Ask an expert: What foods can cause an allergic reaction and itchy skin?

If you have a food allergy that causes itchy skin and other unpleasant symptoms, you’re not alone. Food allergies are quite common—in the United States, studies show they affect roughly 11% of adults.¹ They’re often caused by exposure to specific proteins in foods, which the immune system identifies as invaders and produces antibodies to fight them off.² That can result in unpleasant symptoms, like redness and itchy skin. 

Allergies aren’t curable, but they are manageable. When it comes to food allergies, specifically, identifying potential allergens in your diet is the best way to keep those irritating—and potentially dangerous—symptoms at bay. Here we’ll tell you everything you need to know to help you avoid itchy, uncomfortable skin reactions.

Types of food allergies 

There are two main types of food allergies: Immunoglobulin E (IgE) mediated and non-lgE mediated. When you have an IgE mediated food allergy, your body’s immune system makes IgE antibodies that react to certain foods. These allergic reactions usually happen within a few minutes to several hours of consuming the food allergen in question and can include mild-to-severe symptoms, like anaphylaxis, which is a serious and potentially life-threatening acute allergic reaction. When you have a non-IgE food allergy, your immune system does not produce IgE antibodies. However, other parts of your immune system respond to the perceived threat. These allergic reactions tend to be more delayed, usually 24-48 hours after consuming the food allergen.³

6 foods that may trigger itchy skin 

It’s important to remember that everyone is different, and the specific foods that cause allergic reactions vary from person to person. If you have dietary allergies, there’s no exhaustive list of foods to avoid—for itchy skin and other reactions. But here are some of the more common ones:

Milk

Being allergic to cow’s milk is common, particularly in babies and children. The usual culprits are whey and casein, two types of protein in cow's milk. This allergy can cause various signs and symptoms, including wheezing, itching, cramps, tongue swelling, diarrhea, vomiting, anaphylaxis, and more⁴ (dairy is also linked to acne in some people). 

Eggs

This allergy is caused by the proteins found in the whites or yolks of chicken eggs including ovomucin, ovalbumin, ovotransferrin, and egg white lysozyme, and studies suggest there may be a genetic component as well. Egg allergy symptoms can include hives, which cause red, itchy skin, as well as stomach pain, vomiting, and diarrhea.⁵

Peanuts

This is one of the most common—and potentially fatal—food allergies. Symptoms of allergic reactions to peanuts can include skin reactions, wheezing, swelling, digestive issues, and shortness of breath. Life-threatening anaphylaxis can also occur in severe cases. Peanut allergies are typically lifelong, and studies show that a history of eczema is a risk factor.⁶

Shellfish

Shellfish are a type of seafood with hard shells or shell-like exteriors, like shrimp, prawns, crabs, lobsters, and squids. Allergies to these crustaceans can be caused by variable proteins such as tropomyosin and can result in itching, hives, wheezing, gastrointestinal symptoms, and, in some cases, anaphylaxis.⁷

Wheat

Wheat allergen can activate either IgE mediated or  non-IgE immune responses. There are several proteins in wheat that can be the culprits, and symptoms can include itching, digestive problems, respiratory problems, and in severe cases, anaphylaxis. Wheat allergies are more common in children. If you’re allergic to wheat, it’s recommended to cut out foods that contain it.⁸

Tree Nuts

Allergies to pecans, cashews, almonds, hazelnuts, and any tree nut containing proteins like oleosins, legumin, vicilins, and 2S albumins are also common.⁹ Symptoms can include itchiness, tingling, skin redness, and mouth swelling.¹⁰ Conditions like eczema and asthma are associated with more severe tree nut allergies.

Other common food allergy symptoms 

The symptoms of a food allergy can take a few moments, hours, or days to emerge, depending on the type of allergy. Food allergy symptoms range from mild to severe, and, in some cases, they can be life-threatening. Food allergy symptoms can include the following:

• Itching 

• Rash 

• Swelling of the tongue or mouth 

• Swelling of the face

• Hives

• Eczema 

• Watery eyes

• Runny nose 

• Gastrointestinal issues, including vomiting and diarrhea 

• Difficulty breathing

• Respiratory problems 

• Low blood pressure

• Anaphylaxis 

In some cases, food intolerances are mistaken for food allergies. Having a food intolerance (like lactose intolerance, for example) doesn't impact the immune system. That’s not to say they’re not frustrating or don’t cause discomfort, but unlike food allergies, they’re not potentially life-threatening.

Are food allergies permanent?

Some food allergies can be short-lived, while others last a lifetime. According to recent research, most children outgrow allergies or become tolerant of foods like eggs, milk, and wheat, but allergies to nuts and shellfish are typically more long-standing. Nearly 20% of children have a resolution of their food allergy by the time they’re old enough to go to school.¹¹

Custom skincare with Curology

If you think you’re experiencing food allergy symptoms like any we’ve mentioned here, it’s best to seek help from an in-person medical provider or dermatology provider to treat them. But if you’re concerned about other common skin conditions, like acne, anti-aging, hyperpigmentation, or rosacea, Curology’s here for you.

Getting started is easy. Answer a few questions and snap a few selfies to help us get to know your skin. If Curology is right for you, you’ll be paired with one of our in-house licensed dermatology providers. They’ll create a personalized prescription formula with ingredients to target your specific skin goals. Our full line of skin care products will complete your routine, designed by dermatology providers to be non-comedogenic, dye-free, paraben-free, and hypoallergenic.  

Sign up for Curology now! 

P.S. We did the homework so you don’t have to:

1. Gupta RS, Warren CM, Smith BM, et al. Prevalence and Severity of Food Allergies Among US Adults.JAMA Netw Open. (2019).  

2. Lopez CM, Yarrarapu SNS, Mendez MD. Food Allergies. StatPearls. (2022 September 26).

3. Foong RX, Santos AF. Biomarkers of diagnosis and resolution of food allergy. Pediatr Allergy Immunol. Ibid.

4. Edwards CW, Younus MA. Cow Milk Allergy. [Updated 2022 Jun 27]. In: StatPearls [Internet]. 

5. Mathew P, Pfleghaar JL. Egg Allergy. [Updated 2022 Jul 23]. In: StatPearls [Internet]. 

6. Patel R, Koterba AP. Peanut Allergy. [Updated 2022 Jul 5]. In: StatPearls [Internet]. 

7. Alonso LL, Armstrong L, Warrington SJ. Shellfish Allergy. [Updated 2022 Sep 26]. In: StatPearls [Internet]. 

8. Patel N, Samant H. Wheat Allergy. [Updated 2022 May 30]. In: StatPearls [Internet]. 

9. Geiselhart S, Hoffmann-Sommergruber K, Bublin M. Tree nut allergens. Mol Immunol. (2018).

10. Weinberger T, Sicherer S. Current perspectives on tree nut allergy: a review. J Asthma Allergy. (2018).

11. Lopez CM, Yarrarapu SNS, Mendez MD. Food Allergies. StatPearls. Ibid.

Disclaimer: Here at Curology, we don’t treat or diagnose food allergies—you’ll have to turn to your in-person medical provider for that. This article is meant for informational purposes and should not be taken as medical advice.

* Subject to consultation. Subscription is required. Results may vary. 

Written by

Curology Team

Medically reviewed by

Meredith Hartle, DO