What role do B vitamins play in the body?

B vitamins play a crucial role in the body as coenzymes in various metabolic processes. They are integral to converting food into energy, enabling the body to utilize carbohydrates, fats, and proteins efficiently. Each B vitamin has a specific function, such as aiding in the metabolism of macronutrients or playing a role in the synthesis of neurotransmitters, which are essential for proper nervous system function.

Coenzymes are molecules that assist enzymes in catalyzing biochemical reactions. B vitamins often serve as the non-protein part of the enzyme complex, which is necessary for the enzyme's activity. This means that without adequate B vitamins, metabolic processes can slow down, leading to decreased energy production and impaired cellular function.

The other choices highlight aspects that are not the primary functions of B vitamins. While some antioxidants are found in the body, B vitamins are not primarily known for serving that role. They are not major sources of energy themselves, as they do not provide calories but instead facilitate the energy production from macronutrients. Additionally, while some B vitamins are involved in amino acid metabolism and protein synthesis, synthesizing proteins is not their primary role; they are more influential as coenzymes in supporting those processes.