2. B Vitamins This group includes several vitamins, such as B1 (Thiamine), B2 (Riboflavin), B3 (Niacin), B5 (Pantothenic Acid), B6 (Pyridoxine), B7 (Biotin), B9 (Folic Acid), and B12 (Cobalamin). They support metabolism, energy production, and maintain a healthy nervous system.