A deficiency of which vitamin results in beriberi, with the meaning "I can't, I can't"?

Beriberi is primarily associated with a deficiency of Vitamin B1, also known as thiamin. This vitamin plays a crucial role in energy metabolism and is essential for the proper functioning of carbohydrates in the body. When thiamin is deficient, the body's ability to convert food into energy is impaired, leading to various symptoms that can affect the cardiovascular and nervous systems. The phrase "I can't, I can't" reflects the fatigue and muscle weakness often experienced by individuals suffering from beriberi, underscoring the debilitating effects of the deficiency.

Thiamin is vital for the synthesis of adenosine triphosphate (ATP), the energy currency of the cell. It is also involved in the decarboxylation of pyruvate to acetyl-CoA, a key step in aerobic respiration. Without sufficient thiamin, these metabolic pathways cannot function optimally, leading to symptoms such as exhaustion, difficulty walking, and nerve damage characteristic of beriberi. Thus, understanding thiamin's critical functions helps clarify why its deficiency leads to the debilitating condition associated with beriberi.