Peanuts allergies are one of the most prevalent types of food allergies and are capable of causing life-threatening anaphylactic reactions. Peanut allergies are commonly diagnosed in children less than 2 years old, and are the food allergy least likely resolve with age. A recent review by Bunyavanich et al. looked at diagnoses of peanut allergies between 1997 and 2007 and found that in children under the age of 18, the prevalence of the peanut allergy more than doubled, and since then, the upward trend has continued, an estimated twenty percent. Experts predict that this number will continue to rise, though the exact reason for this increase is unclear. There have been some studies to suggest that lifestyle may play a role. A 2012 study found a higher incidence of food allergies in children living in cities compared to more rural areas.
Peanut allergies have created substantial social difficulties. Because of the potential severity of the reaction, many schools have banned all kinds of peanut products from schools, while psychology experts have proposed that children with food allergies have a more difficult time making friends and assimilating into their class. Other studies show that there is an economic impact: families that have one or more members with a food allergy spend on average $1,000 more on food each year. Outside of social difficulties, studies have found that food allergies including peanut allergies can lead to growth defects in children, and a study on quality of life found that parents of children with food allergies suffered more anxiety and a decreased quality of life compared with parents of allergy-free children.