Vitamin C 500mg Tablets | Biocare (60). Vitamin C 500 provides a bioavailable source of vitamin C and magnesium, together with bilberry extract. Magnesium ascorbate is buffered which means as a less acid form of vitamin C it is therefore gentler on the stomach.. Provides a readily absorbable form of vitamin C and magnesium. 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 one of the richest sources of natural flavonoids. Suitable for individuals requiring a citrus-free vitamin C supplement. Vitamin C contributes to maintain the normal function of the immune system during and after intense physical exercise. Vitamin C contributes to normal collagen formation for the normal function of blood vessels, bones, gums, skin teeth & cartilage. Vitamin C and magnesium contribute to normal psychological function. Vitamin C contributes to the protection of cells from oxidative stress. Magnesium contributes to a reduction of tiredness and fatigue. Magnesium contributes to normal muscle function. Bilberry anthocyanosides can help capillary vessels health and elasticity of veins against harmful effects of free radicals