Feeding foods like peanut, egg, and milk only once or twice is NOT effective in preventing food allergies. Studies have shown that early allergen introduction is most effective when done regularly for at least 6 months. In the largest study (LEAP), parents who quit before 3 months did not benefit. That's why we recommend using Ready, Set, Food! for 6 months, or until your baby is regularly eating peanut, egg, and milk at least 3 times per week.
Learn more about why once is not enough here.