Can anyone comment on Andy cutlers views on TTFD here: (taken from onibasu wiki)
I'm not prepared to wade through all the detail of the disjointed exchange on that forum, nor am I prepared to track down the original studies from Japan on the safety of the allithiamines, including TTFD to give references.
With those provisos, it appears that Culter is making claims designed to fit his pet theories, rather than commenting on the efficacy of TTFD as a thiamine.
Much of his criticism centres on whether or not TTFD acts as a chelating agent. I don't think any one has suggested that it is, nor would one expect it to. Its action as thiamine is the issue and the heavy metal issue is a red herring.
An even bigger red herring is the claim that since benfotiamine is monophosphorylated and thus needs only one further phospharylation to form active thiamine, while TTFD needs two phosphorylations, the former form is metabolically less demanding.
As per my previous posts, the phosphate group on benfotiamine is no advantage - it is clipped before the molecule is taken up into the cell.
Studies on benfotiamine indicate that it is taken up into the cell in the same way as thiamine. The difference appears to be that it is absorbed from the gut better than thiamine and so higher concentrations of thiamine within the cell are achieved.
The mechanism of uptake of the allithiamines is different. Their lipophilic nature means they can cross cell membranes readily (including the BBB) and don't rely on thiamine transporters. High levels of thiamine can be achieved within the cell.
With both types of thiamine, once in the cell, both need to be phosphorylated in the same way.
I was very interested in Culter's claim of an adverse reaction rate of 20%. For someone who prides himself on his command of statistics, all I can say is that this calculation is decidedly flaky and based on very thin data from a tiny pilot study from Lonsdale on 10 autistic children (notorious for sensitivities) and people self-reporting to him of problems with the supplement.
Well I think everyone on PR can relate to adverse reactions to supplements, how individual it is and how mostly the reason is unknown or dependent on changeability of other things. Various health conditions seem to be associated with increased sensitivities.
Cutler has advanced the theory that the reason for the adverse reaction is the toxicity of the tetrahydrofurfuryl group. He weaves this in to his own narrative and pet theories by claiming the presence of a free thiol is the issue.
He presents no evidence whatsoever on the toxicity of the prosthetic group and ignores the extensive studies of the Japanese on the allithiamines as well as Lonsdale's other studies.
I can readily accept the some people have trouble with TTFD and so it is not a thiamine supplement to be universally recommended. Nor is it to be universally condemned on spurious grounds.