Vitamin C also added to some fruit juices and juice drinks. Tablet and capsule content ranges from 25 mg to 1500 mg per serving. The most commonly used supplement compounds are ascorbic acid, sodium ascorbate and calcium ascorbate. Vitamin C molecules can also be bound to the fatty acid palmitate, creating ascorbyl palmitate, or else incorporated into liposomes. In 2014, the Canadian Food Inspection Agency evaluated the effect of fortification of foods with ascorbate in the guidance document, "Foods to Which Vitamins, Mineral Nutrients and Amino Acids May or Must be Added". Voluntary and mandatory fortification was described for various classes of
Vitamin B12 leading to vitamin B deficiency. Protein-bound vitamin B must be released from the proteins by the action of digestive proteases in both the stomach and small intestine. Gastric acid releases the vitamin from food particles; therefore antacid and acid-blocking medications (especially proton-pump inhibitors) may inhibit absorption of B. B taken in a low-solubility, non-chewable supplement pill form may bypass the mouth and stomach and not mix with gastric acids, but acids are not necessary for the absorption of free B not bound to protein; acid is necessary only to recover naturally-occurring vitamin B from foods. R-protein (also known as haptocorrin