Central nervous system energy needs

The brain and other areas of the central nervous system (CNS) have high ATP requirements. Although the brain only represents about 2% of the body s mass, it consumes around 20% of the metabolized oxygen and ca. 60% of the glucose. The neurons high energy requirements are mainly due to ATP-de-pendent ion pumps (particularly Na7K " AT-Pase) and other active transport processes that are needed for nerve conduction (see p. 350). 

Nervous system symptoms—The central nervous system depends solely upon glucose for its energy. So, without thiamin to provide this need, neuronal activity is impaired, alertness and reflex responses are diminished, and fatigue and apathy (lack of interest) follow. If thiamin deficiency... 

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