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In the restaurant industry, the No. 1 star of your business is the food. The ingredients you choose, the meals you deliver and the experience they create all work together to drive your restaurant business to success. But what do you do when you have customers with specific food allergies?

According to the U.S. Food and Drug Administration, millions of people across the U.S. have food allergies — and you want to be able to meet their dietary needs in your restaurant. There’s no cure for food allergies, so it’s important for restaurants to do what they can to prevent triggering a food allergy. Although most reactions cause mild symptoms, there are many that can be life-threatening.

No restaurant owner wants a patron of their business to suffer an allergy attack. To open your doors to all customers and their allergies, you must clearly identify what common food allergens exist in your menu, outline how to prevent cross-contamination and then determine how to share that information with your patrons.

What is a food allergen?

The body’s immune system is supposed to identify and destroy harmful germs as a self-defense mechanism. However, a food allergen is a food that the immune system mistakenly identifies as harmful.

Due to this overreaction to a safe food item, the immune system releases chemicals, such as histamine, to cause inflammation. Exposure to even a very small amount of the food allergen can trigger a reaction. For some, this reaction may be minor and mildly uncomfortable, but for others, it can cause life-threatening reactions.

Food allergies can develop over time or be identified at a young age. Family history does increase the chances of developing a food allergy.

Food allergy vs. intolerance

It’s important not to confuse a food allergy with food intolerance. Although they can share similar physical symptoms, they’re not interchangeable.

A food allergy triggers the immune system into an abnormal protective mode, creating mild to serious reactions. Meanwhile, food intolerance mostly only affects the digestive system.

Additionally, those with food intolerance may sometimes be able to eat small amounts of the food that trigger their symptoms. There are also treatments for food intolerance to help digest the offending food. A common example of this is to take lactase enzyme pills (Lactaid) if you’re intolerant to lactose.

Celiac disease is not a food allergy or food intolerance.

How to recognize food allergy symptoms

If a customer at your restaurant accidentally comes in contact with one of their food allergens, it’s important to recognize the signs earlier so you can contact medical professionals for help.

For some people with allergies, a reaction may only be mildly uncomfortable, but for others, it can trigger frightening symptoms. Symptoms typically develop within a few minutes to two hours after consuming a food allergen. In rare cases, they may occur several hours after.

According to the Mayo Clinic, common food allergy symptoms include:

  • Tingling in the mouth
  • Swelling of a part of the body (e.g., mouth, face, throat, etc.)
  • Hives or eczema
  • Congestion or trouble breathing
  • Abdominal pain
  • Vomiting
  • Nausea
  • Anaphylaxis

It’s vital to seek medical help the moment someone shows signs of anaphylaxis, which is a severe allergic reaction. Important signs to spot anaphylaxis include:

  • Swelling in the throat
  • Constricted airways
  • Rapid pulse
  • Anaphylactic shock (extreme lowering of blood pressure)
  • Dizziness
  • Loss of consciousness

Top 8 most common food allergens

Per the U.S. Food and Drug Administration, these are the top 8 most common food allergens:

1. Milk

One of the top food allergens in the U.S. is cow’s milk. It mostly affects babies and toddlers, making it one of the most common childhood allergies.

The good news is that it’s not a very common allergy for adults — most children outgrow their allergy to cow’s milk by the time they turn three years old.

If someone with an allergy to milk comes into contact with the allergen, they’ll usually start showing reactions within five to 30 minutes. This type of allergy is often confused with the common food intolerance to lactose.

2. Eggs

This is another allergen that mainly affects children. Thankfully, many children outgrow this allergy by the time they turn 16 years old. 

Some people are allergic to egg whites, but not yolks, while for others it’s the reverse. This is due to the different proteins that exist in the egg whites versus the egg yolks. Most people are mainly allergic to egg whites. In either case, the best treatment may be to opt for an egg-free diet.

Interestingly, there are people with this allergy who can eat fully cooked eggs because the heat changes the shape of the allergy-causing proteins. This prevents the immune system from recognizing the allergen and triggering a reaction.

3. Fish

Most people who have a fish allergy are allergic to more than one type of fish. This can include bass, flounder, cod, etc. This allergy can develop either in childhood or as an adult and can cause severe allergic reactions. A fish allergy is easy to confuse with a reaction to contaminated fish due to similar symptoms.

Be careful not to confuse a fish allergy with a shellfish allergy. Fish with fins and shellfish carry different proteins, which means people who are allergic to fish may be able to eat shellfish with no problem.

4. Crustacean shellfish

You may already be familiar with shellfish allergies as they’re one of the most common allergies showcased in pop culture media. This allergen triggers the immune system due to proteins found in crustacean and mollusk families of fish.

Common shellfish allergens include:

  • Shrimp
  • Prawns
  • Lobster
  • Scallops

Similar to a fish allergic reaction, a shellfish allergy can often be confused with symptoms of eating contaminated food (e.g. vomiting, diarrhea and abdominal pain). A shellfish-caused allergic reaction will typically occur pretty quickly after someone has consumed the offending crustacean. 

An important fact for restaurant staff to understand about this allergen is that even the vapors from cooking shellfish can trigger someone’s allergic reaction. This is why those with this allergy should steer clear of kitchens that are cooking seafood.

5. Tree nuts

Tree nuts are a very common food allergen. As the name suggests, tree nuts are the nuts and seeds that are created by trees.

Tree nuts include:

  • Walnuts
  • Pecans
  • Almonds
  • Cashews
  • Macadamia nuts
  • Pistachios
  • Walnuts
  • Pine nuts
  • Brazil nuts

If someone is allergic to one type of tree nut, it’s recommended that they avoid all tree nuts as a precaution. Many peanut-free alternatives contain tree nuts, and those products should be avoided — unless they state they don’t contain tree nuts, of course.

Those allergic to tree nuts aren’t automatically allergic to peanut butter.

If you have a tree nut allergy, you’ve probably been advised to carry an EpiPen, which is an epinephrine auto-injector, in the case of a severe allergic reaction. Epinephrine is also known as adrenaline and it can help reverse the effects of life-threatening reactions.

6. Peanuts

Like shellfish allergies, most people are well aware of the dangers of a peanut allergy. Extremely common with often severe allergic reactions, those who are allergic to peanuts are advised to completely avoid them.

Peanuts are legumes, which is why they are a different allergen than tree nuts. It’s possible to grow out of a peanut allergy over time.

7. Wheat

Wheat allergies mostly affect children and can often be outgrown by the age of 10. Due to similar symptoms with celiac disease and non-celiac gluten sensitivity (e.g., digestive issues, hives and vomiting), wheat allergies can sometimes be more difficult to identify.

However, celiac disease and non-celiac gluten sensitivity are caused specifically by gluten. In contrast, a wheat allergy can stem from any of the proteins found in wheat, not just gluten.

8. Soybeans

A soy allergy is mostly found in infants and children under three. The good news is that most children eventually outgrow the allergy and are able to consume soy and soy-based products as adults.

Common symptoms of a soybean-related allergy attack include an itchy mouth, runny nose and breathing difficulties. Soy is a very common ingredient in food, including soy milk and soy sauce.

Restaurant protocol for food allergens

Living with a food allergy doesn’t mean you don’t go to restaurants. Due to this, it’s important for restaurants to take protective measures to ensure the safety of diners. We’ve outlined best practices for serving customers with food allergies, but there’s more that you can do to make your restaurant allergy-friendly.

Besides contamination prevention, restaurant operators can optimize their current menu (both physical and digital copies). Below are some helpful tips:

  • Include ingredients lists for menu items. Have ingredients lists on hand that can clarify exactly what goes into each dish, so the customer can be certain they don’t come into contact with their food allergen(s).
  • Highlight when dishes contain common food allergens. Cross-check your menu with the top 8 most common food allergens and include a note for those dishes.
  • Offer food substitutions. If you can make the same meal gluten-free or milk-free, let them know on the menu. Your customer will appreciate the extra option.

In addition to improving your restaurant menu, it’s also essential to train front-of-house (FOH) staff on how to serve customers with food allergies and what to do in the case of an allergic reaction. These procedures help create a welcoming environment and could potentially save a life.

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