Vitamin c 1000 is a powerful tablet containing 1000mg of magnesium ascorbate a low acid form of vitamin c together with synergistic antioxidants in the form of bilberry and grapeseed extract a buffered low acidity form of vitamin c to reduce stomach irritation magnesium ascorbate does not leach minerals such as calcium and potassium from the body bilberries are a potent source of citrus free flavonoids which help support capillary and connective tissue integrity