Ester C, commercial name for calcium ascorbate, is buffered vitamin C (i.e. a gentle or non-acidic form of vitamin C) proven to be more easily absorbed by the organism than regular vitamin C (ascorbic acid).
Buffered Vitamin C is non-acidic
Buffered Vitamin C has the same benefits of regular vitamin C with no stomach upset and it can contribute to:
boost the immune system*
increased iron absorption
Immune System Boost, Collagen Formation... the Many Benefits of Vitamin C
*Vitamin C lecture by Suzanne Humphries
Buffered Vitamin C - Calcium Ascorbate (120 x 500mg capsules)