The Short Version
The human body does not have a strict physiological requirement for fast-digesting (simple) carbohydrates specifically. While authoritative medical sources confirm that carbohydrates broadly are important for energy and brain function, none establish that simple carbs in particular — as distinct from complex carbs or endogenously produced glucose — are uniquely required. The body can generate glucose through gluconeogenesis from non-carbohydrate sources. However, the claim omits practical scenarios where fast-acting carbs are medically beneficial, such as treating hypoglycemia.