Vitamin A is needed by the retina of the eye in the form of a specific metabolite(the light-absorbing molecule retinal). This molecule is absolutely necessary for both scotopic and color vision. It also palys an important role in the health or our skin, bone metabolism, immune function. It is also commercially produced and administered as esters such as retinyl acetate commonly called Vitamin A acetate. Its defeciency can cause blindness. Other problems include impaired immunity, hypokeratosis (white lumps at hair follicles), keratosis pilaris and squamous metaplasia of the epithelium lining the upper respiratory passages and urinary bladder to a keratinized epithelium.

Vitamin D3 can be taken in supplement form as well especially in countries where sunlight is minimal or if the person is not exposed to sun. It is important for the absorption of calcium and phosphorous. It helps in prevention of fractures, osteoporosis, cancer and high blood pressure. Vitamin D3 helps in treating vitamin D deficiency such as Rickets and Osteomalacia. It’s especially important for pregnant women, post menopausal women and older people as its deficiency can lead to osteoporosis, hip fractures and slows growth of fetus. It can also be fatal to both mother and child and in some cases result in multiple sclerosis at a later stage of the child.