A, B, C, D, E, K

Vitamin A (Retinol), Vitamin B1 (Thiamine), Vitamin B2 (Riboflavin), Vitamin B3 (Niacin), Vitamin B5 (Pantothenic Acid), Vitamin B6 (Pyridoxide), Vitamin B7 (Biotin), Vitamin B9 (Folic Acid), Vitamin B12 (Cobalamins), Vitamin C (Asorbic Acid), Vitamin D2 (Ergocalciferol), Vitamin D3 (Chloecalciferol), Vitamin D4 (Dihydroergocalciferol), Vitamin D5 (Dihydrotachysterol), Vitamin E (Tocopherol) Vitamin K1 (Phylloguinone), K2 (Menatetrenone), K3 (Menadione), K4 (Menadiol)

That is a complicated question with no one single answer. But a good start is "More than the current government RDI"

Many Vitamin D researchers are recommending that adults take a MINIMUM of 2000 IU's per day and are petitioning the government to take action immediately!

But the 'Best' answer, is that you should get your Vitamin D levels checked and keep your blood levels within the "Optimum Range" as outlined by several different researchers and studies- with the main consensus being between about 50-80 ng/ml.

This blood level seems to be the optimum for good health and has been shown over and over again to have no ill effects.