Thiamine deficiency results in decrease energy production, because TPP:
High-Yield Explanation
Link reaction & TCA cycle requires 5 coenzymes: Lipoic acid and four B-complex Vitamins (B1, B2, B3, B5). Due to this reason, Thiamine (vitamin B1) deficiency results in decrease energy production (also CNS problems because Brain cells depend on this aerobic reaction) as TCA & link reaction both are responsible for energy production in cells.