Vitamins such as B-complex vitamins (including B1, B2, B3, B5, B6, B7, B9, and B12) are crucial for energy metabolism. They are involved in converting carbohydrates, proteins, and fats into usable energy. Additionally, vitamins like C and E play roles in cell protection and recovery processes. A deficiency in these vitamins can lead to energy deficits, fatigue, and hindered performance. Therefore, maintaining adequate vitamin intake through diet or supplementation is essential for optimal energy levels.