Breastfeeding, Childhood Asthma, and Allergic Disease

Abstract

The worldwide prevalence of childhood asthma has been increasing considerably, and the protection afforded by breastfeeding in its development has been the subject of controversy for more than 80 years. Previous systematic reviews have generally found a protective effect of breastfeeding on allergic outcomes, although many studies have methodological limitations. Although breastfeeding is protective against lower respiratory tract infection during infancy, such protection has not been demonstrated for asthma in all studies. Breastfeeding has health benefits for the mother and child. Exclusive breastfeeding for the first 6 months of an infant's life, with continued breastfeeding for up to 2 years or longer, is recognized as the “gold” standard for infant feeding because human milk is uniquely suited to the human infant, and its nutritional content and bioactivity promote a healthy development. There is increasing concern that the practice of delaying complementary foods until 6 months may exacerbate the risk of allergic disease. Breast milk contains immunological components that protect against infections and allergic disease in infancy. The composition of human breast milk is complex, containing factors that interact with the infant immune system and intestinal milieu including allergens, cytokines, immunoglobulins, polyunsaturated fatty acids, and chemokines. Transforming growth factor β is a cytokine in human milk involved in maintaining intestinal homeostasis, inflammation regulation, and oral tolerance development. Modern day society, with increased standards of hygiene, has changed the gut flora of Western infants, potentially impacting the risk of developing immune-mediated diseases including allergic disease and asthma. Microbial diversity is intrinsic to healthy immune maturation and function. Compared to breastfed infants, formula-fed infants had lower bacterial diversity and an altered intestinal microbiota in the first few weeks of life associated with an increased risk of eczema and asthma. Favorable gut colonization through continued breastfeeding may promote tolerance as well as protection when complementary feeding is initiated.

Prenatal and postnatal determinants in shaping offspring’s microbiome in the first 1000 days: study protocol and preliminary results at one month of life

“…Furthermore, the microbiome composition in early infancy is mostly dominated by species involved in human milk oligosaccharide (HMO) metabolism in breastfed infants [58]. These bioactive compounds seem to be beneficial to newborns as they not only promote healthier growth but also strengthen the immune system, they provide protection against allergies and may also offer protection from NCDs (such as type-2-diabetes, obesity), coeliac disease, diarrhea and many other metabolic disorders [59][60][61][62][63]. This is one of the main reasons why the World Health Organization (WHO) recommends that infants should be exclusively breastfed for the first 6 months of life [30].…”

Milk Other than Breast Milk and the Development of Asthma in Children 3 Years of Age. A Birth Cohort Study (2006-2011)

“…The World Health Organization (WHO) estimates 235 million people with the disease [2]. The worldwide prevalence of childhood asthma has been increasing considerably in the last few years [3]. The prevalence of asthma in Australian children is amongst the highest in the world [4].…”

“…The prevalence of asthma in Australian children is amongst the highest in the world [4]. Explanations for this increase are not yet clear thus limiting the opportunities to develop targeted primary prevention measures [3] Asthma is a variable phenotype and its definition across studies is highly inconsistent. Clinically, asthma is defined as a chronic inflammatory disorder of lungs that is characterized by recurrent episodes of wheezing, shortness of breath, tightness of chest and coughing, associated with limitation of airflow in the respiratory system [5].…”

“…Asthma has a broad spectrum of possible determinants extending from genetics to lifestyle to environmental factors [3]. Inherited factors hypothesized to be associated with the risk of asthma include: maternal asthma [6], young maternal age [7], low level of mother's education [8], Aboriginality [9] and child sex [10].…”

Effects of oocyte source, cell origin, and embryo reconstruction procedures on in vitro and in vivo embryo survival after goat cloning

“…This is especially true in less favorable regions such as the Semi-Arid area of Brazil, resulting in thousands of infant deaths worldwide each year (Boccolini et al, 2012). Several epidemiological studies have already demonstrated the benefits of breast feeding for the infant´s health, including passive immunedefense against infections by pathogenic microorganisms, growth stimuli to benign agents in the intestinal microbiota, development and maturation of the gastrointestinal tract, protection against asthma and allergies, and anti-inflammatory effects (Lönnerdal, 2003;Oddy, 2017). The positive effects of human milk to breastfed children are reflected in an improved general health, adequate growth and development including epigenetic beneficial changes, lower susceptibility to chronic and acute diseases during and after childhood, (American Academy of Pediatrics, 1997, Verduci et al, 2014, and lower incidence of infections of the gastrointestinal, respiratory and urinary tracts (Levy, 1998).…”