Shellfish in Canada: label rules and introduction guidance

Is shellfish on Canada's priority food allergen list?

Crustaceans and molluscs are a single priority allergen category in Canada, and Health Canada says they should be listed on prepackaged food using their common names, such as lobster, crab, clam or oyster. Its examples of molluscs include squid, octopus, scallops, mussels and snails; its crustaceans include crab, crayfish, lobster, prawns and shrimp. This is a key difference from the US, where molluscs are not a major food allergen. Health Canada also notes that people allergic to crustaceans may not be allergic to molluscs, and should ask an allergist.

Canada's priority food allergens are eggs, milk, mustard, peanuts, crustaceans and molluscs, fish, sesame seeds, soy, sulphites, tree nuts, and wheat and triticale. Under the enhanced labelling rules published in 2011, a prepackaged food must name each one by its common name in the list of ingredients or in a statement beginning with 'Contains'. Gluten sources (barley, oats, rye, triticale and wheat) are declared the same way. 'May contain' statements are voluntary, cannot be used when an allergen is added on purpose, and must follow the ingredients or 'Contains' statement.

• Canadian Food Inspection Agency: Food allergies and allergen labelling
• Health Canada: Common food allergens
• Health Canada: Crustaceans and molluscs, priority food allergens

What CPS guidance says about introducing shellfish

The CPS lists shellfish among the most common food allergens in children. Its practice point describes an evidence gap for early introduction of allergenic foods other than egg and peanut, so there is no shellfish-specific timing in it. The general guidance is to introduce allergenic foods one at a time without unnecessary delay, with an age-appropriate texture. If your baby has eczema or a parent or sibling with an allergic condition, the CPS considers them high risk and suggests common allergenic solids around 6 months; your paediatrician can advise on shellfish specifically.

In Canada, allergen introduction guidance comes from the Canadian Paediatric Society (CPS). Its practice point for infants at high risk (2019, updated 2020) defines high risk as a personal history of eczema or other atopy, or a parent or sibling with an allergic condition. For those babies it recommends considering common allergenic solids at around 6 months but not before 4 months, guided by developmental readiness; for babies at low or no risk, it recommends complementary foods at about 6 months.

• Canadian Paediatric Society: Timing of introduction of allergenic solids for infants at high risk

Logging shellfish in the app

The app's region picker has no Canada option yet. The US schedule covers all nine allergens in these guides, and Canadian priority allergens outside it, such as mustard, can be added as foods in the diary. In the schedule, shellfish appears as Shellfish. Each allergen entry moves from not started to introduced, cleared or reaction, and the 14-day window keeps new foods spaced out so a delayed reaction is easier to match to a food. Log prawn, crab or mussel by name, because crustaceans and molluscs are different allergen groups in most countries. If you see a symptom, log it with its severity; the paediatrician report gathers the dates into one PDF for your next appointment. It is a record for you and your doctor, not a diagnosis.