Soybean oil allergyPrevalence for soy protein allergy is estimated at 0.5% in the general population and 3-6% in children. Refined soybean oil is normally not considered as an allergen because it contains low levels of soy protein, typically 0.15mg per kg. It is estimated that the average consumption of soybean oil results in the intake of only 0.01mg soy protein. Most of the soy protein in soybean oil are trypsin inhibitors and not the typical soy allergens.
EFSA opinion on soybean oil allergyOn November 27th, the European Union amended their food labeling directive by allowing the use of refined soybean oil in foods without having to declare the presence of soy allergens.
This EFSA study covers fully refined soybean oil, which is neutralized, bleached and deodorized soybean oil. It also covers derived products such as hydrogenated and interesterified soybean oil and fats. The researchers evaluated 2 clinical studies and concluded that is very unlikely that the consumption of fully refined soybean oil will trigger a severe allergic reaction in susceptible individuals.
In the first study the 30 individuals with peanut allergy, which have an increased risk of cross-reactivity with soybean protein, consumed increasing quantities of soybean oil or rapeseed oil (=control) up to a dose representing the highest intake for a single meal. Most participants experienced no symptoms. Only four participants showed mild reactions to soybean oil whereas six showed mild symptoms to the rapeseed oil. The same setup was used in the second study involving 32 participants with known soy allergy. Five participants showed mild reactions to the soybean oil and eight participants to the rapeseed oil.