B vitamins contribute to normal energy yielding metabolism and the reduction of tiredness and fatigue. Vitamin B12 contributes to normal red blood cell formation and has a role in the process of cell division. It also contributes to normal homocysteine metabolism. Protease is a digestive enzyme which supports the breakdown of proteins. B vitamins contribute to normal energy yielding metabolism and the reduction of tiredness and fatigue. Vitamin B12 contributes to normal red blood cell formation and has a role in the process of cell division. It also contributes to normal homocysteine metabolism. Protease is a digestive enzyme which supports the breakdown of proteins.