Vitamin B-1 (thiamine) functions in which of the following ways?

• A. It is not required for energy metabolism
• B. It acts only in vision
• C. It aids in converting food into energy and supports cardiovascular and nervous system function
• D. It is mainly involved in bone health

Answer: (C)

Thiamine (vitamin B1) functions as a coenzyme in carbohydrate metabolism, enabling the body to efficiently convert food into energy. In its active form, thiamine pyrophosphate, it is essential for enzymes such as pyruvate dehydrogenase and α-ketoglutarate dehydrogenase in the mitochondrial energy-producing pathways, as well as transketolase in the pentose phosphate pathway. This enables the aerobic production of ATP, which is crucial for tissues with high energy demands, particularly the nervous system and the cardiovascular system. Because energy production underpins nerve function and heart muscle performance, thiamine supports both nervous system and cardiovascular function, making that its most accurate description.

It isn’t correct to say it isn’t needed for energy metabolism, since thiamine is a critical cofactor for turning glucose into usable energy. It isn’t limited to vision, as thiamine has no specialized role in the visual system. And it isn’t mainly involved in bone health, since bone metabolism isn’t a primary function of thiamine.