So, as a proud father of a two-months old daughter, whose mom has many rather strong allergies and heavy asthma passed down through several generations we'd like to suppress her developing of allergies and especially asthma as far as possible. However, I kind of get conflicting information on the best path towards allergy prevention (or suppression):
Our midwife tells us that long duration of exclusive breastfeeding is best to prevent allergies. Indeed, this study (Ekelund et al. 2021): https://internationalbreastfeedingjournal.biomedcentral.com/articles/10.1186/s13006-020-00352-2 finds that long duration of breastfeeding can improve wheeze and allergic rhinoconjunctivitis (ARC) but not asthma or eczema If I read the paper correctly, the study doesn't evaluate for exclusive breastfeeding though. Anyways, while inconclusive for asthma and eczema, wheeze seems to be a factor for developing asthma: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5408007/ Since the study didn't target parents and children with genetic predisposition towards asthma, I guess that the inconclusivity towards asthma might be due to a too small number of participants (~6800).
On the other hand, allergenic foods e.g. peanuts (my wife is extremely allergic to those), should be done no less than after 4-6 months (Trogen et al. 2022): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9268235/ They write:
Until 2008, clinical practice guidelines from the American Academy of Pediatrics (AAP) and other professional societies recommended delaying the introduction of allergenic foods, such as peanut, until 3 years of age. This recommendation was based on the theory that the lack of exposure to allergenic foods during early infancy—which was posited to be a developmental window of high susceptibility—would prevent later development of allergy.
Now obviously, the introduction to allergenic foods should happen earlier if the child develops eczema, with the idea that intact allergenic proteins sensitize the immune system faster through the destroyed skin barrier than through ingestion, because the proteins get degraded through the gastric acid and become thus less allergenic.
This leads me to the following question:
- Besides the obvious fact that the gut flora is not yet fully developed, why not start giving solid food already in month e.g. 2 or 3?
- Why has the theory of delaying allergenic food come up at all? There should be at least a plausible scientific hypothesis behind this argumentation, shoudn't it?
Thanks a lot!
(These posts are likely related:
Does early exposure protect against developing allergies later on in life?
Rising allergy and intolerance diagnosis rates
Can foods one is not allergic to exacarbate atopic dermatitis?)