the meta-analyses in both adults and children showed inverse associations between fruit intake and risk of prevalent wheeze and asthma severity (p < 0.05). Likewise, vegetable intake was negatively associated with risk of prevalent asthma (p < 0.05). Seven studies examined immune responses in relation to fruit and vegetable intake in asthma, with n = 6 showing a protective effect against either systemic or airway inflammation. Fruit and vegetable consumption appears to be protective against asthma.

Fish intake during pregnancy or infancy and allergic outcomes in children: A systematic review and meta-analysis

It has been suggested that n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) have anti-inflammatory properties and may reduce the risk of allergic disease. Fish is a great source of n-3 LC-PUFAs. However, the effect of fish on allergic disease remains controversial. PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) and prospective cohort studies regarding the effect of fish intake during pregnancy or infancy on allergic outcomes in children. The outcomes of interest were atopy, eczema, allergic rhinitis, wheeze, asthma, and food allergy. One RCT and 17 publications from 13 prospective cohort studies were included for maternal fish intake during pregnancy, and eight publications from five prospective cohort studies for fish intake in infancy. Pooled analysis suggested that maternal fish intake during pregnancy was not associated with lower risk of any allergic outcome, both in RCT and observational studies. Consumption of fish during the first year of life reduced the risk of eczema (RR 0.61; 95% CI 0.47, 0.80; p = 0.0003; I²  = 68%) and allergic rhinitis (RR 0.54; 95% CI 0.36, 0.81; p = 0.003; I²  = 74%). Current evidence indicates that fish intake in infancy could reduce the risk of eczema and allergic rhinitis in children, whereas maternal fish intake during pregnancy does not affect any atopic outcome. The intake of fish per se in infancy, not specially n-3 LC-PUFAs, may have an allergy protective effect. High-quality and adequately powered RCTs are warranted to confirm this.

Regulatory T Cells in Allergy and Asthma

The immune system's correct functioning requires a sophisticated balance between responses to continuous microbial challenges and tolerance to harmless antigens, such as self-antigens, food antigens, commensal microbes, allergens, etc. When this equilibrium is altered, it can lead to inflammatory pathologies, tumor growth, autoimmune disorders, and allergy/asthma. The objective of this review is to show the existing data on the importance of regulatory T cells (Tregs) on this balance and to underline how intrauterine and postnatal environmental exposures influence the maturation of the immune system in humans. Genetic and environmental factors during embryo development and/or early life will result in a proper or, conversely, inadequate immune maturation with either beneficial or deleterious effects on health. We have focused herein on Tregs as a reflection of the maturity of the immune system. We explain the types, origins, and the mechanisms of action of these cells, discussing their role in allergy and asthma predisposition. Understanding the importance of Tregs in counteracting dysregulated immunity would provide approaches to diminish asthma and other related diseases in infants.

Polyunsaturated fatty acid supplementation in infancy for the prevention of allergy

BACKGROUND

Early dietary intakes may influence the development of allergic disease. It is important to determine if dietary polyunsaturated fatty acids (PUFAs) given as supplements or added to infant formula prevent the development of allergy.

OBJECTIVES

To determine the effect of higher PUFA intake during infancy to prevent allergic disease.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 9), MEDLINE (1966 to 14 September 2015), EMBASE (1980 to 14 September 2015) and CINAHL (1982 to 14 September 2015). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials that compared the use of a PUFA with no PUFA in infants for the prevention of allergy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed trial quality and extracted data from the included studies. We used fixed-effect analyses. The treatment effects were expressed as risk ratio (RR) with 95% confidence intervals (CI). We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

The search found 17 studies that assessed the effect of higher versus lower intake of PUFAs on allergic outcomes in infants. Only nine studies enrolling 2704 infants reported allergy outcomes that could be used in meta-analyses. Of these, there were methodological concerns for eight.In infants up to two years of age, meta-analyses found no difference in incidence of all allergy (1 study, 323 infants; RR 0.96, 95% CI 0.73 to 1.26; risk difference (RD) -0.02, 95% CI -0.12 to 0.09; heterogeneity not applicable), asthma (3 studies, 1162 infants; RR 1.04, 95% CI 0.80 to 1.35, I2 = 0%; RD 0.01, 95% CI -0.04 to 0.05, I2 = 0%), dermatitis/eczema (7 studies, 1906 infants; RR 0.93, 95% CI 0.82 to 1.06, I2 = 0%; RD -0.02, 95% CI -0.06 to 0.02, I2 = 0%) or food allergy (3 studies, 915 infants; RR 0.81, 95% CI 0.56 to 1.19, I2 = 63%; RD -0.02, 95% CI -0.06 to 0.02, I2 = 74%). There was a reduction in allergic rhinitis (2 studies, 594 infants; RR 0.47, 95% CI 0.23 to 0.96, I2 = 6%; RD -0.04, 95% CI -0.08 to -0.00, I2 = 54%; number needed to treat for an additional beneficial outcome (NNTB) 25, 95% CI 13 to ∞).In children aged two to five years, meta-analysis found no difference in incidence of all allergic disease (2 studies, 154 infants; RR 0.69, 95% CI 0.47 to 1.02, I2 = 43%; RD -0.16, 95% CI -0.31 to -0.00, I2 = 63%; NNTB 6, 95% CI 3 to ∞), asthma (1 study, 89 infants; RR 0.45, 95% CI 0.20 to 1.02; RD -0.20, 95% CI -0.37 to -0.02; heterogeneity not applicable; NNTB 5, 95% CI 3 to 50), dermatitis/eczema (2 studies, 154 infants; RR 0.65, 95% CI 0.34 to 1.24, I2 = 0%; RD -0.09 95% CI -0.22 to 0.04, I2 = 24%) or food allergy (1 study, 65 infants; RR 2.27, 95% CI 0.25 to 20.68; RD 0.05, 95% CI -0.07 to 0.16; heterogeneity not applicable).In children aged two to five years, meta-analysis found no difference in prevalence of all allergic disease (2 studies, 633 infants; RR 0.98, 95% CI 0.81 to 1.19, I2 = 36%; RD -0.01, 95% CI -0.08 to 0.07, I2 = 0%), asthma (2 studies, 635 infants; RR 1.12, 95% CI 0.82 to 1.53, I2 = 0%; RD 0.02, 95% CI -0.04 to 0.09, I2 = 0%), dermatitis/eczema (2 studies, 635 infants; RR 0.81, 95% CI 0.59 to 1.09, I2 = 0%; RD -0.04 95% CI -0.11 to 0.02, I2 = 0%), allergic rhinitis (2 studies, 635 infants; RR 1.02, 95% CI 0.83 to 1.25, I2 = 0%; RD 0.01, 95% CI -0.06 to 0.08, I2 = 0%) or food allergy (1 study, 119 infants; RR 0.27, 95% CI 0.06 to 1.19; RD -0.10, 95% CI -0.20 to -0.00; heterogeneity not applicable; NNTB 10, 95% CI 5 to ∞).

AUTHORS' CONCLUSIONS

There is no evidence that PUFA supplementation in infancy has an effect on infant or childhood allergy, asthma, dermatitis/eczema or food allergy. However, the quality of evidence was very low. There was insufficient evidence to determine an effect on allergic rhinitis.

Prenatal Fish Oil Supplementation and Allergy: 6-Year Follow-up of a Randomized Controlled Trial

BACKGROUND AND OBJECTIVE

Evidence from randomized controlled trials in early infancy suggest that prenatal supplementation with Ω-3 (n-3) long-chain polyunsaturated fatty acids (LCPUFA) reduces the incidence of allergic disease characterized by an immunoglobulin E (IgE) response. We aimed to determine whether protective effects were evident in the 6-year-old offspring of women supplemented with n-3 rich fish oil during pregnancy.

METHODS

Six-year follow-up of children (n = 706) with a family history of allergic disease from the Docosahexaenoic Acid to Optimize Mother Infant Outcome (DOMInO) trial. Women were randomly allocated to receive n-3 LCPUFA-rich fish oil capsules (800 mg/d docosahexaenoic acid DHA and 100mg/d eicosapentaenoic acid) or vegetable oil capsules (without n-3 LCPUFA). Allergic disease symptoms including eczema, wheeze, rhinitis, and rhino-conjunctivitis, were assessed using the International Study of Asthma and Allergies in Childhood questionnaire and sensitization to allergens was measured by skin prick test.

RESULTS

There was no difference in the percentage of children with any IgE-associated allergic disease between the n-3 LCPUFA and control groups (116/367 [31.5%] vs 106/336 [31.5%]; adjusted relative risk, 1.04; 95% confidence interval, 0.82-1.33; P = .73). There was a reduction in the percentage of children sensitized to house dust mite Dermatophagoides farinae (49/367 [13.4%] vs 68/336 [20.3%]; adjusted relative risk, 0.67, 95% confidence interval, 0.44-1.00; P = .0495).

CONCLUSIONS

Prenatal n-3 LCPUFA supplementation did not reduce IgE-associated allergic disease at 6 years of age. Secondary outcomes were suggestive of a protective effect of the intervention on the incidence of D. farinae sensitization.

Relationship between respiratory and food allergy and evaluation of preventive measures

Food allergy and respiratory allergy are two frequently associated diseases and with an increasing prevalence. Several reports show the presence of respiratory symptoms in patients with food allergy, while certain foods may be related to the development or exacerbation of allergic rhinitis and asthma. The present update focuses on this relationship, revealing a pathogenic and clinical association between food and respiratory allergy. This association is even more intense when the food hypersensitivity is persistent or starts in the early years of life. Food allergy usually precedes respiratory allergy and may be a risk factor for allergic rhinitis and asthma, becoming a relevant clinical marker for severe atopic asthma. Furthermore, the presence of co-existing asthma may enhance life-threatening symptoms occurring during a food allergic reaction. Recommendations for dietary restrictions during pregnancy and breastfeeding to prevent the development of respiratory allergy are controversial and not supported by consistent scientific data. Current recommendations from medical societies propose exclusive breastfeeding during the first four months of life, with the introduction of solid food in the fourth to the seventh month period of life. A delayed introduction of solid food after this period may increase the risk of developing subsequent allergic conditions. Further studies are encouraged to avoid unjustified recommendations involving useless dietary restrictions.

Maternal diet during pregnancy and lactation and cow's milk allergy in offspring

BACKGROUND/OBJECTIVES

Diet during pregnancy and lactation may have a role in the development of allergic diseases. There are few human studies on the topic, especially focusing on food allergies. We sought to study the associations between maternal diet during pregnancy and lactation and cow's milk allergy (CMA) in offspring.

SUBJECTS/METHODS

A population-based birth cohort with human leukocyte antigen-conferred susceptibility to type 1 diabetes was recruited in Finland between 1997 and 2004 (n=6288). Maternal diet during pregnancy and lactation was assessed by a validated, 181-item semi-quantitative food frequency questionnaire. Register-based information on diagnosed CMA was obtained from the Social Insurance Institution and completed with parental reports. The associations between maternal food consumption and CMA were assessed using logistic regression, comparing the highest and the lowest quarters to the middle half of consumption.

RESULTS

Consumption of milk products in the highest quarter during pregnancy was associated with a lower risk of CMA in offspring (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.37-0.86; P<0.01). When stratified by maternal allergic rhinitis and asthma, there was evidence of an inverse association between high use of milk products and CMA in offspring of non-allergic mothers (OR 0.30, 95% CI 0.13-0.69, P<0.001). Cord blood IgA correlated positively with the consumption of milk products during pregnancy, indicating exposure to CMA and activation of antigen-specific immunity in the infant during pregnancy.

CONCLUSIONS

High maternal consumption of milk products during pregnancy may protect children from developing CMA, especially in offspring of non-allergic mothers.

Omega-3 long-chain PUFA intake during pregnancy and allergic disease outcomes in the offspring: a systematic review and meta-analysis of observational studies and randomized controlled trials

BACKGROUND

There is some evidence that increased maternal intake of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFAs) during pregnancy may reduce the incidence of immunoglobulin E (IgE)-mediated allergic disease.

OBJECTIVE

We aimed to evaluate prenatal n-3 LC-PUFA dietary exposure in observational studies and n-3 LC-PUFA supplementation in randomized controlled trials (RCTs) on outcomes of IgE-mediated allergic disease.

DESIGN

We conducted searches of the Cochrane Central Register of Controlled Trials, PubMed, Ovid MEDLINE, EMBASE, CINAHL, SCOPUS, and Web of Science to 30 July 2015. We included prospective cohort studies that showed an association between maternal fish or n-3 LC-PUFA intake during pregnancy and RCTs with a prenatal intervention to modify maternal n-3 LC-PUFA intake and outcomes of allergic disease (eczema, rhino-conjunctivitis, asthma) or sensitization in the offspring.

RESULTS

A total of 13 publications from 10 prospective cohort studies and 7 publications representing 5 unique RCTs were included. Three RCTs were combined in a meta-analysis for selected outcomes. Nine of 13 observational study publications and 5 of 7 publications from RCTs found a protective association between increased prenatal n-3 LC-PUFA or fish intake and incidence of allergic disease symptoms in the child. Meta-analysis was limited because of the heterogeneity of the RCTs. Pooled results showed a significant reduction in the incidence of "atopic eczema," "any positive SPT [skin-prick test]," "sensitization to egg," and "sensitization to any food" in the first 12 mo of life [RRs (95% CIs): 0.53 (0.35, 0.81), P = 0.004; 0.68 (0.52-0.89), P = 0.006; 0.55 (0.39-0.76), P = 0.0004; and 0.59 (0.46, 0.76), P < 0.0001, respectively].

CONCLUSIONS

Our systematic review and meta-analysis was suggestive of benefits of increased n-3 LC-PUFAs in the maternal diet and outcomes of childhood allergic disease. However, due to the inconsistency in results, the hypothesis linking maternal n-3 LC-PUFA intake to childhood allergic disease cannot unequivocally be confirmed or rejected.

Taking the leap earlier: the timing of tolerance

PURPOSE OF REVIEW

The paradigm for the primary prevention of peanut allergy was, until recently, strict avoidance of peanut during pregnancy, infancy, and early childhood. However, in countries that had these dietary guidelines, the prevalence of peanut allergy greatly increased in contrast to low prevalence rates of peanut allergy in countries where infant diets included peanut at an early age, suggesting the hypothesis that early introduction of peanut is superior to delayed introduction of peanut as a strategy for the primary prevention of food allergy. This review examines recent high-quality studies that support this hypothesis.

RECENT FINDINGS

Publication of the Learning Early about Allergy to Peanut interventional trial showed that 17% of children avoiding peanut until 5 years of age developed peanut allergy compared with 3% of children who started eating peanut at ages of 4-11 months. Two birth cohort studies demonstrated that high maternal consumption of peanut during the pregnancy period reduced the risk of peanut allergy in offspring by 50-75%.

SUMMARY

Recent studies indicate that early introduction of peanut enhances the development of tolerance to peanut, reducing the risk of childhood peanut allergy.

Maternal nutrition during pregnancy and risk of asthma, wheeze, and atopic diseases during childhood: a systematic review and meta-analysis

BACKGROUND

Epidemiologic studies suggest a relationship between maternal nutrition during pregnancy and the occurrence of asthma and atopic conditions during childhood. However, individual study results are conflicting. The objective of this meta-analysis was to critically examine the current evidence for an association between nutrition (dietary patterns, food groups, vitamins, or oligo-elements) ingestion during pregnancy and asthma, wheeze, or atopic conditions in childhood.

METHODS

The inclusion criteria were as follows: (i) systematic recording of diet during the gestational period and (ii) documentation of asthma, wheezing, eczema, or other atopic disease in the offspring. The primary outcomes were prevalence of asthma or wheeze among the offspring during childhood; and secondary outcomes were prevalence of eczema, allergic rhinitis, or other atopic conditions.

RESULTS

We found 120 titles, abstracts, and citations, and 32 studies (29 cohorts) were included in this analysis. Data on vitamins, oligo-elements, food groups, and dietary patterns during pregnancy were collected. A meta-analysis revealed that higher maternal intake of vitamin D [odds ratio (OR) = 0.58, 95% confidence interval (CI) = 0.38-0.88], vitamin E (OR = 0.6, 95% CI = 0.46-0.78), and zinc (OR = 0.62, 95% CI = 0.40-0.97) was associated with lower odds of wheeze during childhood. However, none of these or other nutrients was consistently associated with asthma per se or other atopic conditions.

CONCLUSIONS

Current evidence suggests a protective effect of maternal intake of each of three vitamins or nutrients (vitamin D, vitamin E, and zinc) against childhood wheeze but is inconclusive for an effect on asthma or other atopic conditions.

Update on epigenetics in allergic disease

Chronic inflammatory diseases, including allergies and asthma, are the result of complex gene-environment interactions. One of the most challenging questions in this regard relates to the biochemical mechanism of how exogenous environmental trigger factors modulate and modify gene expression, subsequently leading to the development of chronic inflammatory conditions. Epigenetics comprises the umbrella of biochemical reactions and mechanisms, such as DNA methylation and chromatin modifications on histones and other structures. Recently, several lifestyle and environmental factors have been investigated in terms of such biochemical interactions with the gene expression-regulating machinery: allergens; microbes and microbial compounds; dietary factors, including vitamin B12, folic acid, and fish oil; obesity; and stress. This article aims to update recent developments in this context with an emphasis on allergy and asthma research.

Early-life origins of chronic respiratory diseases: understanding and promoting healthy ageing

Chronic obstructive respiratory disorders such as asthma and chronic obstructive pulmonary disease often originate early in life. In addition to a genetic predisposition, prenatal and early-life environmental exposures have a persistent impact on respiratory health. Acting during a critical phase of lung development, these factors may change lung structure and metabolism, and may induce maladaptive responses to harmful agents, which will affect the whole lifespan. Some environmental factors, such as exposure to cigarette smoke, type of childbirth and diet, may be modifiable, but it is more difficult to influence other factors, such as preterm birth and early exposure to viruses or allergens. Here, we bring together recent literature to analyse the critical aspects involved in the early stages of lung development, going back to prenatal and perinatal events, and we discuss the mechanisms by which noxious factors encountered early on may have a lifelong impact on respiratory health. We briefly comment on the need for early disease biomarkers and on the possible role of "-omic" technologies in identifying risk profiles predictive of chronic respiratory conditions. Such profiles could guide the ideation of effective preventive strategies and/or targeted early lifestyle or therapeutic interventions.

Maternal consumption of dairy products, calcium, and vitamin D during pregnancy and infantile allergic disorders

BACKGROUND

Epidemiologic evidence of the association between maternal intake of dairy foods, calcium, and vitamin D during pregnancy and childhood allergic disorders is inconclusive.

OBJECTIVE

To examine the association between maternal intake of dairy foods, calcium, and vitamin D during pregnancy and childhood allergic disorders in Japanese children aged 23 to 29 months.

METHODS

Study participants were 1,354 mother-child pairs. Maternal intake during pregnancy was assessed with a validated diet history questionnaire administered between April 2007 and March 2008. Wheeze and eczema, defined according to criteria of the International Study of Asthma and Allergies in Childhood, and physician-diagnosed asthma and atopic eczema were assessed via a questionnaire completed by mothers.

RESULTS

Higher maternal intake of total dairy products during pregnancy was significantly associated with a reduced risk of infantile eczema (adjusted odds ratio [OR] between extreme quartiles, 0.64; 95% confidence interval [CI], 0.42-0.98). Higher maternal intake of cheese during pregnancy was significantly related to a reduced risk of physician-diagnosed infantile asthma (adjusted OR between extreme quartiles, 0.44; 95% CI, 0.18-0.97). Maternal intake levels of yogurt and calcium during pregnancy were significantly inversely associated with physician-diagnosed infantile atopic eczema (adjusted ORs between extreme quartiles, 0.49 and 0.34; 95% CI, 0.20-1.16 and 0.12-0.84; P for trend = .01 and .03, respectively). Maternal intake of vitamin D during pregnancy was significantly positively associated with infantile eczema (adjusted OR between extreme quartiles, 1.63; 95% CI, 1.07-2.51).

CONCLUSION

Higher maternal intake of total dairy products, cheese, yogurt, and calcium during pregnancy may reduce the risk of infantile eczema, physician-diagnosed asthma, physician-diagnosed atopic eczema, and physician-diagnosed atopic eczema, respectively. Higher maternal intake of vitamin D during pregnancy may increase the risk of infantile eczema.

Fruit and vegetable intake and risk of wheezing and asthma: a systematic review and meta-analysis

Major bibliographic databases were searched for studies examining the relationship between fruit and vegetable consumption and the risk of wheezing and asthma. Random-effects models were used to pool study results. Subgroup analyses were conducted by fruit and vegetable categories, study design, and age group. Twelve cohorts, 4 population-based case-control studies, and 26 cross-sectional studies published between January 1990 and July 2013 were identified. For the meta-analysis of adults and children, the relative risk (RR) and confidence intervals (CI) when comparing the highest intake group with the lowest intake group were 0.78 (95%CI, 0.70-0.87) for fruit and 0.86 (95%CI, 0.75-0.98) for vegetables. High intake of fruit and vegetables (RR = 0.76; 95%CI, 0.68-0.86 and RR = 0.83; 95%CI, 0.72-0.96) reduced the risk of childhood wheezing. Total intake of fruit and vegetables had a negative association with risk of asthma in adults and children (RR = 0.54; 95%CI, 0.41-0.69). Consuming fruit and vegetables during pregnancy had no association with the risk of asthma in offspring. High intake of fruit and vegetables may reduce the risk of asthma and wheezing in adults and children.

Peanut, milk, and wheat intake during pregnancy is associated with reduced allergy and asthma in children

BACKGROUND

Maternal diet during pregnancy may affect childhood allergy and asthma.

OBJECTIVE

We sought to examine the associations between maternal intake of common childhood food allergens during early pregnancy and childhood allergy and asthma.

METHODS

We studied 1277 mother-child pairs from a US prebirth cohort unselected for any disease. Using food frequency questionnaires administered during the first and second trimesters, we assessed maternal intake of common childhood food allergens during pregnancy. In mid-childhood (mean age, 7.9 years), we assessed food allergy, asthma, allergic rhinitis, and atopic dermatitis by questionnaire and serum-specific IgE levels. We examined the associations between maternal diet during pregnancy and childhood allergy and asthma. We also examined the cross-sectional associations between specific food allergies, asthma, and atopic conditions in mid-childhood.

RESULTS

Food allergy was common (5.6%) in mid-childhood, as was sensitization to at least 1 food allergen (28.0%). Higher maternal peanut intake (each additional z score) during the first trimester was associated with 47% reduced odds of peanut allergic reaction (odds ratio [OR], 0.53; 95% CI, 0.30-0.94). Higher milk intake during the first trimester was associated with reduced asthma (OR, 0.83; 95% CI, 0.69-0.99) and allergic rhinitis (OR, 0.85; 95% CI, 0.74-0.97). Higher maternal wheat intake during the second trimester was associated with reduced atopic dermatitis (OR, 0.64; 95% CI, 0.46-0.90). Peanut, wheat, and soy allergy were each cross-sectionally associated with increased childhood asthma, atopic dermatitis, and allergic rhinitis (ORs, 3.6 to 8.1).

CONCLUSION

Higher maternal intake of peanut, milk, and wheat during early pregnancy was associated with reduced odds of mid-childhood allergy and asthma.

Prenatal adverse life events increase the risk for atopic diseases in children, which is enhanced in the absence of a maternal atopic predisposition

BACKGROUND

There is evidence to suggest an association between prenatal maternal stress and the development of asthma or other atopic diseases in offspring. Yet, insights on the lasting effect of multiple, common prenatal stressors are rare, and the effects of prenatal timing are poorly understood. Further, it remains elusive if prenatal life events modify the risk for atopic diseases in the context of a parental predisposition to atopy.

OBJECTIVE

We tested whether women's experiences of common, adverse life events during the first or second half of pregnancy predicted the risk of developing atopic diseases in their children and whether a reported parental atopic disease moderated this association.

METHODS

We calculated the odds of a child developing asthma, eczema, and/or allergic rhinitis at ages 6 or 14 years, depending on maternal prenatal exposure to negative life events in a sample of 1587 children from the Western Australian Pregnancy Cohort (Raine) Study by using multivariable logistic regression.

RESULTS

We observed that the likelihood of asthma and eczema at age 14 years was significantly increased in children of mothers who had experienced adverse life events during the second half of gestation (1 life event: adjusted odds ratio for asthma, 2.08 [95% CI, 1.22-3.54]). A stronger increase in the odds to develop asthma upon prenatal life events was present in children of mothers without asthma compared with mothers with asthma.

CONCLUSIONS

Maternal adverse life events during the second half of gestation are linked to an increased risk for the development of atopic disorders, asthma, and eczema, in the case of asthma, particularly in the absence of a maternal asthma.

Does maternal diet during pregnancy and lactation affect outcomes in offspring? A systematic review of food-based approaches

OBJECTIVES

The aim of this study was to investigate the relationship between maternal diet during pregnancy and lactation and development of atopic disorders in childhood.

METHODS

We included studies published up to August 2011 that assessed food-based maternal dietary interventions or that examined associations between maternal dietary intake during pregnancy and/or lactation and allergic outcomes (eczema, asthma, hay fever, and sensitization) in their children.

RESULTS

We included 42 studies (>40 000 children): 11 intervention studies (including 7 randomized control trials), 26 prospective cohort studies, 4 retrospective cohort studies, and 1 case-control study. In the randomized control trials, no significant difference was noted overall in the prevalence of eczema and asthma in the offspring of women on diets free from common food allergens during pregnancy. The prospective cohorts investigated a large number of potential associations, but reported few significant associations between maternal dietary intake and development of allergy. Maternal diets rich in fruits and vegetables, fish, and foods containing vitamin D and Mediterranean dietary patterns were among the few consistent associations with lower risk for allergic disease in their children. Foods associated with higher risk included vegetable oils and margarine, nuts, and fast food.

CONCLUSION

This review did not find widespread or consistent links between mothers' dietary intake and atopic outcomes in their children. However, maternal consumption of Mediterranean dietary patterns, diets rich in fruits and vegetables, fish, and vitamin D-containing foods were suggestive of benefit, requiring further evaluation.

Fish and fish oil intake in relation to risk of asthma: a systematic review and meta-analysis

Although laboratory studies suggest that long-chain n-3 polyunsaturated fatty acids (LCn3PUFAs) may reduce risk of asthma, epidemiological data remain controversial and inconclusive. We quantitatively reviewed the epidemiological studies published through December 2012 in PubMed and EMBASE by using a fixed-effects or random-effects model. Eleven studies, comprised of 99,093 individuals (3,226 cases), were included in the final dataset. Of them, 7 studies examined associations between intake of fish or LCn3PUFA and risk of asthma: 4 studies in children (996 cases from 12,481 children) and 3 in adults (1,311 cases from 82,553 individuals). Two studies (69 cases from 276 infants) investigated LCn3PUFA levels in mothers' milk, and two studies assessed maternal fish consumption (786 cases from 2,832 individuals) during lactation and/or plasma LCn3PUFA levels during pregnancy (64 cases from 951 infants) in relation to offspring's asthma. The pooled relative risk of child asthma were 0.76 (95% CI, 0.61-0.94) for fish consumption and 0.71 (95% CI, 0.52-0.96) for LCn3PUFA intake. No statistically significant association was found in studies among adults. Epidemiological data to date indicate that fish or LCn3PUFA intake may be beneficial to prevent asthma in children. Further studies are needed to establish causal inference and to elucidate the potential mechanisms.

Mediterranean diet adherence during pregnancy and risk of wheeze and eczema in the first year of life: INMA (Spain) and RHEA (Greece) mother-child cohort studies

Maternal diet during pregnancy might influence the development of childhood allergic disorders. The aim of the present study was to evaluate the impact of Mediterranean diet (MD) adherence during pregnancy on wheeze and eczema in the first year of life in two population-based mother-child cohorts in Spain and Greece. We studied 1771 mother-newborn pairs from the Spanish multi-centre 'INMA' (INfancia y Medio Ambiente) study (Gipuzkoa, Sabadell and Valencia) and 745 pairs from the 'RHEA' study in Crete, Greece. The symptoms of wheeze and eczema were based on the criteria of the International Study of Asthma and Allergies in Childhood. Maternal diet during pregnancy was assessed by FFQ and MD adherence was evaluated through an a priori score. Multivariate log-binomial regression models were used to adjust for several confounders in each cohort and summary estimates were obtained by a meta-analysis. MD adherence was not associated with the risk of wheeze and eczema in any cohort, and similar results were identified in the meta-analysis approach. High meat intake (relative risk (RR) 1·22, 95 % CI 1·00, 1·49) and 'processed' meat intake (RR 1·18, 95 % CI 1·02, 1·37) during pregnancy were associated with an increased risk of wheeze in the first year of life, while a high intake of dairy products was significantly associated with a decreased risk of infantile wheeze (RR 0·83, 95 % CI 0·72, 0·96). The results of the present study show that high meat intake during pregnancy may increase the risk of wheeze in the first year of life, while a high intake of dairy products may decrease it.