Diet and Atopic Dermatitis
Dermatologists and pediatric dermatologists frequently treat patients with atopic dermatitis (AD), and patients and guardians often associate AD with food allergies. A common misconception is that dietary restrictions will resolve the disease. The role of diet is evolving in the discussion of AD. The American Academy of Dermatology (AAD) has recently provided recommendations on diet and therapies for AD. This article reviews recent scientific data on the role of foods and dietary modifications in the management of AD as both an intervention and as prevention.
Practice Points
- Test children younger than 5 years with moderate to severe atopic dermatitis (AD) for food allergies if they have persistently severe AD or known food-induced reactions.
- Food elimination diets are not recommended for management of AD.
- There is not enough evidence supporting the use of complementary and alternative medicine, probiotics/prebiotics, or supplements for the treatment of AD.
Risks of Dietary Restriction
Dietary restrictions in treating AD can have negative consequences, including reduced birth weight when initiated in pregnancy,19 osteomalacia from vitamin D deficiency,44 and nutritional deficiencies (eg, calcium, phosphorus, iron, vitamin K, vitamin D, zinc, vitamin A, B1, B2, B6, niacin, cholesterol, and/or vitamin C deficiencies).45 Excess dietary intake of vegetables in individuals with extensive food allergies can result in carotenemia.46 Protein-restricted diets from use of rice milk or dietary protein restriction can result in kwashiorkorlike protein malnutrition and marasmus.47-49 Nutritional counseling and/or supplementation is recommended for patients with food-restricted diets.
Avoiding Fragrance in Food
Food intolerance often is reported by AD patients. In allergies, food intolerance refers to side effects such as gastrointestinal symptoms; in dermatology, food intolerance can include itching, systemic flares of allergic contact dermatitis (eg, fragrance allergy), or true IgE-mediated allergies such as oral allergy syndrome. Oral allergy syndrome (pollen-food allergy syndrome) is an epitope-spread phenomenon related to an allergy to tree pollen, causing broad allergy to specific groups of fruits and nuts.50 Food triggers in AD include kiwi, milk, apple, tomato, citrus fruits, tree nuts, and peanuts. Oral allergy syndrome is common in food-sensitive AD patients (51.2%) followed by gastrointestinal symptoms (23.5%) and worsening AD (11.4%).51 Sensitization to fragrance can cross-react with foods (eg, balsam of Peru and tomatoes).52 A tomato allergy can be detected either by a skin-prick test or a food patch test in this setting.53 An allergist should be consulted if oral allergy syndrome is suspected.
Conclusion
Food allergies are more common in AD patients and patients should be referred to an allergist for evaluation and management. Strict dietary practice is not recommended, while avoiding proven food allergens in AD could be beneficial. Dermatologists should be aware that patients with dietary restrictions may lack key nutrients, manifesting with nutritional deficiencies in the skin; therefore, nutrition counseling may be needed in the most severe AD/allergy patients. This field is evolving; therefore, ongoing study and evaluation of interventions as they relate to AD will be needed to assess best practices for diet in AD over time.
