Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy

Received 30 June 2008; received in revised form 20 August 2008; accepted 25 August 2008.

Background

Despite guidelines recommending avoidance of peanuts during infancy in the United Kingdom (UK), Australia, and, until recently, North America, peanut allergy (PA) continues to increase in these countries.

Objective

We sought to determine the prevalence of PA among Israeli and UK Jewish children and evaluate the relationship of PA to infant and maternal peanut consumption.

Methods

A clinically validated questionnaire determined the prevalence of PA among Jewish schoolchildren (5171 in the UK and 5615 in Israel). A second validated questionnaire assessed peanut consumption and weaning in Jewish infants (77 in the UK and 99 in Israel).

Results

The prevalence of PA in the UK was 1.85%, and the prevalence in Israel was 0.17% (P < .001). Despite accounting for atopy, the adjusted risk ratio for PA between countries was 9.8 (95% CI, 3.1-30.5) in primary school children. Peanut is introduced earlier and is eaten more frequently and in larger quantities in Israel than in the UK. The median monthly consumption of peanut in Israeli infants aged 8 to 14 months is 7.1 g of peanut protein, and it is 0 g in the UK (P < .001). The median number of times peanut is eaten per month was 8 in Israel and 0 in the UK (P < .0001).

Conclusions

We demonstrate that Jewish children in the UK have a prevalence of PA that is 10-fold higher than that of Jewish children in Israel. This difference is not accounted for by differences in atopy, social class, genetic background, or peanut allergenicity. Israeli infants consume peanut in high quantities in the first year of life, whereas UK infants avoid peanuts. These findings raise the question of whether early introduction of peanut during infancy, rather than avoidance, will prevent the development of PA.

Key words: Allergy, children, food allergy, peanut allergy, prevalence, allergy prevention, oral tolerance, weaning, peanut consumption

Abbreviations used: FAQ, Food Allergy Questionnaire, FFQ, Food Frequency Questionnaire, PA, Peanut Allergy, RR, Relative risk, SA, Sesame allergy, TNA, Tree nut allergy, UK, United Kingdom

a King's College London, MRC and Asthma UK Centre in Allergic Mechanisms of Asthma, Division of Asthma, Allergy and Lung Biology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom

b Allergy and Immunology Institute, Assaf Harofeh Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel

c Cancer Research UK Centre for Epidemiology, Mathematics and Statistics, Wolfson Institute of Preventive Medicine, Barts, and the London School of Medicine, London, United Kingdom

d US Department of Agriculture, Agricultural Research Service, Southern Regional Research Center (SRRC), New Orleans, La

e Israel Institute of Technology, Haifa, Israel

f Allergy and Immunology Institute, Assaf Harofeh Medical Center, Tel Aviv, Israel

g School of Health and Health Education, Jerusalem, Israel

Reprint requests: Gideon Lack, FRCPCH, Kings College London, Evelina Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, Lambeth Palace Rd, London, United Kingdom SE1 7EH.

Supported by a research grant from the National Peanut Board, United States. This grant supported the project costs, including the salary of G.D.T. over the study duration. G.L.'s salary was in part supported by the Aimwell Foundation. Support was also provided by the Department of Health via the National Institute for Health Research comprehensive Biomedical Research Centre award to Guy's and St Thomas' NHS Foundation Trust in partnership with King's College London.

Disclosure of potential conflict of interest: G. Du Toit has received research support from the Immune Tolerance Network and the National Peanut Board, United States. Y. Katz has received research support from the Israel Dairy Board and has provided legal consultation or expert witness testimony on the subject of milk exposure. S. J. Maleki has received research support from the Georgia Peanut Commission. V. Turcanu has received research support from the Food Standards Agency (UK), the National Peanut Board, United States, the Immune Tolerance Network, and the Food Allergy and Anaphylaxis Network. G. Lack has consulted for the advisory boards of Synovate, Novartis-Xolair, and ALK-Abelló; has given lectures supported by SHS Nutricia, SHS International, and Nestlé; has received research support from the Immune Tolerance Network, the National Peanut Board, United States, the Food Standard Agency, the Food Allergy Initiative, the Food Allergy and Anaphylaxis Network, and the Medical Research Council; and has served as a scientific advisor for the Anaphylaxis Campaign and the National Peanut Board, United States. The rest of the authors have declared that they have no conflict of interest.

PII: S0091-6749(08)01698-9

doi:10.1016/j.jaci.2008.08.039

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