Giving babies eggs and nut products early may avert allergies
Timing of gluten introduction didn't have any impact on whether kids developed celiac disease
These findings suggest that for most babies, eggs and peanuts should be among their first foods, said senior study author Dr. Robert Boyle, a pediatric allergy researcher at Imperial College London.
Feeding guidelines have moved away from telling parents to avoid introducing some foods that can cause allergies until kids are 2 or 3 years old, but most recommendations still stop short of urging parents to give babies eggs and peanuts early in life.
- Food allergies in infants may be prevented with early introduction
- Peanuts for babies? Studies back allergy-preventing strategy
To see how the timing of babies' introduction to certain allergenic foods influences their risk of allergies, Boyle and colleagues reviewed data from 146 studies published over the past 70 years.
When 5.4 per cent of the population has egg allergies, early introduction could avoid 24 cases for every 1,000 people, a review of data from five of those studies with 1,915 participants found.
For peanuts, when about 2.5 per cent of the population has allergies, early introduction could avoid 18 cases for every 1,000 people, a review of data 1,550 participants found.
They also looked at whether giving babies gluten, a protein in wheat, rye and barley, early might increase the risk of celiac disease, an autoimmune disorder that damages the small intestine and interferes with the absorption of nutrients from food.
In addition, researchers found no evidence that the timing of introduction of allergenic foods like eggs, peanuts and fish influenced the odds of developing other autoimmune disorders such as Type 1 diabetes.
One limitation of the analysis is that individual studies had different designs and populations, making it hard to draw broad conclusions that could apply to all children, the authors note in JAMA.
Early introduction of potentially allergenic foods may not be a panacea in preventing allergies, Dr. Matthew Greenhawt, a researcher at the University of Colorado School of Medicine in Aurora writes in an accompanying editorial.
Consult a doctor for at-risk kids
"Most children are not at risk for developing food allergy and thus, they wouldn't need any specific intervention or supervision," Greenhawt said.
Parents of at-risk kids should consult a doctor or allergy specialist before introducing foods that can trigger an allergic reaction, Greenhawt added.
And of course, a 4-month-old can choke on whole peanuts, and should get this food in peanut butter form.
"I do think that the findings suggest a need to consider changes to clinical practice," Hong said by email. "Food allergies have the potential to result in life-threatening reactions."