Viridian High Potency Calcium & Vitamin D3 is a unique combination of 400mg of calcium in three active forms; as calcium hydroxide from Lithothamnion sp, as calcium citrate and as calcium ascorbate alongside 200IU vegan vitamin D3 from lichen. BenefitsCalcium and Vitamin D are needed for the maintenance of normal teeth and bones. Calcium also contributes to normal neurotransmission and muscle function. How to UseAs a food supplement take one to three capsules of Viridian High Potency Calcium & Vitamin D3 daily with food or as directed by your healthcare practitioner.