TOKYO -- Walnut and cashew allergies can be "treated" to a level that does not interfere with daily life, even though it is said that fewer than 10% of individuals with tree nut allergies naturally outgrow them, Japanese researchers confirmed.

The approach is designed to help people live comfortably without constantly worrying about nuts in everyday life. The National Center for Child Health and Development published the findings in the British allergy journal The Clinical & Experimental Allergy.

Walnuts and cashews carry a high risk of causing severe symptoms even if they are consumed in tiny amounts, and the standard approach has long been lifelong avoidance. However, trace amounts can still accidentally mix into meals and other foods, placing a heavy psychological burden on patients and their families.

The research team studied 27 children with walnut allergies and six children with cashew allergies between the ages of 4 and 18. Their goal was to "treat the allergies to the point where they would no longer cause problems in daily life."

The method uses a process in which the human body gradually stops recognizing the allergen as a harmful substance through regular exposure. The participants were given extremely small daily doses of protein from nuts, starting at just 0.45 milligrams per day. The amount was then carefully increased while professionals closely monitored for allergic reactions through oral food challenges.

As a result, over a long monitoring period of over 800 days, none of the participants developed moderate or severe symptoms, and none required emergency treatment for anaphylaxis or other allergy symptoms. After about 3 1/2 years of treatment, all 33 participants were able to consume up to 750 milligrams of nut protein, equal to about 5 grams of actual nuts, without problems.

Blood test results also showed a reduction in substances in the body that trigger allergic reactions, with decreases seen in 57% of walnut allergy cases and 58% of cashew allergy cases.

The research team commented, "If patients can tolerate up to 750 milligrams (of protein in nuts), it may help prevent accidents related to processed foods, eating out, or trace contamination. The idea that nut allergies can't be overcome is becoming a thing of the past."

However, the researchers warned that individuals should not attempt this procedure on their own. The team added, "We hope to establish a method that can be carried out safely at many medical institutions."

(Japanese original by Ryo Watanabe, Lifestyle, Science & Environment News Department)