A data-driven reduction of 39 human essential nutrients, 5 taste receptor families, and 15 deficiency diseases yields a non-redundant metabolic border structure: three acquisition borders, one exclusion border, one state sensor, and one internal cofactor layer. Taste receptors are identified as endogenous border-reading interfaces, the first CGS domain where the system reads its own borders. Cooking is a selective σ-operator: 8/8 published bioavailability comparisons match predicted direction. Properties P1–P4 verified. Defines the B-series (systems with internal border-reading).
davide lugli (Tue,) studied this question.