Thiamine (Vitamin B1)
Thiamine is an essential B vitamin crucial for glucose metabolism and mitochondrial function, particularly important for individuals with heavy alcohol use or those undergoing bariatric surgery. It supports cardiac and neurological function.
Evidence last reviewed: 20 Apr 2026
Thiamine supplementation is well-supported for preventing deficiency, especially in bariatric surgery patients, with a high prevalence of deficiency noted. Evidence also suggests benefits for cognitive function and neurological symptoms, though more research is needed on broader populations.
Cognitive functionPatients with dementia · Systematic reviewModerate
Thiamine supplementation showed a positive impact on cognitive performance, especially when combined with folic acid.
Neurological symptoms in Wernicke's encephalopathyPatients with Wernicke's encephalopathy · Systematic reviewModerate
IV thiamine alleviated neurological symptoms and cognitive dysfunction associated with Wernicke's encephalopathy.
Thiamine deficiency prevalencePost-bariatric surgery patients · Meta-analysisHigh
27% of patients undergoing bariatric surgery experience vitamin B1 deficiency, indicating the need for lifelong supplementation.
Neurological and clinical findings in Wernicke's encephalopathyPatients with Wernicke's encephalopathy · Case seriesLow
IV thiamine led to partial or complete resolution of symptoms in 90% of cases.
Forms & usage▾
Take 100 mg daily, preferably with meals.