As described above, individuals with alcoholism have a high risk of thiamine deficiency because of poor nutrition, impaired absorption of thiamine from the gastrointestinal tract, and reduced liver stores.112 Moreover, alcohol interferes with the conversion of thiamine to its metabolically active form, namely TPP.113 A reduction in TPP levels disrupts the following processes: carbohydrate metabolism, thereby interrupting energy production through the Krebs cycle and pentose phosphate pathway; lipid metabolism, thereby interrupting the production and maintenance of myelin; and amino acid metabolism, thereby interrupting the production of glucose-derived neurotransmitters.10 These metabolic deficits can contribute to neuronal and white matter damage.
