Artificial food colorants can cause disease when the immune system has become dysregulated, Icahn School of Medicine at Mount Sinai researchers report.
The study, published in Cell Metabolism in May, was the first to show this phenomenon.
The study, conducted in mice, found that the mice developed colitis when they consumed food with the artificial food colorants FD&C Red 40 and Yellow 6 when a specific component of their immune system, known as cytokine IL-23, was dysregulated.
While it remains unclear whether food colorants have similar effects in humans, researchers plan to investigate exactly how cytokine IL-23 promotes the development of colitis after food colorant exposure.
Colitis is a form of inflammatory bowel disease (IBD), and cytokine IL-23 dysregulation is known to be a factor in the development of IBD in humans. Medicines that block its function are now successfully used in patients. Food colorants such as Red 40 and Yellow 6 are widely used in food, drink, and medicine. These two food colorants are the most commonly used in the world.
Both genetic predisposition and environmental factors appear to play a role in whether a person develops IBD, a condition that affects millions of people worldwide, but the exact environmental factors have remained elusive.
For the study, the researchers created mouse models that had a dysregulated expression of cytokine IL-23. To their surprise, the mice with the dysregulated immune response did not develop inflammatory bowel disease spontaneously even though dysregulated IL-23 is a factor in people with the disease.
When given a diet with the food dyes Red 40 or Yellow 6, the altered mice developed colitis. However, mice that had the dye-infused diet but had a normal immune system did not develop IBD.
To prove that the food colorant was indeed responsible, the researchers fed the altered mice diets without the food colorant and water containing it; in both cases, the disease developed when the mice consumed the colorant, but not otherwise. They repeated this finding for several diets and several food colorants.
“The dramatic changes in the concentration of air and water pollutants and the increased use of processed foods and food additives in the human diet in the last century correlate with an increase in the incidence of inflammatory and autoimmune diseases,” said senior author Sergio Lira, MD, PhD, the Leona M. and Harry B. Helmsley Charitable Trust Professor of Immunology at the Precision Immunology Institute at Icahn Mount Sinai.
“These environmental changes are thought to contribute to development of these diseases, but relatively little is known about how they do so. We hope this research is a step toward understanding the impact of food colorants on human health.”
Tartrazine and erythrosine are two synthetic azo dye primarily adopted as food colorant to improve the quality of food products. These dyes are certified as colorants by FDA for its food, drug and cosmetic use but it is also generally used in other chemical industries. Toxicological studies have shown that high dose consumption of these colorants is toxic in rats and mice (Abd-Elhakim et al., 2018; Marwa et al., 2019).
Synthetic food dyes or colorants include pigments occurring naturally. Given their properties and availability such as it low cost, stability and it colorful attraction, large quantities are produced yearly. However, high stringent guidelines are been placed on the use and consumption of dye whereby the safety limit used in food and other industrial products is still under continuous debate till today.
There are significant concerns regarding the effect of food colorants on human health, most especially in children in which hyperactivity have been reported (Neeta, 2018). Other reports have shown behavioral impairment, psychological deficit and biochemical alterations in organs of laboratory rodents when exposed to artificial food additives or colorants in experimental based study (Albasher et al., 2020).
Additionally, continuous exposure to food colorants in experimental rodents reveals reproductive alterations and teratogenicity in newborns, testicular damage, cardiomegaly, kidney and liver damage, immune alteration, gastrointestinal toxicity and also toxic to the hematopoietic system (Boussada et al., 2017; Abd-Elhakim et al., 2018; Neeta, 2018; Marwa et al., 2019).
Emerging evidence shows that severe exposure to colorants may become neuro-invasive capable of inciting neurodegeneration and or disorders related to neuropsychiatric disease produced through increased biomarkers of oxidative and neuroinflammatory stress (Albasher et al., 2020). T
hese evidences have led to experimental models using animals exposed to colorants to mimic several features of different neurodegenerative disease (Albasher et al., 2020).
Moreover, neuronal inflammation and oxidative stress has individual features associated with neurobehavioral deficit observed in neurodegenerative disease conditions. Activating the body’s immune system in response to neurotoxicity, the food colorants led to a profound change in behavior and physiology of the nervous system (Doguc et al., 2019). Therefore, the over-administration of food colorants or dyes could promote the generation and release of inflammatory biomarkers (Doguc et al., 2019).
Although, there seem to be paucity of investigation on the adverse effect of food colorants or dyes on the cholinergic neurotransmission system and pro-inflammatory cytokine infiltration in both clinical and pre-clinical study. Therefore, the aim of this study was to investigate the adverse effect of combine erythrosine and tartrazine on cognitive and neurobehavioral functions, endogenous antioxidants, cholinergic system and pro-inflammatory cytokines in rats.
reference link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7970276/
Funding: The study was funded by grants from the National Institutes of Health. This research was also led by Zhengxiang He, PhD, Instructor of Medicine and Clinical Immunology, and Lili Chen, PhD, Assistant Professor of Medicine and Clinical Immunology, at Icahn Mount Sinai.
Source: Mount Sinai Hospital