Vitamin E

Vitamin E is a fat-soluable vitamin which aids in the formation of red blood cells and muscles, and protects vitamin A and essential lipids from oxidation. Although never documented as naturally occuring, vitamin E deficiency causes reproductive system failure, liver deterioration, heart damage, and the breakdown of red blood cells. Too much vitamin E can interfere with vitamin K and cause clotting efficiency to decrease.
Good sources of vitamin E:
References: