Vitamin C is a popular supplement. There are several forms of vitamin C available. Naturally you may wonder which vitamin C is best absorbed or has the best bioavailability? Bioavailability refers to the degree to which a nutrient becomes available to the target tissue after it has been administered. Does Vitamin C Type Affect Bioavailability? Vitamin C is also known as ascorbic acid, which is the form used in most supplements. However, there are other forms of vitamin C, including, sodium ascorbate (a mineral ascorbate), calcium ascorbate (a mineral ascorbate), other mineral ascorbates, ascorbic acid with bioflavonoids or combination products that blend different forms. Regardless of the form of vitamin C, their bioavailability is very similar. Although some singular studies show minor differences, the body of research surrounding vitamin C supplementation reflects that absorption remains high no matter which form you choose.