We have combined all 8 B-vitamins in this supplement: B1 (thiamine) contributes to normal energy-yielding metabolism. B2 (riboflavin) and B3 (niacinamide contribute to the maintenance of normal skin, vision and reduction of tiredness and fatigue. B5 (pantothenic acid) contributes to normal synthesis and metabolism of steroid hormones, vitamin D and some neurotransmitters. B6 (pyridoxine) contributes to normal energy-yielding metabolism. For B8 (biotin), B9 (folic acid) and B12 (cyanocobalamin) see the individual sections.