Will Novel Foods Cause Allergies?

For these reasons we look for patterns in foods that are known to be allergenic and whether or not these patterns are present in a newly introduced food. Because it’s proteins within foods that are responsible for food allergy, we are particularly interested in the proteins that are present in novel foods. Both Canada and the European Union have distinct novel food regulations that require manufacturers to examine the potential allergenicity of novel foods under intended use. Currently, the U.S. does not have a separate set of regulations for novel foods, but the questions raised are broadly similar:

How is the novel food related to known allergenic foods and commonly consumed non-allergenic foods? Organisms that are closely related to each other generally contain similar amounts of similar (by amino acid sequence) proteins. It follows that a protein type that’s an allergen in one food may also be an allergen in another food. There are numerous examples of types of proteins that are allergens in more than one type of food. Such proteins are often referred to as “pan-allergens” and include lipid transfer proteins in fruits and cereal crops, and tropomyosins in fish and shellfish. If a novel food contains a protein that’s similar to known allergenic food, this suggests the novel food may be allergenic. We can readily examine the similarity of proteins if their amino acid sequences are known. For this reason, databases of known allergenic proteins (such as www.allergenonline.org) are important when assessing allergenic risk from a new food. Proteins of similar sequence to known allergens may be further tested in the laboratory to examine the risk of cross-reactivity.

How much protein from the novel food is likely to be consumed? The higher the dose of protein consumed, the more likely it is that individuals may become sensitized or undergo an allergic reaction. The dose of protein delivered to consumers depends on how much protein is in the novel food, and how much of the novel food is likely to be consumed. For this reason, some novel protein isolates of foods that are already commonly consumed (e.g., pea protein) may pose allergen risks that weren’t previously noticed by the consumer, if they’re concentrated and consumed in a large quantity. A protein-rich novel food that’s intended to be consumed in large quantity (e.g., a meat replacer or protein-rich drink) is likely of greater concern than low-protein, low-consumption foods (e.g., an oil-based condiment).

Are the proteins in the novel food easily digested? It has long been known that proteins that are not easily digested in the human stomach, or possibly in the intestinal tract, are more likely to be allergens. Given that parts of a protein must survive for the immune system to recognize and react to it, this hypothesis is reasonable. It should be noted, however, that many poorly digested food proteins are not allergens. We can examine how digestible proteins from novel foods are in the laboratory using protein-digesting enzymes from mammals. Novel foods that contain proteins that do not break down with enzyme treatment, or that only partially break down, would be considered candidates for becoming an allergen, especially if they’re abundant in food.

Novel Foods Challenges

Novel foods are very different from one another with respect to potential allergen risk. Currently, our understanding of food allergy allows us to identify novel foods that may present a particularly high risk, but little more. Assessing the ability of a novel food to sensitize consumers is a particular problem. Ultimately, it’s regulatory agencies that decide on the safety of novel foods. Pathways to the regulatory acceptance of novel foods should be clear, rely on the best and most relevant scientific evidence, and not introduce unnecessary burden to the food manufacturer.