Atopic dermatitis, commonly known as eczema, is a chronic inflammatory skin condition that causes redness, itching, rashes, and can sometimes lead to skin infections. It affects approximately 20% of children in industrialized countries. Many children with eczema also have other allergic conditions, including food allergies. In this article, we’ll explore the connection between eczema and food allergies, whether one causes the other, and discuss effective strategies for managing and soothing eczema flare-ups. 

Are eczema and food allergies connected?

While eczema has been linked to food allergies, it's important to clarify that food allergies do not directly cause eczema.  In most cases, eczema develops first, particularly in infants and young children, and may actually increase the risk of developing food allergies later on. “Research suggests that eczema often precedes the development of food allergies, indicating that eczema may be a risk factor for food allergies rather than the other way around,” explains Dr. Marcy Borieux MD, FAAP, a pediatrician at Summer Health. This means that children with eczema, especially more severe cases, may be more susceptible to food allergies.

Some children with moderate to severe eczema may experience flare-ups when they consume certain allergenic foods. However, this doesn’t mean those foods caused their eczema—it simply means the allergens can aggravate an existing condition. Food allergies are now recognized as a comorbidity (coexisting health condition) of eczema.

Bottom line: Eczema and food allergies often go hand in hand, but eczema usually comes first. And while food allergens can trigger flares in some children, they do not cause eczema. 

What causes eczema?

Eczema is caused when the skin’s protective barrier doesn’t work as well as it should. Many kids with eczema don’t have enough of filaggrin, a protein which helps the outer skin layer stay strong and healthy. Without enough filaggrin, the skin has a harder time holding in moisture and keeping out things like harmful microorganisms and environmental irritants. This makes the skin dry, itchy, and more prone to inflammation and flare-ups. Eczema also tends to run in families. Many children with eczema have a parent or close relative who also has eczema.

Eczema symptoms

Eczema may look different from one child to the next. Common symptoms include:

• Rash patches, widespread or limited to a few areas

• Itchy skin

• Dry, cracked skin

• Red, inflamed skin

• Sometimes the skin becomes infected, leading to oozing, crusty blisters, or pus-filled bumps

Food allergy symptoms

Food allergy symptoms can range from mild to severe and may affect different parts of the body. Common reactions include:

• Skin symptoms: Hives, itchy or severe rash, swelling of the lips, mouth, tongue, eyes, or face

• Gastrointestinal symptoms: Vomiting, diarrhea, abdominal pain, nausea

• Respiratory symptoms: Trouble breathing, coughing, wheezing, turning blue (cyanosis), anaphylaxis.

Anything reaction that inhibits breathing, requires immediate medical attention. If you suspect your child is having a severe allergic reaction, call 911 immediately.  

Which foods cause eczema flare-ups?

Certain foods, especially the most common allergens, are known to provoke eczema flare-ups in some children. These include:

• Cow’s milk

• Eggs

• Peanuts

• Tree nuts (like almonds, walnuts, or cashews)

• Wheat

• Soy

• Fish

• Shellfish

• Sesame

It’s important to remember that not every child with eczema will react to these foods, and individual sensitivities can vary widely. If you suspect a specific food is making your child’s skin worse, it’s best to work with a pediatrician or allergist to determine if an elimination diet or testing is needed.

Other common causes of eczema flare-ups:

• Skin barrier disruptions

• Environmental irritants (soaps, detergents, chemicals)

• Weather changes (dry or cold air, humidity)

• Sweating

• Stress

A weakened gut-skin barrier is connected to eczema. The gut-skin barrier (or axis) is the interconnected relationship between your gut and your skin. A healthy gut microbiome (collections of billions of microorganisms in the gut) can positively impact skin and when the gut is out of balance, it can cause skin issues like eczema. “Both the skin and the gut have protective barriers that keep out harmful substances and help maintain a healthy balance of bacteria,” explains Borieux. “When these barriers are weakened, it becomes easier for allergens and irritants to enter the body, which can trigger the immune system to react abnormally.”

How are eczema and food allergies diagnosed?

To diagnose eczema, your child’s pediatrician will examine your child’s skin and ask questions about symptoms, medical history, and any family history of eczema, allergies, or asthma. Food allergies are diagnosed through a combination of tests, such as: 

• Skin prick test: Also known as a scratch test, your child’s pediatrician will prick your child’s skin (usually on the back or forearms) with drops of the food allergens on your child’s back and wait to see if there is a reaction like redness, swelling, or bumps at site. The skin prick test takes about 20 minutes.  

• Blood test: Your pediatrician may order a blood test to measure the levels of immunoglobulin E (IgE) antibodies to specific foods. IgE antibodies are proteins made by the immune system in response to what it sees as a threat. If you have high amounts of IgE antibodies to a specific. Elevated IgE levels in response to particular foods can suggest a food allergy, although further testing is required. 

• Oral food challenge test: This is considered the most accurate way to diagnose a food allergy and can be used on its own to confirm whether a specific food is causing symptoms. During the test, your child will eat gradually increasing amounts of the suspected allergen under close medical supervision.If no reaction occurs, it's unlikely your child is allergic to that food. However, if symptoms of an allergic reaction appear, the test confirms the presence of a food allergy. Keep in mind that most IgE-mediated food allergic reactions appear within minutes to two hours after eating the food allergen. Occasionally, some symptoms can be delayed for several hours after the exposure.

Keep in mind that food allergy tests cannot diagnose eczema. However, they can help manage eczema by identifying potential triggers.

Why is eczema common in babies and children?

Eczema often shows up in babies and young children because their skin and immune systems are still developing. “Eczema is common in babies and children due to genetic predisposition, immature skin barrier, and immaturity of their immune system,” says Dr. Borieux.  Early exposure to things like irritating chemicals, dust, pet dander, or harsh soaps or detergents trigger or exacerbate eczema symptoms.

Effective eczema treatments for children

These strategies help manage active flare-ups and also work to prevent future exacerbations:

• Consistently keep your child’s skin moisturized with a fragrance-free, thick cream or ointment. This is especially important after the bath to help lock in the moisture. 

• Give your child a short bath every day or every other day for 5 to 10 minutes, using lukewarm water. Do not use hot water or soap (including bubble bath), which can irritate the skin. Instead, use a fragrance-free and gentle non-soap cleanser to clean the body. 

• Use fragrance-free laundry detergents to wash clothing. Do not use fabric softeners or fabric sheets because they may have irritating chemicals. 

• Dress your child with breathable fabrics (like 100% cotton) to prevent sweat from building up and irritating the skin.

• Your pediatrician may prescribe topical corticosteroids creams for flare-ups, which can reduce itching and relieve inflammation and discomfort. 

FAQs

Do children outgrow eczema?

Eczema often improves with age, but can persist into adulthood. For some children, eczema starts to go away by age four. 

Is eczema contagious?

No, eczema is not contagious. 

Do probiotics help with eczema?

“Probiotics have not shown consistent benefit for eczema and are not routinely recommended,” explains Dr. Borieux. “More research is needed to confirm their effectiveness, especially in children.”

Does vitamin D relieve eczema?

Vitamin D supplementation may support the immune system, but research has not demonstrated clear benefits in reducing eczema symptoms.

Is gluten bad for eczema?

Gluten is not a common cause of eczema flare-ups unless there is a confirmed wheat allergy or celiac disease.

How do I know if a rash is related to eczema, a food allergy, or something else?

Eczema is slower to develop and a food allergy rash is a faster reaction. “A food allergy rash usually appears quickly (within minutes to two hours) after eating a certain food,” says Borieux. “It often looks like hives (raised, red, itchy bumps) and may be part of a more serious reaction, sometimes with swelling, trouble breathing, or vomiting.”

What foods should be avoided in children with eczema?

Most children with eczema do not need to avoid any specific foods unless they have a diagnosed food allergy.

Does too much sugar cause eczema?

Too much sugar does not directly cause eczema.

If you have questions about eczema or food allergies, reach out to your local or Summer Health pediatrician for support. Summer Health is a pediatric telehealth platform offering 24/7 care, providing answers for everything from urgent concerns to everyday questions about your child’s health.