Today, there is an evident need to keep reinforcing the safety of foods with sound scientific evidence. To this end, the food additive carrageenan (CGN) is at the heart of considerable debate and we have been interrogating its antinutritional effect on digestive proteolysis in toddlers, adults and seniors. Various physicochemical characterizations, proteomic analyses and multivariate analyses establish electrostatic biopolymer interactions as the strongest determinants of the digestive fate of food-proteins and bioaccessibility of bioactive peptides. Altogether, this work highlights a need to better understand the possible adverse effects and chronic toxicity of CGN consumption which is on the rise in the western diet, particularly amongst toddlers and children.