two good review articles on the harms of food dyes 1. https://pubmed.ncbi.nlm.nih.gov/23026007/ 2. https://www.sciencedirect.com/science/article/abs/pii/S09… Children are considered especially vulnerable due to their lower body weight (they get a greater weight based dose in a day) Production of Red 40, Yellow 5, and Yellow 6 leaves behind contamination with benzidine and other carcinogens. Dyes have been associated with a colitis, renal insufficiency, hepatotoxicity, pathological changes in the gut, and oxidative stress.