The allergies are becoming more common as nuts are used as "hidden" ingredients in a growing range of everyday foods. Allergy specialists are calling for detailed product labelling of all foods known to contain even minute amounts of peanuts or nuts.
The findings also highlight the danger of giving peanut butter to babies. More than a third of the nut allergy cases reported occurred in children under two, most of whom were given the spread in the first 12 months of life.
But doctors say milk from mothers who eat peanuts also poses a greater risk of the child developing an allergy, and call for more research into baby milks and infant foods which contain peanut oils to determine if they can trigger an allergy.
Allergy specialists say that avoidance of peanuts/nuts by young children is the only safeguard, particularly by those with other allergies such as hayfever, asthma, and eczema who are at greater risk.
However, they warn that avoidance is difficult to achieve as nuts are a "hidden" ingredient in many foods, including cereals, chilli and spaghetti sauces, gravy mixes, oriental dishes, pastries, sweets and ice-creams.
Deaths in healthy young people from peanut/nut allergy are rare but becoming more frequent. Six patients died of peanut allergy in 1993.
In one of the most detailed investigations of peanut/nut allergies to date, Dr Pamela Ewan from Addenbrooke's Hospital NHS Trust in Cambridge, studied 62 cases of peanut/nut allergy in patients at the Allergy Clinic over one year.
According to a report in tomorrow's British Medical Journal, 23 patients were aged between 11 months and five years, and 52 in all were under the age of 18. The 10 adults were aged between 19-32.
Dr Ewan found that peanuts were the most common cause of allergy (47), followed by Brazil nut (18), almond (14), and hazelnut (13). (Some patients showed multiple nut allergies.) Peanuts accounted for all allergies in children sensitised in the first year of life and for 82 per cent of allergies in children by the third year of life. The most common symptom of allergy was swelling of the airways, face, and lining of the mouth, and in fatal cases, asphyxia was the cause due to swelling in the throat.
Peanuts are the leading cause of food allergy in the United States and, together with other nuts, are probably the leading cause of fatal and near fatal shock (anaphylaxis) reactions induced by food.
Peanuts are more popular there than in the UK, and the average American consumes 11lb a year. But the growing range of peanut products, and peanuts as an ingredient in convenience and junk foods, is believed to be behind the surge in cases there.Reuse content