People allergic to what substance must avoid the food additive lecithin?

Lecithin is a food additive that can be derived from various sources, but the most common source is soybeans. Therefore, individuals who are allergic to soy must avoid lecithin, as consuming it could trigger an allergic reaction. Lecithin serves as an emulsifier in many food products, helping to blend ingredients that usually do not mix well, such as oil and water.

Those with soy allergies may experience a range of symptoms, from mild gastrointestinal distress to more severe reactions like anaphylaxis. It's crucial for those with this allergy to carefully read food labels, as lecithin is often included in processed foods, baked goods, chocolates, and many other products.

While individuals allergic to nuts, wheat, or milk must also be cautious and avoid those specific allergens, their allergies are not directly related to lecithin unless they are using a product where lecithin is derived from a source that is relevant to their allergies, which is less common. Thus, the primary concern for soy allergy sufferers is the presence of soy-derived lecithin in food items.