Calcium Ascorbate
Calcium Ascorbate is a tier 2 form of Vitamin C, used in 1,208 on-market products .
1,208
on-market products
tier 2
quality tier
n/a
elemental fraction
Why this tier: Not shown more bioavailable than plain ascorbic acid in the cited comparison (result not independently confirmed); it delivers less vitamin C per mg of ingredient mass (about 83-90% ascorbic acid by mass for the dihydrate/anhydrous salt) due to the bound mineral. A reduced GI/acid-irritation advantage is commonly claimed but is unsourced here.
Source: Johnston CS, Luo B. 1994, PMID 8021423