There is uncertainty regarding the prevalence of allergies to plant food.
To assess the prevalence of allergies to plant food according to the different subjective
and objective assessment methods.
Our systematic search of population-based studies (since 1990) in the literature database
MEDLINE focused on fruits, vegetables/legumes, tree nuts, wheat, soy, cereals, and
seeds. Prevalence estimates were categorized by food item and method used (food challenges,
skin prick test, serum IgE, parent/self-reported symptoms), complemented by appropriate
meta-analyses.
We included 36 studies with data from a total of over 250,000 children and adults.
Only 6 studies included food challenge tests with prevalences ranging from 0.1% to
4.3% each for fruits and tree nuts, 0.1% to 1.4% for vegetables, and < 1% each for
wheat, soy, and sesame. The prevalence of sensitization against any specific plant
food item assessed by skin prick test was usually < 1%, whereas sensitization assessed
by IgE against wheat ranged as high as 3.6% and against soy as high as 2.9%. For fruit
and vegetables, prevalences based on perception were generally higher than those based
on sensitization, but for wheat and soy in adults, sensitization was higher. Meta-analyses
showed significant heterogeneity between studies regardless of food item or age group.
Population-based prevalence estimates for allergies to plant products determined by
the diagnostic gold standard are scarce. There was considerable heterogeneity in the
prevalence estimates of sensitization or perceived allergic reactions to plant food.