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Limited evidenceVitamins & minerals

TTFD (Allithiamine)

A fat-soluble thiamine derivative that raises blood thiamine much more than plain thiamine. What it does clinically is almost unstudied: one 10-child uncontrolled pilot and a negative exercise trial are the bulk of the human data.

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What the science says

  • Raises thiamine levels better than plain thiamine Moderate evidence

    A crossover bioavailability study in 7 volunteers compared 100 mg doses of benfotiamine, fursultiamine (TTFD) and thiamine disulfide; the lipid-soluble derivatives produced far higher plasma and red-cell thiamine than water-soluble thiamine, with benfotiamine highest.

  • No effect on exercise performance Limited evidence

    A randomized double-blind crossover in 14 cyclists given 1 g/day TTFD for 4 days found no difference from placebo in VO2peak, lactate threshold, submaximal oxygen uptake or 2000 m time-trial performance.

  • Autism pilot is not evidence Limited evidence

    An uncontrolled pilot in 10 autistic children reported clinical improvement in 8 after two months of TTFD suppositories. With no control group and ten participants, this cannot support any claim; it is the study most often cited for TTFD.

Dosage & safety

Studied doseSupplements usually supply 50–100 mg/day. Study doses ranged from 100 mg (bioavailability work) to 1 g/day (the exercise trial). No dose has been validated against a clinical outcome.
SafetyA sulfurous body odour and nausea are commonly reported by users. There is no long-term safety data at supplement doses and none in pregnancy. Genuine thiamine deficiency with neurological or cardiac signs is a medical emergency treated with parenteral thiamine, not with a supplement.

How to take it

TimingMorning — many users find it stimulating and sleep worse if they take it late.
With food?With food, which reduces the nausea it commonly causes.
Worth knowingThe sulfurous body odour is inherent to TTFD; benfotiamine or plain thiamine avoid it if that is a dealbreaker.

Frequently asked questions

Is TTFD (allithiamine) better absorbed than regular thiamine?

Yes: a crossover study in 7 volunteers found TTFD and other fat-soluble derivatives produced far higher blood thiamine than plain thiamine, a moderate-grade finding, with benfotiamine highest. Higher levels do not show that TTFD does anything clinically.

Does TTFD improve exercise performance?

No: a randomized double-blind crossover in 14 cyclists given 1 g/day TTFD for 4 days found no difference from placebo in endurance or time-trial performance.

Does TTFD help autism?

The evidence is limited to an uncontrolled pilot in 10 autistic children, 8 of whom were reported to improve on TTFD suppositories. With no control group and ten participants, it cannot support any claim.

What are the side effects of TTFD?

Users of TTFD commonly report a sulfurous body odour and nausea, and many find it stimulating, so take it in the morning with food. There is no long-term safety data and none in pregnancy.

Scientific references

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