Allergies

The research below explores the effects of breastfeeding, formula feeding and the early introduction of certain foods on the prevalence of allergies in babies and young children.

Hydrolysed formula and allergy prevention

Over the past 30 years, hydrolysed formula has been recommended to prevent allergy in infants – an endorsement supported by historically fraudulent research and selectively reported trials. New TRIGR trial results are discussed in this editorial which reinforce the evidence that whilst extensively hydrolysed formula has a role in managing children with certain intestinal conditions or milk allergy, there is little evidence that hydrolysed formula aids in feeding healthy infants or helps to reduce allergy risk.

Genuneit, J., Boyle, R. Hydrolysed formula and allergy prevention. February 2021. Wiley. DOI: 10.1111/pai.13470

Assessment of Evidence About Common Infant Symptoms and Cow’s Milk Allergy

This study aims to understand whether cows’ milk allergy (CMA) guideline recommendations might promote CMA over-diagnosis or undermine breastfeeding, particularly in light of recent increases in sales of specialized formula for managing CMA. Authors reviewed recommendations made in CMA guidelines and critically appraised 2 key recommendations. In their key conclusions, the authors found that recommendations to manage common infant symptoms as CMA are not evidence-based, especially in breastfed infants who are not directly consuming cow’s milk. Such recommendations may cause harm by undermining confidence in breastfeeding.

Munblit D, Perkin MR, Palmer DJ, Allen KJ, Boyle RJ. Assessment of Evidence About Common Infant Symptoms and Cow’s Milk Allergy. JAMA Pediatr. 2020;174(6):599–608. doi:10.1001/jamapediatrics.2020.0153

Effect of an Intervention to Promote Breastfeeding on Asthma, Lung Function, and Atopic Eczema at Age 16 Years

In this adolescent follow-up of a cluster randomized trial in Belarus, which assessed the effect of a breastfeeding promotion intervention vs usual care among 13,557 participants, there was a 54% reduction in atopic eczema on skin examination but no significant effect on lung function (spirometry) and self-reported asthma diagnosis and symptoms of atopic eczema and wheezing in the past year.

Carsten, F, et al (2018), Effect of an Intervention to Promote Breastfeeding on Asthma, Lung Function, and Atopic Eczema at Age 16 Years, doi:10.1001/jamapediatrics.2017.4064

Assessing the health benefits and risks of the introduction of peanut and hen’s egg into the infant diet before six months of age in the UK

This review of evidence from the Scientific Advisory Committee on Nutrition (SACN) and the Committee on Toxicity (COT) explored whether peanut and hen’s egg should be introduced to an infant’s diet before six months in order to reduce the risk of developing food allergies. They concluded that there was not enough evidence to support this early introduction, reinforcing current recommendations to exclusively breastfeed for 6 months and to only introduce solids around 6 months of age. They also noted that the deliberate exclusion of peanut or hen’s egg beyond six to twelve months of age may increase the risk of allergy to the same foods. Once introduced, and where tolerated, these foods should be part of the infant’s usual diet, to suit both the individual child and family.

SACN/COT Working Group (2017), Assessing the health benefits and risks of the introduction of peanut and hen’s egg into the infant diet before six months of age in the UK.

Hydrolysed formula and allergies

This study sought to determine whether feeding infants with hydrolysed formula reduces their risk of allergic or autoimmune disease. The findings do not support current guidelines that recommend the use of hydrolysed formula to prevent allergic or autoimmune disease in high risk infants.

Boyle, R (2016), Hydrolysed formula and risk of allergic or autoimmune disease: systematic review and meta-analysis. BMJ DOI: http://dx.doi.org/10.1136/bmj.i974

Breastfeeding and asthma and allergies

This study systematically reviewed the association between breastfeeding and childhood allergic disease. The authors found some evidence that breastfeeding is protective for asthma (5–18 years). There is weaker evidence for a protective effect for eczema ≤2 years and allergic rhinitis ≤5 years of age, with greater protection for asthma and eczema in low-income countries.

Lodge, C.J. et al (2015) Breastfeeding and asthma and allergies: a systematic review and meta-analysis. Acta Paediatrica, Special Issue: Impact of Breastfeeding on Maternal and Child Health. Volume 104, Issue Supplement S467, pages 38-53. 

Infant nutrition and atopic disease

This American review found evidence that breastfeeding for at least 4 months, compared with feeding formula made with intact cow milk protein, prevents or delays the occurrence of atopic dermatitis, cow milk allergy, and wheezing in early childhood.

Greer et al. (2008) Effects of early nutritional interventions on the development of atopic disease in infants and children. PEDIATRICS; 121 (1): 183-191

Breastfeeding duration and atopic dermatitis and asthma

This German study found that a longer breastfeeding duration reduces the risk of allergies in early childhood, and linked this protective effect to the concentration of soluble CD14 in breastmilk.

Rothenbacher D et al (2005). Breastfeeding, soluble CD14 concentration in breast milk and risk of atopic dermatitis and asthma in early childhood: birth cohort study. Clin Exp Allergy 35: 1014-21.

Breastfeeding reduces the risk of five types of allergic disease

This study of 4,089 infants in Sweden found that breastfeeding had a preventive effect on the early development of five allergic diseases: asthma, suspected allergic rhinitis, atopic dermatitis, food allergy related symptoms, and suspected allergic respiratory symptoms after exposure to pets or pollen.

Kull I et al (2002). Breast feeding and allergic diseases in infants–a prospective birth cohort study. Arch Dis Child 87: 478-481.

Exclusive breastfeeding and allergies

An investigation among 2,195 children followed up to age 6 years concludes that less exclusive breastfeeding leads to increases in child asthma and atopy.

WH Oddy, JL Sherriff, NH de Klerk, GE Kendall, PD Sly, LJ Beilin, KB Blake, LI Landau, and FJ Stanley. The relation of breastfeeding and body mass index to asthma and atopy in children: a prospective cohort study to age 6 years. Am J Public Health, 2004; 94: 1531-7

Breastfeeding and allergy protection

This review of 132 studies concluded that breastfeeding seems to protect from the development of atopic disease. The effect appears even stronger in children with atopic heredity.

J van Odijk et al (2003). Breastfeeding and allergic disease: a multidisciplinary review of the literature (1966-2001) on the mode of early feeding in infancy and its impact on later atopic manifestations. Allergy 58(9): 833-43.