Milk elimination diets are frequently adopted in the treatment of atopic dermatitis, although the real prevalence of clinically relevant food allergy remains unclear and reports from different authors are often in disagreement. We investigated the percentage of children allergic to cow's milk compared with the rate of milk exclusion diets in a group of patients with atopic dermatitis. We enrolled 206 children (79 girls, 127 boys), mean age 45.8 (4-68) months, affected by atopic dermatitis into our study. All children underwent radioallergosorbent test for casein, alpha-lactalbumin and beta-lactoglobulin, prick test, atopy patch test, and oral provocation test. Children were followed up at 1, 3, 6, and 12 months. Of the 206 patients, 20 were excluded from statistical analysis, leaving 186. Forty-five (24.2%) were on a milk elimination diet and 141 on a normal diet. Four patients on the milk-free diet (8.9%), accounting for 2.2% of all patients, were found to be allergic. In the others, milk reintroduction did not cause the disease to worsen during the follow-up period. No children on a normal diet were found to be allergic. Our results demonstrated an actual prevalence of cow's milk allergy in patients on milk elimination diets (4%) to be significantly lower than the number of patients prescribed such diets (24.2%)-confirming that this measure is being applied excessively.