Drink less colored drinks, studies have found that two common food dyes may induce or aggravate colitis!

Intestinal damage, such as physical stimulation, insufficient blood supply to organs, microbial infection, and toxin exposure, can cause enteritis. Statistics from the World Health Organization (WHO) show that there are 120 million gastrointestinal disease patients among the 1.4 billion Chinese people. Among them, chronic enteritis ranks first with a proportion of 38%. Intestinal inflammation is not easy to cure, and repeated attacks will cause the symptoms to become more serious and eventually lead to cancer.

People who have long consumed high-fat, low-fiber processed meat products are at high risk. In addition, long-term consumption of processed foods and food additives is also associated with an increase in enteritis.

Recently, a study published in the journal Cell Metabolism found that two commonly used edible pigments, Allura Red and Sunset Yellow, can actually induce colitis in mice overexpressing IL-23! The mechanism behind this is related to IFN-γ, CD4 T cells, and two specific intestinal microorganisms.

The professional name of Allura Red is Red 40, and it also has another name called Allura Red. This pigment is one of the most widely used food pigments in the world. Almost all colored drinks and snacks you have ever seen have this name in the ingredient list.

Researchers at the Icahn School of Medicine at Mount Sinai in the United States found that giving mice allura red alone or overexpressing an immune factor, interleukin-23 (IL-23), alone did not induce colitis, but when these two appeared together, the mice immediately developed severe enteritis, as shown by obvious leukocyte infiltration, crypt loss, epithelial damage and ulcers in both the cecum and colon. IL-23 is one of the factors that promote the development of colitis.

The researchers also specifically tested two human foods containing allura red, and both drinks could induce similar effects. In this process, IFN-γ expressed by CD4 T cells driven by IL-23 was the key. With allura red IL-23, significant colitis could be observed on day 56.

Subsequent studies have found that intestinal microbes also play a role in this. Germ-free mice do not experience the phenomenon of IL-23 allure red = colitis, which means that the intestinal flora does play a role in this. After investigation, it was found that two types of intestinal bacteria are the key to allure red's "mischief", they are Bacteroides ovatus and Enterococcus faecalis.

Under the action of these intestinal bacteria, 1-amino-2-naphthol-6-sulfonic acid sodium salt (ANSA-Na) produced after metabolism of allura red directly causes inflammation.

Can other pigments also cause enteritis?

The same was true for another food coloring, Yellow 6, also known as sunset yellow. However, non-azo colorings, such as erythrosine (Red 3) and brilliant blue (Blue 1), did not cause colitis in IL-23 overexpressing mice.

Although many food experts believe that these food additives are safe, at least in animal studies, they did not know about intestinal microorganisms before, and the impact on intestinal microorganisms was not used as an evaluation indicator. Now that we know the existence of intestinal microorganisms, this indicator must be added to the safety assessment of food additives in the future. But before that, it is better to avoid drinking colored drinks as much as possible.

You are encouraged to eat a healthy diet, increase the intake of crude fiber and fresh fruits, avoid high-fat and high-protein diets, limit processed foods, quit smoking, quit drinking, etc. to prevent long-term toxicity and irritation to the digestive tract. . . . .

Can you do it?

Food colorants metabolized by commensal bacteria promote colitis in mice with dysregulated expression of interleukin-23

2021DOI:doi.org/10.1016/j.cmet.2021.04.015