Dietary management of histamine intolerance

Histamine intolerance is defined as a non-toxic adverse reaction caused by a reduced capacity of the human body to degrade dietary histamine at intestinal level. Although some symptoms can be confusing, it is not an allergy, since it lacks immunological mediation, nor it is food intoxication, because it can occur after the consumption of foods with normal or even low amounts of histamine. The most studied cause of histamine intolerance is a deficit in the intestinal enzyme activity Di-Amino-Oxidase (DAO). DAO deficiency may have a genetic origin, since polymorphisms have been linked with low activity, or it may be secondary to inflammatory bowel diseases, or by a temporary inhibition derived from certain drugs. Recently, it was proposed that there may be a relationship between intestinal dysbiosis and histamine intolerance. Currently, the most recommended strategy to prevent the appearance of symptoms of this intolerance is the follow-up a lowhistamine diet, based on the exclusion of those foods that patients associate with symptomatology. Among the foods that are excluded are those in which a high presence of histamine can be expected, but also some foods that, a priori, do not contain histamine. According to data from our research group, some of these foods may contain high levels of other diamines, which due to enzymatic competition for DAO would enhance the absorption of histamine and would explain the appearance of its adverse effects. In 2017, the European Commission approved the commercialization of an enzyme supplement formulated with DAO from porcine kidney protein extract as a novel food, which would improve the degradation of histamine at the intestinal level, allowing a less restrictive diet to be followed. Currently, work is underway to obtain new sources of DAO from plant sources and in the form of probiotics. In the framework of the congress, the main results of our research group that add scientific evidence to this new intolerance, especially regarding its dietary management, will be exposed.