Over a whisky (or two) I've been thinking about the scientific base for arguing that NDT has the "wrong" T4/T3 ratio compared with the natural ratio in healthy humans, and therefore is putting people at risk by giving too much T3 relative to T4 in treatment. I think now this argument doesn't hold water for this reason. So long as the amount of T3 taken in is that giving a normal FT3, then it does not matter how much or how little the accompanying T4 is held in reserve (so long as there is some reasonable amount available as a conversion backup and it doesn't get significantly depleted over the day). By this I mean that, if a patient is relatively deficient in T4-T3 conversion, and has little or no remaining active thyroid gland, then the normal T4/T3 ratio for healthy people won't be appropriate. This will be even more the case if our indication recently of a significantly greater direct T3 contribution of the thyroid gland holds up. The missing thyroid T3 has to be replaced by taking it directly if the gland's contribution is no longer there and the tissues can't make enough to replace it. In fact, one of our number plans to re-examine this question of T3 production by either gland or by tissue conversion using a more controlled study than has been done hitherto. If it turns out that the direct thyroid contribution of T3 is as high as 35-40% rather than the 20% now believed to be the case, then the arguments against NDT's wrong ratios collapse.
T3-only medication is one I still have problems with. But they would be assuaged if there was available a "slow release" T3 tablet, so that one didn't get the "waves" of temporary overtreatment immediately after taking the hormone. Perhaps in the future such tablets will come into being.