A small study involving laboratory mice suggests that frequent and long-term exposure to the dye (also called FD&C Red 40 and Food Red 17) harms gut health and promotes inflammation. Recently published in Nature Communications, the research found that the additive directly disrupts the gut barrier (which helps prevent bacterial intrusion) and increases the production of serotonin, a hormone and neurotransmitter found in the gut. This reaction changes the gut microbiome, leading to increased susceptibility to inflammatory bowel conditions, according to the report. “What we have found is striking and alarming, as this common synthetic food dye is a possible dietary trigger for IBDs,” said the study’s senior author Waliul Khan, PhD, who researches gastrointestinal inflammation at McMaster University in Hamilton, Ontario. “This research is a significant advance in alerting the public on the potential harms of food dyes that we consume daily,” added Dr. Khan in a press release. For the 12-week experiment, six mice were fed a daily control diet without the dye, while six mice were given a similar diet with the dye. Khan and his collaborators observed a link between exposure to the red coloring and disturbances in the gut microbiome, which caused mild intestinal inflammation. Furthermore, mice exposed early in life were found to have a “heightened susceptibility” to colitis or inflammation of the large intestine. In a separate experiment, researchers intermittently exposed six mice to Red 40 via diet for just one day per week for 12 weeks. The study authors noted that intermittent consumption of the dye was “more akin to a typical human exposure” and did not influence susceptibility to intestinal inflammation.
FD&C Red 40 Food Dye Has Long Been a Suspected Health Hazard
This latest study contributes to a growing body of evidence suggesting that Red 40 could be harmful to health. As far back as the 1970s, health officials were warning that the ingredient could be a public health hazard, according to The New York Times. One of the most common concerns surrounding artificial food dyes is its behavioral effect on children. According to the American Academy of Pediatrics, eliminating artificial food dyes from the diets of children with attention deficit hyperactivity disorder can help decrease their symptoms. Major public health groups have concluded that the amount of the chemical dye in the average diet is too low to pose a threat. The World Health Organization writes, “dietary exposure to Allura Red AC for children and all other age groups does not present a health concern.” The U.S. Food and Drug Administration has also approved Allura Red AC for human consumption. The recommended daily intake should not exceed 3.2 milligrams per pound of a person’s body weight. For a person weighing about 130 pounds, a 32-ounce bottle of fruit punch Gatorade would be about 10 percent of that daily limit, according to the Centers for Disease Control and Prevention (PDF). The red dye is ubiquitous in processed foods. Food manufacturers use it in candies, snacks, soda, soft drinks, and cereals, as well as in condiments, ice creams, baked goods, fruit juices, and cosmetics.
What Causes Inflammatory Bowel Disease?
Khan stressed that the exact causes of IBD are still not fully understood, but several factors may be involved, including gut microbiota imbalances, immune system disruptions, and environmental elements. Environmental triggers of IBD include the typical Western diet, which includes processed fats, red and processed meats, sugar, and a lack of fiber, according to Khan. He added that the Western diet and processed foods also include large amounts of various additives and dyes. Based on this study’s results, Khan suggested that the link between commonly used food dyes and IBD warrants further exploration.
