Allergies, overweight, and other conditions

Infant health research

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The research below explores allergies, overweight, and other conditions.

Quantitative impact of frenotomy on breastfeeding: a systematic review and meta-analysis

This systematic review and meta-analysis showed that breastfeeding self-efficacy, maternal pain, infant latch, and infant gastroesophageal reflux significantly improve after frenotomy in mother-infant dyads with breastfeeding difficulties and ankyloglossia. Providers should offer frenotomy to improve breastfeeding outcomes in symptomatic mother-infant dyads who face challenges associated with ankyloglossia.

Cordray H, Raol N, Mahendran G (2024) Quantitative impact of frenotomy on breastfeeding: a systematic review and meta-analysis. Paeditri Res. 95 (1) 34-42: https://pubmed.ncbi.nlm.nih.gov/37608056/

Systematic review of the evidence for resolution of common breastfeeding problems-Ankyloglossia (Tongue Tie)

This systematic review and meta-analysis aims to examine the effectiveness of tongue-tie treatment on breastfeeding difficulties. Six studies on tongue-tie division were included (4 randomised and 2 non-randomised). Meta-analysis of standardised mean differences in breastfeeding difficulty scores in four studies showed statistically significant differences in favour of frenotomy (Pooled SMD +2.12, CI:(0.17-4.08)p = 0.03). Similarly, a statistically significant difference in favour of frenotomy was observed for pain (Pooled SMD -1.68, 95% CI: (-2.87- -0.48). Results support that infant frenotomy is effective for improving standardised scores on breastfeeding difficulty and maternal pain scales and could improve breastfeeding outcomes.

Bruney T, Scime N, Madubueze et al (2022) Systematic review of the evidence for resolution of common breastfeeding problems – Ankyloglossia. Acta Paediatr. Vol 111(5). Pg 940-947. https://pubmed.ncbi.nlm.nih.gov/35150472/

The association between duration of breastfeeding and childhood asthma outcomes

Longer duration of exclusive breastfeeding was found to protect against child asthma according to this study which used multivariable logistic regression to analyse breastfeeding duration and child asthma outcomes at age 4 to 6 years from women involved in the ECHO PATHWAYS consortium of prospective pregnancy cohorts.  The duration of any breastfeeding had a protective linear trend with asthma, but no other outcomes. For exclusive breastfeeding, there was a duration-dependent protective association present which were stronger in dyads with children born by vaginal vs caesarean delivery, although interactions did not reach statistical significance.

Wilson, K. et al. 2022. The association between duration of breastfeeding and childhood asthma outcomes. Annals of Allergy, Asthma and Immunology. DOI:https://doi.org/10.1016/j.anai.2022.04.034

Systematic review and meta-analysis of breastfeeding and later overweight or obesity expands on previous study for World Health Organization

This review provided an update to a systematic review and meta-analysis of the association of breastfeeding with overweight or obesity that had been commissioned by the World Health Organization. A total of 159 studies were assessed, with findings concluding that breastfeeding reduced the odds of overweight or obesity, and that this association was unlikely to be due to publication bias and residual confounding.

Horta, BL, Rollins, N, Dias, MS, Garcez, V, Pérez-Escamilla, R. Systematic review and meta-analysis of breastfeeding and later overweight or obesity expands on previous study for World Health Organization. Acta Paediatr. 2022; 00: 1– 8. https://doi.org/10.1111/apa.16460

Frequency of guideline-defined cow’s milk allergy symptoms in infants: Secondary analysis of EAT trial data

Conclusions from a secondary analysis of the Enquiring About Tolerance (EAT) randomised controlled trial indicate that guideline defined symptoms of non-IgE cow’s milk allergy are very common in infants, thereby having the potential to promote milk allergy over-diagnosis by labelling normal infant symptoms as possible milk allergy.

Vincent, R. et al. 2021. Frequency of guideline-defined cow’s milk allergy symptoms in infants: Secondary analysis of EAT trial data. DOI: 10.1111/cea.14060

Breastfeeding in the First Days of Life Is Associated With Lower Blood Pressure at 3 Years of Age

A total of 2382 children with complete data on early life feeding and blood pressure were analysed in this CHILD (Canadian Healthy Infant Longitudinal Development) Cohort Study, with findings indicating that any breastfeeding, regardless of duration or exclusivity, is associated with lower blood pressure at 3 years of age. Among breastfed children, there was no significant dose‐response association according to the duration or exclusivity of breastfeeding.

Miliku, K., Moraes, T., et al. (2021). Breastfeeding in the First Days of Life Is Associated With Lower Blood Pressure at 3 Years of Age. Journal of the American Heart Association. 2021;10:e019067

Allergy societies and the formula industry

From the early years, the formula industry aligned itself with allergists and other trusted sources of infant feeding information, leading to widespread inappropriate guidance for infant feeding and false promotion of special health-promoting properties of formula. Hydrolysed formula has been inappropriately recommended for allergy prevention for over 30 years and there is excessive consumption of specialised formula in some regions due to milk allergy overdiagnosis. Formal analysis of allergy societies’ relationships with formula companies has not yet been undertaken, but it is likely that most societies and many conferences and educational activities are sponsored by formula companies. This article discusses the World Allergy Organization’s alignment with the formula industry and calls on them to follow WHO guidance, protect the patients that their members serve and stop accepting funding from formula companies.

Boyle, RJShamji, MHAllergy societies and the formula industryClin Exp Allergy2021511260– 1261. https://doi.org/10.1111/cea.14017

Breastfeeding and the developmental origins of mucosal immunity: how human milk shapes the innate and adaptive mucosal immune systems

This review summarises current knowledge and new discoveries about human milk and mucosal immunity, including how certain microbes in maternal milk seed and shape the infant gut microbiota which helps to regulate gut barrier integrity and training of the developing immune system. Human milk oligosaccharides have been shown to directly modulate gene expression in mast and goblet cells in the gastrointestinal tract, with data showing a reduced risk of peanut sensitisation among infants breastfed by peanut-consuming mothers, thereby suggesting a role for milk-borne food antigens in tolerance development. Finally, interest in human milk antibodies surged during the pandemic with the identification of neutralizing severe acute respiratory syndrome coronavirus 2 antibodies in maternal milk following both natural infection and vaccination. In summary, human milk provides critical immune protection and stimulation to breastfed infants.

Dawod, Bassela,b; Marshall, Jean S.a,b; Azad, Meghan B.c,d,e Breastfeeding and the developmental origins of mucosal immunity: how human milk shapes the innate and adaptive mucosal immune systems, Current Opinion in Gastroenterology: November 2021 – Volume 37 – Issue 6 – p 547-556 doi: 10.1097/MOG.0000000000000778

Enabling children to be a healthy weight – what we need to do better in the first 1,000 days

A new report from First Steps Nutrition Trust identifies key actions needed to protect children from overweight and obesity in the first 1,000 days of life, including requiring services to become Baby Friendly accredited. The report outlines 18 key actions needed to promote a healthy weight in the early years, including increasing investment in universal breastfeeding support, regulating the misleading commercial influence of food and drinks for infants and young children, and offering greater support for families to practise age-appropriate introduction of solids and responsive feeding.

Read more on this report here.

Infant feeding and growth trajectories in early childhood: the application and comparison of two longitudinal modelling approaches

Two longitudinal approaches revealed similar findings that infant feeding mode (breastfeeding, mixed feeding, formula feeding) and breastfeeding duration, but not the timing of solid foods introduction, were associated with BMI z-score trajectory in early childhood. The findings provide robust longitudinal evidence to encourage and support extended breastfeeding for childhood obesity prevention.

Zheng M, Campbell KJ, Baur L, Rissel C, Wen LM. Infant feeding and growth trajectories in early childhood: the application and comparison of two longitudinal modelling approaches. Int J Obes (Lond). 2021 Jul 6. doi: 10.1038/s41366-021-00892-5. Epub ahead of print. PMID: 34230577.

Barriers and enablers to caregivers’ responsive feeding behaviour: A systematic review to inform childhood obesity prevention

Responsive infant feeding is a critical component of childhood obesity prevention. This review identifies the barriers and enablers to caregiver responsive feeding. Findings indicated that parents’ recognition of a child’s feeding and safety cues are key to the development of responsive feeding, and that caregivers and infants learning to signal to each other is highly important. Therefore, the provision of timely information and education to support caregivers is critical.

Redsell, SASlater, VRose, JOlander, EKMatvienko‐Sikar, KBarriers and enablers to caregivers’ responsive feeding behaviour: A systematic review to inform childhood obesity preventionObesity Reviews2021;e13228.  https://doi.org/10.1111/obr.13228

Longer term breastfeeding and later introduction of solids associated with lower BMI in children up to five years of age

This Australian study examined the relative impact of breastfeeding duration and timing of solids introduction on BMI score in early childhood. Results demonstrated that children who were breastfed for ≥ 6 versus < 6 months had a lower BMI at all ages from three to 60 months and children who received solids before versus after six months of age had a higher BMI at 18 and 42 months.

Zheng et al. Early Infant Feeding and BMI Trajectories in the First 5 Years of Life. doi/10.1002/oby.22688. 

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

UK in danger of failing a generation of children and young people, says new report

The RCPCH published State of Child Health 2020 in March 2020, making it the UK’s largest compilation of data on the health of babies, children and young people. The report used key indicators to determine measures of health and wellbeing, including infant mortality, maternal and perinatal health, breastfeeding and smoking during pregnancy. Whilst the report confirmed that improvements in income and healthcare have contributed to a steady fall in the number of babies dying in their first year for some decades now throughout the world, conclusions found that infant mortality worsened in England between 2016-2017 and more than doubled in the most deprived areas compared to the least deprived areas of England and Wales.

Royal College of Paediatrics and Child Health. State of Child Health 2020. March 2020.

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

Breastfeeding and skin-to-skin contact as non-pharmacological prevention of neonatal hypoglycemia in infants born to women with gestational diabetes; a Danish quasi-experimental study

This study investigated the effect on infant blood glucose levels of an intervention consisting of early, frequent breastfeeding and two hours of immediate uninterrupted skin-to-skin contact following birth of term infants born to mothers with diet-treated gestational diabetes (GDM). The researchers found that infants suffering a hypoglycemic event within four hours after birth decreased from 22.7% in the control group to 10.2% in the intervention group. The mean number of breastfeeds in the intervention group (six hours) was 2.41 compared to 1.34 in the control group (seven hours), an increase of 80%.

Dalsgaard, BT, Rodrigo-Domingo, M, Kronborg, H, & Haslund, H (2019). Breastfeeding and skin-to-skin contact as non-pharmacological prevention of neonatal hypoglycemia in infants born to women with gestational diabetes; a Danish quasi-experimental study. Sexual & Reproductive Healthcare, 19: 1-8

Comparative evaluation of the effects of human breast milk and plain and probiotic-containing infant formulas on enamel mineral content in primary teeth: an in vitro study

Findings from this study indicate that breastmilk may have protective effects against the demineralisation of infant teeth, with results showing an increased mean calcium wt% when soaked in breastmilk for one week. In comparison, plain and supplemented infant formula promoted mineral loss from enamel surface.

Aly AAM, Erfan D, Abou El Fadl RK. Comparative evaluation of the effects of human breast milk and plain and probiotic-containing infant formulas on enamel mineral content in primary teeth: an in vitro study. Eur Arch Paediatr Dent. 2020 Feb;21(1):75-84. doi: 10.1007/s40368-019-00448-2. Epub 2019 May 23. PMID: 31124082.

Breastfeeding in infancy and lipid profile in adolescence

This study explored whether there was an association between breastfeeding in the first three months of life with lipid profile and adiposity at around 17.5 years. The researchers included 3,261 participants in the Hong Kong Chinese birth cohort Children of 1997, adjusting for sex, birth weight, gestational weeks, parity, pregnancy characteristics, parents’ highest education, mother’s place of birth, and age at follow-up. They found that exclusive breastfeeding, but not mixed feeding at 0 to 3 months, compared with formula feeding was associated with lower total cholesterol and low-density lipoprotein cholesterol but not with high-density lipoprotein cholesterol at ∼17.5 years. BMI and fat percentage measured by bioimpedance did not differ by type of infant feeding.

L.L. Hui, Man Ki Kwok, E. Anthony S. Nelson et al (2019). Breastfeeding in Infancy and Lipid Profile in Adolescence. Pediatrics, Volume 143, Issue 5.

Effects of opaque, weighted bottles on maternal sensitivity and infant intake

This study explored whether use of opaque, weighted bottles (as compared with conventional, clear bottles) improves feeding outcomes by supporting responsive bottle feeding and reducing over feeding. The researchers found that when using the opaque bottles, mothers exhibited significantly greater sensitivity during feeding, fed their infants fewer millilitres per kilogram body weight, and fed their infants at a significantly slower rate. They note that infant clarity of cues was a significant moderator of effects of bottle type on intake per kilogram body weight, and that effects of bottle type were not moderated by bottle contents (expressed breast milk vs. formula). They concluded that promotion of opaque, weighted bottles for infant feeding may be a pragmatic approach to improve the quality and outcome of bottle‐feeding interactions.

Ventura, A, & Hernandez, A, (2018). Effects of opaque, weighted bottles on maternal sensitivity and infant intake, Maternal & Child Nutrition, doi.org/10.1111/mcn.12737

Infant feeding and weight gain: Separating breast milk from breastfeeding and formula from food

This study explored the link between feeding method and weight, using feeding reports from mothers and hospital documents, and measuring weight and BMIz scores at 12 months. Compared with exclusive direct breastfeeding at 3 months, all other feeding styles were associated with higher BMIzs. Formula supplementation by 6 months was associated with higher BMIzs, whereas supplementation with solid foods was not. Results were similar for weight gain velocity. The authors concluded that breastfeeding is inversely associated with weight gain velocity and BMI. These associations are dose dependent, partially diminished when breast milk is fed from a bottle, and substantially weakened by formula supplementation after the neonatal period.

Azad, M B, Vehling, L, and Chan, D (2018). Infant feeding and weight gain: separating breast milk from breastfeeding and formula from food. Pediatrics, DOI: 10.1542/peds.2018-1092

Effect of a responsive parenting educational intervention on childhood weight outcomes at 3 years of age

This study examined effects of a responsive parenting intervention designed to promote developmentally appropriate, prompt, and contingent responses to a child’s needs on weight outcomes at 3 years. Researchers found that, among primiparous mother-child dyads, a responsive parenting intervention initiated in early infancy compared with a control intervention resulted in a modest reduction in BMIz scores at age 3 years, but no significant difference in BMI percentile. Further research is needed to determine the long-term effect of the intervention and assess its efficacy in other settings.

Paul, I, Savage, J, and Anzman-Frasca, S, (2018). Effect of a responsive parenting educational intervention on childhood weight outcomes at 3 years of age. JAMA, doi:10.1001/jama.2018.943

Early infant feeding of formula or solid foods and risk of childhood overweight or obesity in a socioeconomically disadvantaged region of Australia: A longitudinal cohort analysis

This Australian study of 346 singleton, full term and normal weight infants measured the outcome risk of overweight or obesity at every two-year interval of children aged 0 or 1 year at baseline until they reached age 10 or 11, defined by body mass index (BMI) ≥ 85th percentile. Researchers found that the odds of overweight or obesity were significantly higher among infants introduced to formula or solids at ≤4 months compared to those introduced at >4 months. The odds of overweight or obesity when age at formula or solids introduction was held fixed at ≤4 months, increased significantly for children stopping breastfeeding at age ≤4 months compared to >4 months. The authors concluded that increasing the prevalence of breastfeeding without any formula or solids to 4–6 months in southwest Sydney should be a worthwhile public health measure.

Mannan, H, (2018). Early infant feeding of formula or solid foods and risk of childhood overweight or obesity in a socioeconomically disadvantaged region of Australia: A longitudinal cohort analysis. Int. J. Environ. Res. Public Health, doi:10.3390/ijerph15081685

Association of exposure to formula in the hospital and subsequent infant feeding practices with gut microbiota and risk of overweight in the first year of life

This study found that among 1,087 infants from the Canadian Healthy Infant Longitudinal Development (CHILD) cohort, earlier cessation of breastfeeding and supplementation with formula (more so than complementary foods) were associated with a dose-dependent increase in risk of overweight by age 12 months; this association was partially explained by specific gut microbiota features at 3 to 4 months. Subtle but significant microbiota differences were observed after brief exposure to formula limited to the birth hospital stay, but these differences were not associated with overweight.

Forbes, J, Azad, B, et al, (2018). Association of Exposure to Formula in the Hospital and Subsequent Infant Feeding Practices With Gut Microbiota and Risk of Overweight in the First Year of Life. JAMA Paediatrics, doi:10.1001/jamapediatrics.2018.1161

Human Milk Oligosaccharides Exhibit Antimicrobial and Antibiofilm Properties against Group B Streptococcus

This study examined how human milk oligosaccharides (HMOs) affect the pathogenesis of Group B Streptococcus (GBS). Researchers found that HMOs affect the growth and cell biology of GBS, providing the first example of HMOs functioning as antibiofilm agents against GBS – not only destroying bacteria directly but also physically breaking down the biofilms that the bacteria form to protect themselves.

Ackerman, DL, et al (2017), Human Milk Oligosaccharides Exhibit Antimicrobial and Antibiofilm Properties against Group B Streptococcus, ACS Infectious Diseases, DOI: 10.1021/acsinfecdis.7b00064

Blog: Breastfeeding after 12 months and dental decay

In this blog post, Emma Pickett, Breastfeeding counsellor & IBCLC and Chair of the Association of Breastfeeding Mothers, analyses claims that breastfeeding after 12 months promotes dental decay in babies and young children and highlights how these messages are often based on low-quality evidence and studies. A statement from Public Health England (2019) is included which reads: “Breastfeeding is the physiological norm against which other behaviours are compared; therefore, dental teams should promote breastfeeding and include in their advice the risks of not breastfeeding to general and oral health … Since 2001 the WHO has recommended that mothers worldwide exclusively breastfeed infants for the first six months to achieve optimal growth, development and health. Thereafter, they should be given nutritious complementary foods as breastfeeding continues up to the age of two years or beyond. These guidelines were reiterated in the WHO’s Global Strategy (WHO, 2003) and endorsed by the Scientific Advisory Committee on Nutrition (SACN).”

Read more on Emma Pickett’s blog here. 

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