People who are diagnosed with food allergies need to avoid eating the foods that trigger their symptoms. However, simply avoiding those allergenic foods often isn’t enough to eliminate symptoms—that’s where cross-contamination comes in.
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Cross-contamination occurs when a food allergen contaminates a food that is naturally free of allergens. For example, during food preparation in the kitchen, bread crumbs from a regular slice of toast may be left behind in a toaster. These leftover crumbs in the toaster may then contaminate a wheat-free slice of toast, causing an allergic reaction for someone withceliac diseaseor non-celiacgluten sensitivity.
This problem also can occur in manufacturing facilities. For example, food products made with tree nuts can contaminate the processing of other foods made on the same manufacturing line. For this reason, products are required to include a warning if their facility also manufactures foods that include one of the top food allergens on the same processing equipment.
Cross-contamination can occur almost anywhere, at home, in restaurants, at school or on manufacturing lines.
Cross-contamination can happen during food preparation, cooking, storage, or even when serving. All it may take is gluten-free pasta cooked in the same pot that was used for regular pasta, eating a salad after a piece of cheese is removed from the top or a knife not properly cleaned from the peanut butter jar. For a person with food allergies, these situations can lead to life-threatening reactions.To help safeguard your food, follow these guidelines to reduce the risk of an allergic reaction.
Cross-Contamination in Packaged Foods
Food manufacturers often use the same facilities or equipment to process and package products that contain allergens. To safeguard yourself:
Cross-Contamination in the Home
In most households where family members with food allergies have a high risk ofanaphylaxis, family members avoid bringing foods with those allergens into the house. This is the safest way to avoid cross-contamination. If the house is clear of these foods, all family members can live in a safer, allergy-free environment.
If you do however keep foods with these allergens in the home, follow these rules:
Cross-Contamination in Restaurants
Whenchoosing a restaurant, it is important to determine if the restaurant’s staff members are familiar with food allergies and have an established protocol for food safety. Speak to a manager before ordering to make sure the staff understands your food allergy-related needs.
Still, despite a restaurant’s best efforts, cross-contamination can still occur if all safe practices are not upheld. The most common causes of cross-contamination in restaurants are often related to the frying oil, griddles or grills, and woks.The actual cooking of food poses more risk in a restaurant than in typical prep areas, as those areas are usually more closely monitored and understood.
When dining out:
A Word From Verywell
There are several other common ways that cross-contamination can occur, and you should be aware of them.
For example, knives, cutting boards, counter surfaces, and spoons are at high risk for cross-contamination, since they’re often used repeatedly with different types of foods. Make sure they’re washed thoroughly with hot soapy water. Plastic cutting boards provide a safer option as they are easier to clean and sanitize than wooden boards as they can also be cleaned in the dishwasher.
Be particularly careful about nuts and seeds, as they may leave an oily residue, potentially leaving allergens behind on plates, counters, tables and cutting boards. Clean with a household cleaning agent thoroughly to prevent cross-contamination.
Refrain from sharing cups or eating utensils with others, as they can easily be contaminated with allergens. For some people, all it takes is a simple touch of the hand, face or lips to evoke an allergic reaction.
Bagel or meat slicers, if not cleaned thoroughly, may be contaminated with food allergens. Be sure to advise at the deli counter that you have a food allergy and ask for them to change their gloves and to clean the machines before slicing.
Bulk food bins may also be a source of cross-contamination as the sharing of scoops between items can potentially transfer allergens. Always ask the store manager if cross-contamination precautions have been taken.
In any case, if you believe there’s a risk of cross-contamination either at home or in another setting, choose a different food or don’t eat.
6 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Beyond Celiac Research Foundation.Cross-Contact.U.S. Food and Drug Administration.Food allergies.Food Allergy Research and Education Foundation.Prevent Cross-Contact.Food Allergy Canada.Avoiding Cross-Contamination.World Health Organization, Food and Agriculture Organization of the United Nations.CODE OF PRACTICE ON FOOD ALLERGEN MANAGEMENT FOR FOOD BUSINESS OPERATORS.Asthma and Allergy Foundation of America.Is it Safe for Me to Eat Foods Fried in the Same Oil as my Allergens.
6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Beyond Celiac Research Foundation.Cross-Contact.U.S. Food and Drug Administration.Food allergies.Food Allergy Research and Education Foundation.Prevent Cross-Contact.Food Allergy Canada.Avoiding Cross-Contamination.World Health Organization, Food and Agriculture Organization of the United Nations.CODE OF PRACTICE ON FOOD ALLERGEN MANAGEMENT FOR FOOD BUSINESS OPERATORS.Asthma and Allergy Foundation of America.Is it Safe for Me to Eat Foods Fried in the Same Oil as my Allergens.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Beyond Celiac Research Foundation.Cross-Contact.U.S. Food and Drug Administration.Food allergies.Food Allergy Research and Education Foundation.Prevent Cross-Contact.Food Allergy Canada.Avoiding Cross-Contamination.World Health Organization, Food and Agriculture Organization of the United Nations.CODE OF PRACTICE ON FOOD ALLERGEN MANAGEMENT FOR FOOD BUSINESS OPERATORS.Asthma and Allergy Foundation of America.Is it Safe for Me to Eat Foods Fried in the Same Oil as my Allergens.
Beyond Celiac Research Foundation.Cross-Contact.
U.S. Food and Drug Administration.Food allergies.
Food Allergy Research and Education Foundation.Prevent Cross-Contact.
Food Allergy Canada.Avoiding Cross-Contamination.
World Health Organization, Food and Agriculture Organization of the United Nations.CODE OF PRACTICE ON FOOD ALLERGEN MANAGEMENT FOR FOOD BUSINESS OPERATORS.
Asthma and Allergy Foundation of America.Is it Safe for Me to Eat Foods Fried in the Same Oil as my Allergens.
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