Why do people who are very active require plenty of thiamin?

People who are very active require plenty of thiamin (vitamin B1) because it plays a crucial role in energy metabolism. Thiamin helps convert carbohydrates into glucose, which is the primary fuel source for physical activity. Additionally, it supports the proper functioning of the nervous system and muscle contraction, both essential for maintaining high levels of activity. A deficiency in thiamin can lead to fatigue and decreased performance, making adequate intake vital for active individuals.