Vitamin A is a fat-soluble vitamin essential for various bodily functions. It exists in several forms, including retinol, retinal, and retinoic acid, which are collectively known as retinoids. Additionally, provitamin A carotenoids, such as beta-carotene, can be converted into vitamin A in the body.

Vitamin D2 (ergocalciferol) is mainly used to prevent and treat rickets, osteomalacia, and infantile tetany.

Vitamin K2, also known as menaquinone, is a fat-soluble vitamin essential for activating certain proteins involved in blood clotting and bone metabolism. It is vital for the activation of osteocalcin, a protein that helps bind calcium to the bone matrix, promoting bone strength and density. Additionally, vitamin K2 helps regulate calcium distribution in the body, directing it away from arteries and towards the bones, which supports cardiovascular health.