Research into the effects of early introduction of allergens on later development of allergy May 2010

The World Health Organization (WHO) Global Strategy for Infant and Young Child Feeding, endorsed by the UK Government, recommends exclusive breast feeding for the first 6 months. 

The UK Government weaning information leaflet for parents advises 6 months exclusive breast feeding. It also states that if a mother decides to wean before six months there are some foods that should be avoided in this early period of weaning as they may cause allergies including: “wheat-based foods and other foods containing gluten (e.g. bread, rusks, some breakfast cereals), eggs, fish, shellfish, nuts (and) seeds".

There is little evidence that avoiding these allergens at an early age prevents allergy. Research studies that set out to find out if delayed weaning reduces food allergy show conflicting results.  Moreover, there is some emerging evidence that suggests that the early introduction of allergenic foods may actually protect against the development of food allergy, but this has yet to be confirmed. The theory is that repeated exposure of the immune system at an early age to an allergenic food via the oral route (in other words, eating the food), teaches the body to tolerate the food so it will not cause an allergy when the child grows older.

The EAT Study (Enquiring About Tolerance) is researching this specific area and although it will be some years before the restults are available, further detail about the study can be found here : EAT Study.

The second of the research projects in this area is entitled the 'LEAP' Study (Learning About Peanut Allergy).  It is a clinical trial learning how best to prevent peanut allergy in young children.  Further information about the LEAP Study can be found here: LEAP Study