Popular E-supplement causes intestinal inflammation
Allura Red AC (also known as FD&C Red 40 or E129) was found to cause colitis in mice. The study was published in the journal Nature Communications.A common red food coloring causes intestinal inflammation in mice, according to a new study by McMaster University staff. Scientists suggest that regular consumption of the substance increases human susceptibility to inflammatory bowel diseases such as Crohn's disease and colitis.
The authors of the new study examined food colorings known as azo dyes. These are azo compounds characterized by the obligatory presence of one or more -N=N- azo groups in their composition. Although most azo dyes are considered safe and non-toxic, several previous studies have shown that some of them exhibit pro-inflammatory properties in animals. Therefore, experts examined the potential of azo dyes to contribute to inflammatory bowel disease (IBD).
Inflammatory bowel disease (IBD) is a group of pathologies characterized by chronic, long-term inflammation with associated symptoms. Currently, it includes two diseases: Crohn's disease and nonspecific ulcerative colitis (NUC).
The main hypothesis of the researchers is that azo dyes promote the secretion of serotonin in the intestine. This hormone aggravates the development of intestinal inflammation. After screening the researchers selected four popular azo dyes used as food colorings: Allura Red AC (also known as FD&C Red 40 or E129), Brilliant Blue FCF, Sunset Yellow FCF and Tartrazine Yellow. Of these, Allura Red has the most pronounced effect on serotonin secretion, which prompted the researchers to focus on it in further animal tests.
In the experiment, mice were given either a normal diet or a diet supplemented with Allura Red (AR) for 12 weeks. After this period, the mice exposed to AR chronically developed mild colitis. At the same time, serotonin levels in the intestine increased. However, intermittent AR exposure did not cause the mice to develop colitis. Only constant daily intake of the dye for several weeks caused intestinal inflammation.
The experiment also showed that the food supplement only caused inflammation in subjects with a predisposition to the condition. It could be due to genetic factors or a certain lifestyle.