Beriberi is a Vitamin B1 (Thiamin) Deficiency

3. Wernicke Encephalopathy and Korsakoff Syndrome

When thiamin levels fall too low, brain cells cannot produce enough energy to function properly, which can lead to the brain disorder Wernicke-Korsakoff syndrome. The syndrome is the combination of two conditions: Wernicke encephalopathy and Korsakoff syndrome. Wernicke encephalopathy causes damage to the lower parts of the brain — the thalamus and the hypothalamus — and can be fatal if not treated. As its symptoms start to fade, Korsakoff syndrome, a chronic, short-term memory disorder, develops.