Overview
Vitamin B1 (thiamine) is a water-soluble vitamin essential for energy metabolism, acting as a coenzyme in carbohydrate metabolism and mitochondrial function. It plays a critical role in nervous system health by supporting nerve conduction and maintaining myelin sheath integrity. Deficiency leads to conditions such as beriberi and Wernicke-Korsakoff syndrome, particularly in individuals with alcohol use disorder or malabsorption. Emerging evidence suggests high-dose thiamine may improve metabolic disturbances, including hepatic steatosis under overnutrition conditions, by enhancing oxidative catabolism [6]. Thiamine, along with other neurotropic B vitamins (B6 and B12), is also implicated in the management of peripheral neuropathy due to its role in neuronal energy production and antioxidant defense [4][7]. While no direct cancer prevention role is established, excessive intake of certain B vitamins has raised concerns about potential promotion of cancer progression, though specific data on B1 are limited [3].
Dosage Guide
Recommended Daily Allowance
For generally healthy individuals
Therapeutic Doses
For treatment of specific conditions
Upper Intake Limit
Maximum safe daily intake
mg— No Tolerable Upper Intake Level established for thiamine due to low toxicity; high doses generally well tolerated
Special Forms
Alternative forms for specific needs
Fat-soluble thiamine prodrug with higher bioavailability; used in diabetic neuropathy and neurodegenerative conditions
Clinical Notes
- Thiamine deficiency must be corrected before initiating glucose-containing fluids in malnourished or alcoholic patients to prevent Wernicke's encephalopathy.
- High-dose thiamine is generally safe, but parenteral administration may rarely cause anaphylactoid reactions.
- Benfotiamine may offer superior tissue penetration and is preferred in neuropathic conditions despite higher cost.
- Monitor for thiamine deficiency in patients with chronic alcohol use, bariatric surgery, or malabsorptive disorders.
Research
Meta-analysis focused on combined B-vitamin supplementation (folic acid, B12, B6) for stroke prevention; did not isolate effects of B1.
Pooled cohort study on B-vitamin intake and bladder cancer risk; found increased risk with moderate intake of some B vitamins, but did not isolate B1.
Review highlighting dual role of B vitamins in cancer—deficiency vs. excess—suggesting potential risks with high-dose supplementation, though B1-specific data lacking.
Expert consensus supports use of neurotropic B vitamins (B1, B6, B12) in managing peripheral neuropathy, citing mechanistic and clinical evidence.
Safety update on metformin-induced B12 deficiency; not directly related to B1.
High-dose thiamine therapy prevented hepatic steatosis and improved metabolic profile in sheep under overnutrition.
Review detailing biochemical roles of B1, B6, and B12 in the nervous system, emphasizing energy metabolism, antioxidant effects, and nerve function.
Cochrane review on B vitamins for diabetic kidney disease; included B1 derivatives but found insufficient evidence to support routine use.
Products Containing B1(2 reports)
This multivitamin formulation delivers essential vitamins at moderate doses, with vitamin D3, vitamin A, and B-complex vitamins as primary contributors to nutritional support. The inclusion of clinically relevant forms such as D3 (cholecalciferol) and methylfolate-capable dosing suggests a focus on bioavailability and metabolic utility.
This multivitamin supplement from Nestlé provides clinically relevant doses of vitamin D and calcium as primary nutrients, supporting bone and immune health. Vitamin D (12 mcg) aligns with therapeutic dosing for insufficiency, while calcium (350 mg) contributes meaningfully to daily requirements. Other vitamins and minerals are included at supportive levels, enhancing overall micronutrient intake without targeting specific deficiencies.