Comparison guide

Which vitamin B1 should you take?

Plain thiamine fixes deficiency; the fat-soluble derivatives benfotiamine and TTFD raise blood thiamine far more, and sulbutiamine is marketed for fatigue and focus rather than for thiamine status. What matters is whether you are correcting a deficiency, looking at neuropathy symptoms, or buying a nootropic claim with little behind it.

The options, compared

Option	Evidence	Best for	The honest note
Vitamin B1 (Thiamine)	Moderate evidence	Correcting or preventing deficiency	Cheap, extremely well tolerated and life-saving in deficiency, which is common in alcohol use disorder, after bariatric surgery and with diuretics; topping up a normal level does not boost energy.	View
Benfotiamine	Moderate evidence	Diabetic neuropathy symptoms	Absorbed several-fold better than thiamine, but only 600 mg/day beat placebo on neuropathy symptoms in a short trial; common 150–300 mg doses are at or below what showed anything.	View
TTFD (Allithiamine)	Limited evidence	Little reason to choose it	Raises blood thiamine better than plain thiamine, but the clinical data are a 10-child uncontrolled pilot and a negative exercise trial, and users report a sulfurous body odour.	View
Sulbutiamine	Limited evidence	Not a way to fix thiamine	A nootropic-style derivative resting on small, mostly uncontrolled studies, with reports of insomnia, agitation and misuse at high doses; it is a prescription drug in some countries.	View

Our verdict

Plain thiamine is the right choice for deficiency and costs little. Benfotiamine is the derivative worth considering for diabetic neuropathy symptoms, with modest evidence at 600 mg/day, but get numbness or tingling diagnosed first. TTFD reaches the blood well but has almost no clinical data, and sulbutiamine is a stimulant-like nootropic rather than a thiamine supplement, so most people can skip both.