Food allergy is an increasingly recognized manifestation of atopy. Patient and public awareness of food allergy is also increasing. Justifiable demands are being made for better medical guidance of the practice of food labelling for industry and catering businesses. Such advice must bear in mind the relative frequency and severity of allergies to certain foods. Some commonly allergenic foods (milk, egg, soya, wheat) are staple components of the diets of populations, used widely in prepared foods. The frequency of the allergies to these foods and their widespread uses means they and their derivatives must be declared on food labels. Less commonly used foods such as fish, shellfish, peanut, and tree nuts demand declaration due to the severity of reactions induced in the admittedly more rare, but increasingly common, sufferers of these allergies. Reactions to more unusual foods are increasingly being identified, and the "minimum" list is likely to be extended in the future.