Atopy, eczema and breast milk fatty acids in a high-risk cohort of children followed from birth to 5 yr

Human milk polyunsaturated fatty acids are related to neurodevelopmental, anthropometric, and allergic outcomes in early life: a systematic review

Polyunsaturated fatty acids are critically important for newborn nutrition and in the trajectory of growth and developmental processes throughout early life. This systematic review (PROSPERO ID: CRD42023400059) critically analyzes literature pertaining to how omega-3 and omega-6 fatty acids in human milk are related to health outcomes in early life. Literature selected for the review were published between 2005 and 2020 and included assessments in healthy term children between 0 and 5 years of age. The studies reported the relation between human milk fatty acids docosahexaenoic acid (C22:6n-3, DHA), eicosapentaenoic acid (C20:5n-3, EPA), alpha-linolenic acid (C18:3n-3, ALA), arachidonic acid (C20:4n-6, AA), and linoleic acid (C18:2n-6, LA) with three domains of health outcomes: neurodevelopment, body composition, and allergy, skin & eczema. Results from the 21 studies consistently suggested better health outcomes across the three domains for infants consuming milk with higher concentrations of total n-3, DHA, EPA, and ALA. Negative health outcomes across the three domains were associated with higher levels of total n-6, AA, and LA in milk. N-3 and n-6 content of milk were related to neurodevelopmental, body composition, and allergy, skin & eczema outcomes with moderate certainty. Maternal diet impacting milk fatty acid content and fatty acid desaturase genotype modifying physiologic responses to fatty acid intake were prominent gaps identified in the review using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies and GRADE approach. This research study can inform baby nutrition product development, and fatty acid intake recommendations or dietary interventions for mothers and children.

Sex-specific associations of human milk long-chain polyunsaturated fatty acids and infant allergic conditions

BACKGROUND

Polyunsaturated fatty acids (PUFAs) may influence immune development. We examined the association of PUFAs in human milk with food sensitization and atopic dermatitis among breastfed infants.

METHODS

In a selected subgroup of 1109 mother-infant dyads from the CHILD Cohort Study, human milk was analyzed by gas-liquid chromatography to quantify PUFAs including arachidonic acid (ARA) and docosahexaenoic acid (DHA). At 1 year of age, food sensitization was determined by skin-prick testing for egg, peanut, cow's milk, and soybean, and atopic dermatitis was diagnosed by pediatricians. Logistic regression analyses controlled for breastfeeding exclusivity, family history of atopy, and other potential confounders.

RESULTS

Overall, 184 infants (17%) were sensitized to one or more food allergens and 160 (14%) had atopic dermatitis. Sex-specific associations were observed between these conditions and milk PUFAs. Girls receiving human milk with lower proportions of DHA had lower odds of food sensitization (aOR 0.35; 95% CI 0.12, 0.99 for lowest vs highest quintile), and a clear dose-dependent association was observed for the ARA/DHA ratio (aOR 2.98; 95% CI 1.10, 8.06 for lowest vs highest quintile). These associations were not seen in boys. Similar sex-specific tendencies were observed for atopic dermatitis.

CONCLUSIONS

Human milk PUFA proportions and their ratios are associated with infant atopic conditions in a sex-specific manner. In female infants, a higher ratio of ARA/DHA may reduce the risk of food sensitization and atopic dermatitis. Further research is needed to determine the underlying mechanisms and clinical relevance of this sex-specific association.

The Influence of Dietary Fatty Acids on Immune Responses

Diet-derived fatty acids (FAs) are essential sources of energy and fundamental structural components of cells. They also play important roles in the modulation of immune responses in health and disease. Saturated and unsaturated FAs influence the effector and regulatory functions of innate and adaptive immune cells by changing membrane composition and fluidity and by acting through specific receptors. Impaired balance of saturated/unsaturated FAs, as well as n-6/n-3 polyunsaturated FAs has significant consequences on immune system homeostasis, contributing to the development of many allergic, autoimmune, and metabolic diseases. In this paper, we discuss up-to-date knowledge and the clinical relevance of the influence of dietary FAs on the biology, homeostasis, and functions of epithelial cells, macrophages, dendritic cells, neutrophils, innate lymphoid cells, T cells and B cells. Additionally, we review the effects of dietary FAs on the pathogenesis of many diseases, including asthma, allergic rhinitis, food allergy, atopic dermatitis, rheumatoid arthritis, multiple sclerosis as well as type 1 and 2 diabetes.

EAACI position paper: Influence of dietary fatty acids on asthma, food allergy, and atopic dermatitis

The prevalence of allergic diseases such as allergic rhinitis, asthma, food allergy, and atopic dermatitis has increased dramatically during the last decades, which is associated with altered environmental exposures and lifestyle practices. The purpose of this review was to highlight the potential role for dietary fatty acids, in the prevention and management of these disorders. In addition to their nutritive value, fatty acids have important immunoregulatory effects. Fatty acid-associated biological mechanisms, human epidemiology, and intervention studies are summarized in this review. The influence of genetics and the microbiome on fatty acid metabolism is also discussed. Despite critical gaps in our current knowledge, it is increasingly apparent that dietary intake of fatty acids may influence the development of inflammatory and tolerogenic immune responses. However, the lack of standardized formats (ie, food versus supplement) and standardized doses, and frequently a lack of prestudy serum fatty acid level assessments in clinical studies significantly limit our ability to compare allergy outcomes across studies and to provide clear recommendations at this time. Future studies must address these limitations and individualized medical approaches should consider the inclusion of specific dietary factors for the prevention and management of asthma, food allergy, and atopic dermatitis.

Association of maternal allergy with human milk soluble CD14 and fatty acids, and early childhood atopic dermatitis

BACKGROUND

This study aimed to investigate whether maternal allergy is associated with soluble CD14 (sCD14) and fatty acid composition in different stages of lactation and the onset of atopic dermatitis (AD) in early childhood.

METHODS

In total, 443 mother-child groups (445 children) were enrolled in the Prediction of Allergies in Taiwanese Children birth cohort study. Colostrum and mature milk at 2 months postpartum (2-month HM) were collected from lactating mothers. Information regarding parental allergy histories and physician-diagnosed atopic diseases was obtained using age-specific questionnaires (0-2 years). We compared sCD14 levels and the composition of 30 fatty acids in the colostrum and 2-month HM, respectively, between allergic and non-allergic mothers and between children with and without AD by the age of 2 years.

RESULTS

In total, 185 (41.8%) mothers presented with allergies, and 154 (34.6%) children had physician-diagnosed AD by the age of 2 years. Both in the colostrum and 2-month HM of 289 lactating mothers, sCD14 levels were significantly lower in allergic mothers whose children presented with AD compared with children who did not (P = 0.015 and 0.044, respectively). Among the children with AD who were born to non-allergic mothers, sCD14 levels were lower. However, the result was not statistically significant (P = 0.376 and 0.264, respectively). Our data revealed the lack of associations between fatty acid composition and AD (P > 0.05).

CONCLUSION

Decreased sCD14 levels in the colostrum and 2-month HM were associated with AD at 2 years of age, particularly among children born to mothers with allergies.

Immunologically Active Components in Human Milk and Development of Atopic Disease, With Emphasis on Food Allergy, in the Pediatric Population

Breast-feeding is currently recommended to prevent the development of allergic diseases; however, data are conflicting and mechanisms are unclear. The immunomodulatory composition of human milk is poorly characterized and varies between mothers. We and others have shown that high levels of human milk IgA and certain cytokines and human milk oligosaccharides are associated with protection against food allergy in the infant, but it is unclear whether they are responsible for or simply biomarkers of the vertical transfer of protection. Because human milk has pre- and probiotic properties, the anti-allergy protection afforded by human milk may be due to its control on the developing gut microbiome. In mice, murine milk IgA supports gut homeostasis and shapes the microbiota, which in turn diversifies the intestinal IgA repertoire that reciprocally promotes the diversity of gut microbiome; these mechanisms are poorly understood in humans. In addition, several human milk bioactives are immunostimulatory, which may in part provide protection against allergic diseases. The regulation of immunologically active components in human milk is incompletely understood, although accumulating evidence suggests that IgA and cytokines in human milk reflect maternal exposures. This review summarizes the current literature on human milk components that have been associated with protection against food allergy and related allergic disorders in early childhood and discusses the work relating to regulation of these levels in human milk and possible mechanisms of action.

The impact of human breast milk components on the infant metabolism

BACKGROUND & AIMS

Breastfeeding is beneficial for mothers and infants. Underlying mechanisms and biochemical mediators thus need to be investigated to develop and support improved infant nutrition practices promoting the child health. We analysed the relation between maternal breast milk composition and infant metabolism.

METHODS

196 pairs of mothers and infants from a European research project (PreventCD) were studied. Maternal milk samples collected at month 1 and month 4 after birth were analysed for macronutrient classes, hormone, and fatty acid (FA) content. Phospholipids, acylcarnitines, and amino acids were measured in serum samples of 4-month old infants. Associations between milk components and infant metabolites were analysed with spearman correlation and linear mixed effect models (LME). P-values were corrected for multiple testing (PLME).

RESULTS

Month 1 milk protein content was strongly associated with infant serum lyso-phosphatidylcholine (LPC) 14:0 (PLME = 0.009). Month 1 milk insulin was associated to infant acetylcarnitine (PLME = 0.01). There were no associations between milk protein content and serum amino acids and milk total fat content and serum polar lipids. Middle- and odd-chain FA% in breast milk at both ages were significantly related to serum LPC and sphingomyelins (SM) species in infant serum (all PLME<0.05), while FA% 20:5n-3 and 22:6n-3 percentages were significantly associated to serum LPC 22:6 (PLME = 1.91×10-4/7.93×10-5) in milk only at month 4. Other polyunsaturated fatty acids and hormones in milk showed only weak associations with infant serum metabolites.

CONCLUSIONS

Infant serum LPC are influenced by breast milk FA composition and, intriguingly, milk protein content in early but not late lactation. LPC 14:0, previously found positively associated with obesity risk, was the serum metabolite which was the most strongly associated to milk protein content. Thus, LPC 14:0 might be a key metabolite not only reflecting milk protein intake in infants, but also relating high protein content in milk or infant formula to childhood obesity risk.

Association of breast milk fatty acids with allergic disease outcomes-A systematic review

INTRODUCTION

Dietary polyunsaturated fatty acids (PUFAs) have immunoregulatory properties. Breast milk is rich in PUFA, and it has been hypothesized that these PUFAs may be important in the aetiology of allergic diseases. Despite a growing body of evidence, the associations between breast milk PUFA and allergic disease have not previously been systematically reviewed.

METHODS

The search was performed in PubMed and EMBASE databases using breastfeeding, fatty acid and allergic disease terms. Two authors were involved in selecting papers for review according to the inclusion criteria and extracting information on study characteristics and measures of association. Only studies that reported numeric associations between concentration of breast milk fatty acids and allergic disease outcomes were included.

RESULTS

A total of 18 papers met the inclusion criteria, reporting results from 15 study populations. The majority were cohort studies (n=11), with data from only two case-control and two cross-sectional studies. Sample size varied between 30 and 352 participants, and follow-up time of the cohorts varied between 3 months and 14 years. Nine studies reported on eczema, seven reported on sensitization, and only five reported on asthma/wheeze. There was heterogeneity among studies in terms of presenting the association between PUFA and allergy; therefore, estimates could not be pooled. Only a few studies observed associations between n-3 and n-6 PUFAs and allergic disease, and the magnitude of this effect varied greatly.

CONCLUSIONS

There is insufficient evidence to suggest that colostrum or breast milk polyunsaturated fatty acids influence the risk of childhood allergic diseases.

Human Milk and Allergic Diseases: An Unsolved Puzzle

There is conflicting evidence on the protective role of breastfeeding in relation to the development of allergic sensitisation and allergic disease. Studies vary in methodology and definition of outcomes, which lead to considerable heterogeneity. Human milk composition varies both within and between individuals, which may partially explain conflicting data. It is known that human milk composition is very complex and contains variable levels of immune active molecules, oligosaccharides, metabolites, vitamins and other nutrients and microbial content. Existing evidence suggests that modulation of human breast milk composition has potential for preventing allergic diseases in early life. In this review, we discuss associations between breastfeeding/human milk composition and allergy development.

Breast milk polyunsaturated fatty acids: associations with adolescent allergic disease and lung function

BACKGROUND

It has been hypothesized that n-3 PUFA in breast milk may assist immune and lung development. There are very limited data on possible long-term effects on allergic disease and lung function. The aim was to investigate associations of n-3 and n-6 PUFA levels in colostrum and breast milk with allergic disease and lung function at ages 12 and 18 years.

METHODS

Polyunsaturated fatty acids were measured in 194 colostrum samples and in 118 three-month expressed breast milk samples from mothers of children enrolled in the Melbourne Atopy Cohort (MACS) Study, a high-risk birth cohort study. Associations with allergic diseases, skin prick tests and lung function assessed at 12 and 18 years were estimated using multivariable regression.

RESULTS

Higher levels of n-3 but not n-6 PUFAs in colostrum were associated with a trend towards increased odds of allergic diseases, with strong associations observed for allergic rhinitis at 12 (OR = 5.69[95% CI: 1.83,17.60] per weight%) and 18 years (4.43[1.46,13.39]) and eczema at 18 years (9.89[1.44, 68.49]). Higher levels of colostrum n-3 PUFAs were associated with reduced sensitization (3.37[1.18, 9.6]), mean FEV₁ (-166 ml [-332, -1]) and FEV₁ /FVC ratio (-4.6%, [-8.1, -1.1]) at 12 years.

CONCLUSION

Higher levels of colostrum n-3 PUFAs were associated with increased risks of allergic rhinitis and eczema up to 18 years, and sensitization and reduced lung function at 12 years. As residual confounding may have caused these associations, they should be replicated, but these results could indicate that strategies that increase maternal n-3 PUFA intake may not aid in allergic disease prevention.

Evidence for the essentiality of arachidonic and docosahexaenoic acid in the postnatal maternal and infant diet for the development of the infant’s immune system early in life

Long-chain polyunsaturated fatty acids (LCPUFA), especially the balance between arachidonic (AA) and docosahexaenoic (DHA) acids are known to have important immunomodulatory roles during the postnatal period when the immune system is rapidly developing. AA and DHA are required in infant formula in many countries but are optional in North America. The rationale for adding these LCPUFA to full-term formula is based on their presence in breast milk and randomized controlled studies that suggest improved cognitive function in preterm infants, but results are more variable in full-term infants. Recently, the European Food Safety Authority has proposed, based on a lack of functional evidence, that AA is not required in infant formula for full-term infants during the first year of life but DHA should remain mandatory. The purpose of this review is to review the evidence from epidemiological and intervention studies regarding the essentiality of AA and DHA in the postnatal infant and maternal diet (breast-feeding) for the immune system development early in life. Although studies support the essentiality of DHA for the immune system development, more research is needed to rule out the essentiality of AA. Nevertheless, intervention studies have demonstrated improvement in many markers of immune function in infants fed formula supplemented with AA and DHA compared with unsupplemented formula, which appears to consistently result in beneficial health outcomes including reduction in the risk of developing allergic and atopic disease early in life.

Dietary n-3 long chain polyunsaturated fatty acids in allergy prevention and asthma treatment

The rise in non-communicable diseases, such as allergies, in westernized countries links to changes in lifestyle and diet. N-3 long chain polyunsaturated fatty acids (LCPUFA) present in marine oils facilitate a favorable milieu for immune maturation and may contribute to allergy prevention. N-3 LCPUFA can suppress innate and adaptive immune activation and induce epigenetic changes. Murine studies convincingly show protective effects of fish oil, a source of n-3 LCPUFA, in food allergy and asthma models. Observational studies in human indicate that high dietary intake of n-3 LCPUFA and low intake of n-6 PUFA may protect against the development of allergic disease early in life. High n-6 PUFA intake is also associated with an increased asthma risk while n-3 LCPUFA may be protective and reduce symptoms. The quality of the marine oil used has impact on efficacy of allergy prevention and several observations link in particular n-3 LCPUFA DHA to allergy suppression. Randomized controlled trials indicate that optimal timing, duration and dosage of n-3 LC-PUFA is required to exert an allergy protective effect. Supplementation during early pregnancy and lactation has shown promising results regarding allergy prevention. However these findings should be confirmed in a larger cohort. Although clinical trials in asthma patients reveal no consistent clinical benefits of n-3 LCPUFA supplementation on lung function, it can suppress airway inflammation. Future food-pharma approaches may reveal whether adjunct therapy with dietary n-3 LCPUFA can improve allergy prevention or immunotherapy via support of allergen specific oral tolerance induction or contribute to the efficacy of drug therapy for asthma patients.

Allergic diseases among children: nutritional prevention and intervention

Allergic diseases comprise a genetically heterogeneous group of chronic, immunomediated diseases. It has been clearly reported that the prevalence of these diseases has been on the rise for the last few decades, but at different rates, in various areas of the world. This paper discusses the epidemiology of allergic diseases among children and their negative impact on affected patients, their families, and societies. These effects include the adverse effects on quality of life and economic costs. Medical interest has shifted from tertiary or secondary prevention to primary prevention of these chronic diseases among high-risk infants in early life. Being simple, practical, and cost-effective are mandatory features for any candidate methods delivering these strategies. Dietary therapy fits this model well, as it is simple, practical, and cost-effective, and involves diverse methods. The highest priority strategy is feeding these infants breast milk. For those who are not breast-fed, there should be a strategy to maintain beneficial gut flora that positively influences intestinal immunity. We review the current use of probiotics, prebiotics, and synbiotics, and safety and adverse effects. Other dietary modalities of possible potential in achieving this primary prevention, such as a Mediterranean diet, use of milk formula with modified (hydrolyzed) proteins, and the role of micronutrients, are also explored. Breast-feeding is effective in reducing the risk of asthma, allergic rhinitis, and atopic eczema among children. In addition, breast milk constitutes a major source of support for gut microbe colonization, due to its bifidobacteria and galactooligosaccharide content. The literature lacks consensus in recommending the addition of probiotics to foods for prevention and treatment of allergic diseases, while prebiotics may prove to be effective in reducing atopy in healthy children. There is insufficient evidence to support soy formulas or amino acid formulas for prevention of allergic disease. A healthy diet, such as the Mediterranean diet, may have a protective effect on the development of asthma and atopy in children. In children with asthma and allergic diseases, vitamin D deficiency correlates strongly with asthma, allergic rhinitis, and wheezing.

Breast milk fatty acid composition has a long-term effect on the risk of asthma, eczema, and sensitization

BACKGROUND

Levels of n-3 polyunsaturated fatty acids (PUFAs) and n-6 PUFAs in breast milk are associated with the development of allergic diseases up to school age. However, it is unknown whether this relationship persists when the child becomes older. We therefore studied the association between levels of n-3 PUFAs and n-6 PUFAs in breast milk of allergic- and nonallergic mothers and asthma, eczema and sensitization up to the age of 14 years.

METHODS

The study was nested in the ongoing PIAMA birth cohort. At the child's age of 3 months, 276 mothers provided a breast milk sample. Asthma (N total = 269) and eczema (N total = 274) were self-reported up to the child's age of 14 years. Specific serum IgE levels were measured at the ages of 4, 8 and 12 years (N total = 216). Generalized estimating equations analyses were used to take account of repeated observations.

RESULTS

Asthma up to the age of 14 years is less prevalent in children of allergic mothers receiving breast milk with higher levels of n-3 long chain polyunsaturated (LCP) fatty acids (OR 0.50; 95% CI 0.31-0.79), and more prevalent in children of nonallergic mothers receiving breast milk with higher levels of n-6LCP (OR 1.86; 95% CI 1.14-3.03). Weaker associations in similar direction were observed for eczema and sensitization. Direction of associations were consistent and of similar magnitude throughout childhood.

CONCLUSION

The association between breast milk fatty acid composition and asthma, eczema and sensitization persists up to the age of 14 years in children of both allergic and nonallergic mothers.

The role of the early-life environment in the development of allergic disease

A consensus has been reached that the development of allergic disorders is strongly influenced by early life exposures. An overview of several prenatal and early life factors that have been investigated for their associations with development of childhood allergy is presented. Delivery mode, the gut microbiome, vitamin D, folate, breastfeeding, pets, antibiotics, environmental tobacco smoke, and airborne traffic pollutants are discussed. Although many studies suggest an effect, overall, no risk factors clearly increase or reduce the risk of allergic outcomes.

Exclusive breastfeeding is associated with reduced cow's milk sensitization in early childhood

BACKGROUND

Although breastfed infants have consistently been reported as having fewer infections and respiratory morbidity during infancy, none have reached a definitive conclusion as to whether breastfeeding is an effective strategy to prevent allergic diseases. This study aims to investigate the relationship between exclusive breastfeeding and sequential changes of several biomarkers of allergy, such as absolute eosinophil count, total IgE level, and specific IgE level during the first 3 yrs of life.

METHODS

This is an unselected, population-based study that is part of a prospective birth cohort called the PATCH (Prediction of Allergy in Taiwanese Children). Blood analysis was performed at ages 6, 12, 18, 24, and 36 months. Clinical records of breastfeeding and detailed questionnaires regarding to allergic diseases were also obtained.

RESULTS

Analysis comparing exclusive breastfeeding ≥4 months with those <4 months and those partially breastfed showed a decreased risk of sensitization toward cow's milk protein up to the age of 2 yr (adjusted OR for cow's milk sensitization at 12 months was 0.2 [95% CI, 0.07-0.5]), at 18 months of age it was 0.2 [95% CI, 0.07-0.5], and at 24 months of age it was 0.2 [95% CI, 0.04-0.7]). In addition, although not significant, children of the exclusive breastfeeding group showed a trend of lower absolute eosinophil counts than their counterparts at all ages, and a lower total IgE level at the age of 3 yr.

CONCLUSIONS

Results of this study suggest that exclusive breastfeeding is associated with a reduced risk of cow's milk protein sensitization during early childhood.

Prevention of asthma: where are we in the 21st century?

Asthma is the most common chronic disease of childhood and, in the latter part of the 20th century, reached epidemic proportions. Asthma is generally believed to result from gene-environment interactions. There is consensus that a 'window of opportunity' exists during pregnancy and early in life when environmental factors may influence its development. We review multiple environmental, biologic and sociologic factors that may be important in the development of asthma. Meta-analyses of studies have demonstrated that multifaceted interventions are required in order to develop asthma prevention. Multifaceted allergen reduction studies have shown clinical benefits. Asthma represents a dysfunctional interaction with our genes and the environment to which they are exposed, especially in fetal and early infant life. The increasing prevalence of asthma also may be an indication of increased population risk for the development of other chronic non-communicable autoimmune diseases. This review will focus on the factors which may be important in the primary prevention of asthma. Better understanding of the complex gene-environment interactions involved in the development of asthma will provide insight into personalized interventions for asthma prevention.

Fatty-acid composition of maternal and umbilical cord plasma and early childhood atopic eczema in a Spanish cohort

BACKGROUND/OBJECTIVES

Fatty-acid status during in-utero development might influence the risk of atopic diseases in early childhood. The aim of this work was to identify the relationship between maternal plasma and cord blood fatty acid (FA) composition and the risk of atopic eczema in the offspring at 14 months of age.

SUBJECTS/METHODS

Two hundred and eleven non-atopic mothers and their children were studied. Mothers were recruited in their first trimester of gestation and children were monitored until 14 months of age. Samples of maternal plasma and cord blood plasma were analyzed to determine the FA profile of total lipids. Presence of atopic eczema in the infants was documented through questionnaires at 6 and 14 months of age.

RESULTS

Higher concentrations of total long-chain polyunsaturated FA (LC-PUFA) were found in maternal plasma of non-atopic children in relation to atopic group. Moreover, this maternal plasma LC-PUFA content was negatively correlated with the atopic eczema (odds ratios (OR)=0.83, P=0.04) in infants. Regarding cord blood samples, docosahexaenoic acid (DHA C22:6n3) and the sum of total n-3 and of LC-PUFA n-3 showed a negative correlation with the prevalence of the disease (OR=0.50, 0.49 and 0.49, respectively).

CONCLUSIONS

Our results show that the fatty-acid status of the fetus during pregnancy has an important role in the development of atopic eczema in early childhood. The prevalence of this atopic disorder is related to lower cord blood plasma levels of FA belonging to n-3 series, especially DHA.

Fatty acids in breast milk associated with asthma-like symptoms and atopy in infancy: a longitudinal study

OBJECTIVE

The relationship between fatty acids (FAs) in breast milk and the risk of childhood allergies is controversial. We prospectively investigated the relationship between FAs in colostrum and breast milk and asthma-like symptoms (AS) and atopy in infancy.

METHODS

Pregnant women were recruited in Columbia and Charleston, South Carolina. Colostrum and mature milk samples were collected. The concentrations of n-3 FAs (eicosapentaenoic acid, α-linolenic acid, docosapentaenoic acid, and docosahexaenoic acid) and n-6 FAs (linoleic acid, arachidonic acid, and eicosadienoic acid) were determined by gas chromatography. AS were ascertained at 6 and 12 months of age and atopy (skin prick test) at 12 months. FAs were dichotomized (high vs. median and low). Generalized estimating equations were used to determine the effect of FAs on repeated AS, compensating for intra-individual correlations and adjusting for confounders. Log-linear regression was used to analyze atopy.

RESULTS

FAs were analyzed in 24 colostrum and 78 breast milk samples. High levels of total n-6 (lipid based) FAs in breast milk were associated with an increased risk of AS in infants (risk ratio (RR) = 2.91; 95% confidence interval (CI): 1.37, 6.18), even after controlling for total n-3 FAs (RR = 2.07, 95% CI: 1.12, 3.85). High levels of total n-3 FAs controlling for n-6 FAs decreased the risk of atopy at the age of 12 months.

CONCLUSIONS

High levels of total n-6 polyunsaturated fatty acids (PUFAs) in breast milk are associated with an increased risk for AS, whereas high levels of total n-3 PUFAs decreased the risk of atopy. These data suggest that the effects of n-3 and n-6 PUFAs on allergic disorders should be further explored.

How changes in nutrition have influenced the development of allergic diseases in childhood

The increasing prevalence of allergic diseases in childhood in the last decades could be linked to concomitant dietary changes, especially with the modified and lower consumption of fruit, vegetables and minerals. The consumption of these foods by pregnant women and children in the first years of life seems to be associated with a reduced risk of asthma and related symptoms. Foods that can prevent the development of wheezing through their antioxidant effects contain vitamin C and selenium; blood levels of these elements correlate negatively with the risk of wheezing. Intake of vitamin E during pregnancy also appears to be correlated with a reduced risk of wheezing for the unborn child. Similarly, low intake of zinc and carotenoids by pregnant women is associated with an increased risk of wheezing and asthma in childhood. Fiber also has anti-inflammatory properties and protective effects against allergic diseases such as atopic dermatitis and asthma. The consumption of fat influences the development of the airways. Populations in Western countries have increased their consumption of n-6 PUFAs and, in parallel, reduced n-3 PUFAs. This has led to decreased production of PGE2, which is believed to have a protective effect against inflammation of the airways. Conflicting hypotheses also concern vitamin D; both an excess and a deficiency of vitamin D, in fact, have been associated with an increased risk of asthma. Further studies on the role of these substances are necessary before any conclusions can be drawn on a clinical level.

Fatty acids as biocompounds: their role in human metabolism, health and disease: a review. part 2: fatty acid physiological roles and applications in human health and disease

BACKGROUND

This is the second of two review parts aiming at describing the major physiological roles of fatty acids, as well as their applications in specific conditions related to human health.

RESULTS

The review included the current literature published in Pubmed up to March 2011. In humans, fatty acids are a principle energy substrate and structural components of cell membranes (phospholipids) and second messengers. Fatty acids are also ligands of nuclear receptors affecting gene expression. Longer-chain (LC) polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid are precursors of lipid mediators such as eicosanoids (prostaglandins, leukotrienes, thromboxanes), resolvins and neuroprotectins. Lipid mediators produced by EPA and DHA (LC n-3 PUFA; mainly found in oily fish) are considered as inflammation-resolving, and thus, fish oil has been characterised as antiinflammatory. Recommendations for EPA plus DHA intake from oily fish vary between 250-450 mg/day. Dietary reference values for fat vary between nutrition bodies, but mainly agree on a low total and saturated fat intake. The existing literature supports the protective effects of LC n-3 PUFA (as opposed to n-6 PUFA and saturated fat) in maternal and offspring health, cardiovascular health, insulin sensitivity, the metabolic syndrome, cancer, critically ill patients, and immune system disorders.

CONCLUSION

Fatty acids are involved in multiple pathways and play a major role in health. Further investigation and a nutrigenomics approach to the effects of these biocompounds on health and disease development are imperative and highlight the importance of environmental modifications on disease outcome.

Maternal signals for progeny prevention against allergy and asthma

Allergy and asthma are chronic inflammatory diseases which result from complex gene-environment interactions. Recent evidence indicates the importance of prenatal and postnatal developmental processes in terms of maturation of balanced immune responses. According to the current view, gene-environment interactions during a restricted time frame are responsible for programming of the immune system in favor of allergic immune mechanisms later in life. The interaction between genes and environment is complex and only partially understood; however, heritable epigenetic modifications including chemical additions in and alternative packaging of the DNA have been shown to play a crucial role in this context. Novel data indicate that epigenetic mechanisms contribute to the development of T-helper cell function. Environmental factors, including diesel exhaust particles (DEP), vitamins and tobacco smoke, operate through such mechanisms. Furthermore, the role of environmental microbes provides another and maybe even more important group of exogenous exposures which operates in this critical time frame.

Low breast milk levels of long-chain n-3 fatty acids in allergic women, despite frequent fish intake

BACKGROUND

Long-chain n-3 polyunsaturated fatty acids (PUFAs) have immune regulating and anti-inflammatory effects. However, their role in allergic disease is unclear. Allergic diseases are immunologically heterogeneous, and we hypothesized that n-3 fatty acid composition in serum and breast milk may vary according to clinical manifestations. Further, animal studies have shown reduction of serum-PUFA levels during allergic inflammation.

OBJECTIVE

To investigate fatty acid composition in breast milk and serum from women with different atopic disease manifestations. Secondly, to determine whether low PUFA levels reflected insufficient intakes.

METHODS

Fatty acids were analysed in breast milk and serum of women with atopic eczema and respiratory allergy (n=16), only respiratory allergy (n=7), as well as healthy women (n=22). Dietary intake of foods expected to affect long-chain n-3 PUFA levels were estimated by food-frequency questionnaire. The fatty acid pattern was related to diagnostic group and intake of relevant food items using a multivariate pattern recognition method (partial least squares projections to latent structures and discriminant analysis). Results Women with a combination of eczema and respiratory allergy had lower breast milk levels of several PUFAs (arachidonic acid, eicosapentaenoic acid, EPA, docosahexaenoic acid, DHA, and docosapentaenoic acid, DPA), and a lower ratio of long-chain n-3 PUFAs/n-6 PUFAs. Their PUFA levels differed not only from that of healthy women, but also from that of women with only respiratory allergy. The latter had a fatty acid pattern similar to that of healthy women. Despite low EPA, DHA and DPA levels women with eczema and respiratory allergy consumed no less fish than did healthy women.

CONCLUSION & CLINICAL RELEVANCE

Our data suggest that reduced levels of long-chain n-3 fatty acids in serum and breast milk characterize women with extensive allergic disease including eczema, and are not related to low fish intake. Consumption of PUFAs during the allergic process may explain these findings.

Genetic variants in the FADS gene cluster are associated with arachidonic acid concentrations of human breast milk at 1.5 and 6 mo postpartum and influence the course of milk dodecanoic, tetracosenoic, and trans-9-octadecenoic acid concentrations over the duration of lactation

BACKGROUND

Breastfeeding is considered an optimal nutritional source of n-6 (omega-6) and n-3 (omega-3) fatty acids (FAs) for the proper visual and cognitive development of newborn children. In addition to maternal nutrition as an important regulator of FA concentrations, first results exist on an association of breast-milk FAs with single nucleotide polymorphisms (SNPs) in the FADS gene cluster, which encodes the rate-limiting enzymes in the elongation-desaturation pathway of long-chain polyunsaturated fatty acids (LC-PUFAs).

OBJECTIVE

We analyzed the influence of FADS SNPs on breast-milk FA concentrations and their time course during lactation in the Ulm Birth Cohort study, which comprised 772 nursing mothers at 1.5 mo after giving birth, and in a subset of 463 mothers who were still breastfeeding at 6 mo postpartum.

DESIGN

We conducted linear regression analysis of 8 FADS SNPs with FA concentrations at both time points separately and assessed the genotype effect over time in a longitudinal analysis by using a generalized estimating equation regression model.

RESULTS

We observed significant associations of FADS genotypes with arachidonic acid (AA) concentrations and the 20:4n-6/20:3n-6 ratio at both time points but no association of FADS SNPs with the time course of AA concentrations. A longitudinal analysis of FAs other than LC-PUFAs by genotype over time showed associations for dodecanoic acid, cis-15-tetracosenoic acid, and trans-9-octadecenoic acid.

CONCLUSIONS

Maternal FADS genotypes are associated with breast-milk AA concentrations and might therefore influence the supply of this FA for children. Furthermore, our data indicate an interrelation between the LC-PUFA pathway and saturated and monounsaturated FAs.

Maternal fatty acid status in pregnancy and childhood atopic manifestations: KOALA Birth Cohort Study

BACKGROUND

Prevalence of atopic disorders has increased rapidly, but aetiological factors responsible for this increase are still largely unknown. Prenatal exposure to a pro-inflammatory fatty acid status is hypothesized although little research has been carried out.

OBJECTIVE

To investigate whether prenatal fatty acid exposures are associated with atopy in childhood.

METHODS

In the KOALA Birth Cohort Study, maternal blood samples (n=1275) at 34-36 weeks of pregnancy were assayed for n-6 and n-3 long-chain polyunsaturated fatty acids (LCPs). The full spectrum of offspring atopic manifestations (wheeze, asthma, allergic rhinoconjunctivitis, eczema, atopic dermatitis, allergic sensitization, and high total IgE) until the age of 6-7 years was assessed by repeated parental questionnaires and measurements of total and specific IgE. Associations of maternal fatty acid status with child atopic outcomes were analysed using multivariable logistic regression and generalized estimating equations for repeated measurements.

RESULTS

High ratio of maternal n-6 vs. n-3 LCPs was associated with a lower risk of eczema in the child (P for trend 0.012). More specifically, we found a decreased risk of eczema in the first 7 months of life with increasing arachidonic acid levels (P for trend 0.013). No associations were found between maternal fatty acids and offspring airway-related atopic manifestations, sensitization, or high total IgE.

CONCLUSION AND CLINICAL RELEVANCE

The development of atopic disorders in early childhood is associated with prenatal exposure to n-6 vs. n-3 fatty acids, but with inconsistencies between different manifestations. Further exploration of associations with maternal diet and genetic variants in genes regulating fatty acid metabolism are required. This study shows that the influence of prenatal exposure to fatty acids on the risk of eczema in the child is limited to the first year of life.

Fetal epigenetic mechanisms and innate immunity in asthma

Allergy and asthma are chronic inflammatory diseases that result from complex gene-environment interactions. Recent evidence points to the importance of prenatal and postnatal developmental processes in the maturation of balanced immune responses. Novel data indicate that epigenetic mechanisms contribute to the development of T-helper-cell function. Environmental factors, including diesel exhaust particles, vitamins, and tobacco smoke, operate through such mechanisms. Furthermore, the role of environmental microbes provides another-and maybe an even more important-group of exogenous exposures that operate in this critical time frame. A better understanding of fetal immuno-maturation conditions will provide the basis for the development of novel allergo-protective clinical strategies.

Fatty acids in breast milk and development of atopic eczema and allergic sensitisation in infancy

BACKGROUND

One of the explanations for the increasing prevalence of atopic diseases is a relative low perinatal supply of n-3 fatty acids. However, this does not explain the protective effects of whole-fat dairy products or high levels of transfatty acids in breast milk, observed in some studies. We evaluated the role of perinatal supply of fatty acids in the early development of atopic eczema and allergic sensitisation.

METHODS

Fatty acids, including n-3 long-chain polyunsaturated fatty acids (LCPs) as well as ruminant fatty acids (rumenic acid, cis-9,trans-11-C18:2 conjugated linoleic acid; and vaccenic acid, trans-11-C18:1), were determined in breast milk sampled at 1 month postpartum from 310 mother-infant pairs in the KOALA Birth Cohort Study, the Netherlands. Children were followed for atopic outcomes until 2 years of age.

RESULTS

Higher concentrations of n-3 LCPs as well as ruminant fatty acids were associated with lower risk of (1) parent-reported eczema, (2) atopic dermatitis (UK Working Party criteria), and (3) sensitisation at age 1 year (as revealed by specific serum IgE levels to cow's milk, hen's egg and/or peanut). In multivariable logistic regression analysis, the inverse associations between ruminant fatty acid concentrations in breast milk and atopic outcomes were found to be independent from n-3 LCPs.

CONCLUSIONS

The results confirm a protective role of preformed n-3 LCPs in the development of atopic disease. Moreover, this is the first study in humans confirming results from animal studies of protective effects of ruminant fatty acids against the development of atopic manifestations.

Food allergy: separating the science from the mythology

Numerous genes are involved in innate and adaptive immunity and these have been modified over millions of years. During this evolution, the mucosal immune system has developed two anti-inflammatory strategies: immune exclusion by the use of secretory antibodies to control epithelial colonization of microorganisms and to inhibit the penetration of potentially harmful agents; and immunosuppression to counteract local and peripheral hypersensitivity against innocuous antigens, such as food proteins. The latter strategy is called oral tolerance when induced via the gut. Homeostatic mechanisms also dampen immune responses to commensal bacteria. The mucosal epithelial barrier and immunoregulatory network are poorly developed in newborns. The perinatal period is, therefore, critical with regard to the induction of food allergy. The development of immune homeostasis depends on windows of opportunity during which innate and adaptive immunity are coordinated by antigen-presenting cells. The function of these cells is not only orchestrated by microbial products but also by dietary constituents, including vitamin A and lipids, such as polyunsaturated omega-3 fatty acids. These factors may in various ways exert beneficial effects on the immunophenotype of the infant. The same is true for breast milk, which provides immune-inducing factors and secretory immunoglobulin A, which reinforces the gut epithelial barrier. It is not easy to dissect the immunoregulatory network and identify variables that lead to food allergy. This Review discusses efforts to this end and outlines the scientific basis for future food allergy prevention.

Increased risk of eczema but reduced risk of early wheezy disorder from exclusive breast-feeding in high-risk infants

BACKGROUND

Breast-feeding is recommended for the prevention of eczema, asthma, and allergy, particularly in high-risk families, but recent studies have raised concern that this may not protect children and may even increase the risk. However, disease risk, disease manifestation, lifestyle, and the choice to breast-feed are interrelated, and therefore, analyzing true causal effects presents a number of methodologic challenges.

OBJECTIVE

First, to assess the effect from duration of exclusive breast-feeding on the development of eczema and wheezy disorders during the first 2 years of life in a high-risk clinical birth cohort. Second, to assess any influence from the fatty acid composition of mother's milk on the risk from breast-feeding.

METHODS

We studied disease development during the first two years of life of the 411 infants from the Copenhagen Study on Asthma in Childhood (COPSAC) birth cohort, born to mothers with a history of asthma. We analyzed the effect from duration of breast-feeding before disease onset on the disease risk, avoiding the effect from disease-related modification of exposure (inverse causation). Polyunsaturated fatty acids were measured in breast milk.

RESULTS

Breast-feeding significantly increased the risk of eczema adjusted for demographics, filaggrin variants, parents' eczema, and pets at home (N = 306; relative risk, 2.09; 95% CI 1.15-3.80; P = .016) but reduced the risk of wheezy episodes (relative risk, 0.67; 95% CI 0.48-0.96; P = .021) and of severe wheezy exacerbation (relative risk, 0.16; 95% CI 0.03-1.01; P = .051). There was no association between the fatty acid composition of mother's milk and the risk of eczema or wheeze.

CONCLUSION

The risk of eczema was increased in infants with increasing duration of breast-feeding. In contrast, the risk of wheezy disorder and severe wheezy exacerbations was reduced. There were no significant effects from the fatty acid composition of the breast milk on risk of eczema or wheezy disorders.

Montelukast: Pharmacology, Safety, Tolerability and Efficacy

Allergic rhinitis and asthma are common disorders effecting large percentages of the population of Western countries. There are multiple treatment options available for allergic rhinitis and asthma and stepwise approaches to therapy have been recommended. Montelukast is a cysteinyl leukotriene receptor antagonist that has been found to be effective both in the treatment of allergic rhinitis and asthma. This paper will describe the pharmacology, safety, efficacy and tolerability of montelukast. It will examine the comparative efficacy of montelukast to other medications for the treatment of allergic rhinitis and asthma, as well as discuss the recent studies of combination therapy.

Docosahexaenoic acid and lactation

Docosahexaenoic acid (DHA) is an important component of membrane phospholipids in the retina and brain and accumulates rapidly in these tissues during early infancy. DHA is present in human milk, but the amount varies considerably and is largely dependent on maternal diet. This article reviews data addressing the impact of different DHA intakes by lactating women on infant and maternal outcomes to determine if available data are sufficient to estimate optimal breast milk DHA content and estimate dietary reference intakes (DRIs) for DHA by breast-feeding mothers. Results of published observational studies and interventional trials assessing the impact of maternal DHA intake (or breast milk DHA content) on infant visual function, neurodevelopment, and immunologic status were reviewed. Studies related to the potential impact of DHA intake on depression or cognitive function of lactating women also were reviewed. Although only a limited number of studies are available in the current medical literature, and study results have not been consistent, better infant neurodevelopment and/or visual function have been reported with higher vs. lower levels of breast milk DHA. The effect of DHA intake on the incidence or severity of depression in lactating women is not clear. Increasing breast milk DHA content above that typically found in the US, by increasing maternal DHA intake, may confer neurodevelopmental benefits to the recipient breast-fed infant. However, current data are insufficient to permit determination of specific DRIs during this period.

Relation of DNA methylation of 5'-CpG island of ACSL3 to transplacental exposure to airborne polycyclic aromatic hydrocarbons and childhood asthma

In a longitudinal cohort of approximately 700 children in New York City, the prevalence of asthma (>25%) is among the highest in the US. This high risk may in part be caused by transplacental exposure to traffic-related polycyclic aromatic hydrocarbons (PAHs) but biomarkers informative of PAH-asthma relationships is lacking. We here hypothesized that epigenetic marks associated with transplacental PAH exposure and/or childhood asthma risk could be identified in fetal tissues. Mothers completed personal prenatal air monitoring for PAH exposure determination. Methylation sensitive restriction fingerprinting was used to analyze umbilical cord white blood cell (UCWBC) DNA of 20 cohort children. Over 30 DNA sequences were identified whose methylation status was dependent on the level of maternal PAH exposure. Six sequences were found to be homologous to known genes having one or more 5'-CpG island(s) (5'-CGI). Of these, acyl-CoA synthetase long-chain family member 3 (ACSL3) exhibited the highest concordance between the extent of methylation of its 5'-CGI in UCWBCs and the level of gene expression in matched fetal placental tissues in the initial 20 cohort children. ACSL3 was therefore chosen for further investigation in a larger sample of 56 cohort children. Methylation of the ACSL3 5'-CGI was found to be significantly associated with maternal airborne PAH exposure exceeding 2.41 ng/m(3) (OR = 13.8; p<0.001; sensitivity = 75%; specificity = 82%) and with a parental report of asthma symptoms in children prior to age 5 (OR = 3.9; p<0.05). Thus, if validated, methylated ACSL3 5'CGI in UCWBC DNA may be a surrogate endpoint for transplacental PAH exposure and/or a potential biomarker for environmentally-related asthma. This exploratory report provides a new blueprint for the discovery of epigenetic biomarkers relevant to other exposure assessments and/or investigations of exposure-disease relationships in birth cohorts. The results support the emerging theory of early origins of later life disease development.

Transforming growth factor-beta is elevated in unpasteurized cow's milk

Unpasteurized milk consumption was associated with less atopy prevalence. Not only microbial load but also fatty acids and cytokines such as transforming growth factor-beta(1) (TGF-beta(1)) may play a role on the effect of unpasteurized milk. Levels of TGF-beta(1) in different cow's milk samples were evaluated: we consider raw unpasteurized milk before and after boiling, commercial pasteurized and micro-filtrated cow's milk and different commercially available cow's milk formulas. TGF-beta(1) concentration in raw unpasteurized cow's milk was 642.0 +/- 52.9 pg/ml before boiling and decreased significantly after boiling (302.7 +/- 50.59 pg/ml) (p < 0.05). TGF-beta(1) concentrations were also significantly lower in commercial pasteurized milk (246.2 +/- 43.15 pg/ml) and in commercial micro-filtrated milk (213.0 +/- 31.6 pg/ml) in comparison to unpasteurized unboiled milk (p = 0.002). The levels of TGF-beta(1) in all formula samples were below the threshold of detectability for the assays. As TGF-beta(1) in the milk may contribute to the development of the immature gastrointestinal tract by influencing IgA production and oral tolerance induction, we suggest to consider not only the microbial compounds but also the cytokine patterns to explain the protective effect of unpasteurized cow's milk on allergic disorders.

Prenatal arachidonic acid exposure and selected immune-related variables in childhood

Arachidonic acid (AA) is considered essential in fetal development and some of its metabolites are thought to be important mediators of the immune responses. Therefore, we studied whether prenatal exposure to AA is associated with some immune-related clinical conditions and plasma markers in childhood. In 280 children aged 7 years, atopy, lung function and plasma inflammation markers were measured and their relationships with early AA exposure were studied by linear and logistic regression analyses. AA exposure was deduced from AA concentrations in plasma phospholipids of the mothers collected at several time points during pregnancy and at delivery, and in umbilical cord plasma and arterial and venous wall phospholipids. In unadjusted regression analyses, significant positive associations were observed between maternal AA concentrations at 16 and 32 weeks of pregnancy (proxies for fetal AA exposure) and peak expiratory flow decline after maximal physical exercise and plasma fibrinogen concentrations of their children, respectively. However, after correction for relevant covariables, only trends remained. A significant negative relationship was observed between AA concentrations in cord plasma (reflecting prenatal AA exposure) and the average daily amplitude of peak expiratory flow at rest, which lost significance after appropriate adjustment. Because of these few, weak and inconsistent relationships, a major impact of early-life exposure to AA on atopy, lung function and selected plasma inflammation markers of children at 7 years of age seems unlikely.

Breastfeeding and allergies: time for a change in paradigm?

PURPOSE OF REVIEW

This review examines recent studies of the relationships between breastfeeding and the epidemiology of allergic diseases, especially atopic dermatitis in infants and asthma in early and later childhood.

RECENT FINDINGS

Results from observational birth cohort studies, case-control studies, and one cluster randomized intervention trial have generally failed to demonstrate a protective effect of breastfeeding on outcomes of atopic dermatitis, allergic sensitization, wheezing, or asthma. Difficulties in interpretation relate to the absence of nonbreastfed control or reference groups in some studies, meaning outcomes can only be compared between different durations of breastfeeding. Studies with a nonbreastfed control group suggest there is an increased risk for atopy and asthma associated with breastfeeding and that prolonged breastfeeding may eventually reduce this increased risk. The family history, sex of the child, and the presence of other risk factors for allergy and asthma also influence the outcome.

SUMMARY

Although breastfeeding is strongly recommended for its multiple benefits on child health, most recent studies do not confirm the 'conventional wisdom' that breastfeeding is protective against allergy and asthma. Early reduction in childhood wheezing may reflect protection from viral infections, but allergies and asthma at later ages may be increased.

Primary care from infancy to adolescence

The use of complementary and alternative medical (CAM) therapies is increasing among well children and adolescents and in those children who have special health care needs. Integrative pediatrics, a holistic practice that includes an examined integration of CAM and conventional therapies, is ideally suited for primary care. This article describes how to integrate evidence-based CAM therapies for colic, atopy, ADHD, eating disorders, and other conditions commonly seen in primary care practice.

Consumption of organic foods and risk of atopic disease during the first 2 years of life in the Netherlands

We prospectively investigated whether organic food consumption by infants was associated with developing atopic manifestations in the first 2 years of life. The KOALA Birth Cohort Study in the Netherlands (n 2764) measured organic food consumption, eczema and wheeze in infants until age 2 years using repeated questionnaires. Diet was defined as conventional ( 90 % organic). Venous blood samples taken from 815 infants at 2 years of age were analysed for total and specific IgE. Multivariate logistic regression models were fitted to control for potential confounding factors. Eczema was present in 32 % of infants, recurrent wheeze in 11 % and prolonged wheezing in 5 %. At 2 years of age, 27 % of children were sensitised against at least one allergen. Of all the children, 10 % had consumed a moderately organic diet and 6 % a strictly organic diet. Consumption of organic dairy products was associated with lower eczema risk (OR 0.64 (95 % CI 0.44, 0.93)), but there was no association of organic meat, fruit, vegetables or eggs, or the proportion of organic products within the total diet with the development of eczema, wheeze or atopic sensitisation. Further studies to substantiate these results are warranted.

Is breast feeding a risk factor for eczema during the first year of life?

Breast feeding (BF) provides many advantages to the offspring; however, at present there is an ongoing debate as to whether or not it prevents allergic diseases. The aim of the current study was to investigate the effect of duration of BF on eczema in the first year of life. A birth cohort of 1128 infants was followed prospectively from 5 months of pregnancy. Data were collected using questionnaires, a medical examination and blood tests for allergy at the age of 1 yr. Breast feeding was not statistically significant associated with eczema in the first year of life [adj ORs with 95% CIs: 0.8 (0.4-1.3), 0.8 (0.5-1.3) and 1.0 (0.6-1.5) for BF duration of 1-6 wk, 7-12 wk and > or = 13 wk, respectively]. Eczema was positively associated with atopy and educational level of the mother, use of antibiotics in pregnancy and passive smoking by the child during the first 12 months. Regular postnatal contact of the infants with dogs was inversely associated with eczema. Breast feeding was positively associated with eczema among children with non-atopic parents [adj ORs with 95% CIs: 2.1 (0.4-10.6), 2.2 (0.4-11.3) and 1.9 (0.4-8.5) for BF duration of 1-6 wk, 7-12 wk and > or = 13 wk, respectively], whereas an inverse association was found among children with atopic parents [adj ORs with 95% CIs: 0.6 (0.3-1.3), 0.7 (0.3-1.4) and 0.9 (0.5-1.7) for the same BF durations]. However, these associations were not statistically significant. Breast feeding has no significant effect on the prevalence of eczema in the first year of life. The effect of BF on eczema in children depends on parental atopy.

Influence of organic diet on the amount of conjugated linoleic acids in breast milk of lactating women in the Netherlands

The aim of the present study was to find out whether the incorporation of organic dairy and meat products in the maternal diet affects the contents of the conjugated linoleic acid isomers (CLA) and trans-vaccenic acid (TVA) in human breast milk. To this purpose, milk samples from 312 breastfeeding mothers participating in the KOALA Birth Cohort Study have been analysed. The participants had documented varying lifestyles in relation to the use of conventional or organic products. Breast milk samples were collected 1 month postpartum and analysed for fatty acid composition. The content of rumenic acid (the main CLA) increased in a statistically significant way while going from a conventional diet (no organic dairy/meat products, 0.25 weight % (wt%), n 186) to a moderately organic diet (50-90 % organic dairy/meat, 0.29 wt%, n 33, P = 0.02) and to a strict organic diet (>90 % organic dairy/meat, 0.34 wt%, n 37, P </= 0.001). The levels of TVA were augmented among the participants with a moderately organic diet (0.54 wt%) and those with a strict organic diet (0.59 wt%, P </= 0.001), in comparison with the conventional group (0.48 wt%). After adjusting for covariables (recruitment group, maternal age, maternal education, use of supplements and season), statistical significance was retained in the group of the strict organic dairy users (P < 0.001 for rumenic acid). Hence, the levels of CLA and TVA in human milk can be modulated if breastfeeding mothers replace conventional dairy and/or meat products by organic ones. A potential contribution of CLA and TVA to health improvement is briefly discussed.