T3 is Protective Against Cancer
This is a health study that implies that FT4 and FT3 levels when in a good range are protective of health. FT3 and FT4 tend to protect again many sources of mortality including cardiovascular related mortality. FT3 levels especially being at a good level protect against cancer.
Here is the study and the link to it:
Thyroid hormones and mortality risk in euthyroid individuals: the Kangbuk Samsung health study.
Zhang Y, Chang Y, Ryu S, Cho J, Lee WY, Rhee EJ, Kwon MJ, Pastor-Barriuso R, Rampal S, Han WK, Shin H, Guallar E. J Clin Endocrinol Metab. 2014; 99(7):2467-2476.
The implications of this are pretty clear.
Those that are on T3, T4/T3 and NDT treatment and have good levels of FT3 and feel properly treated (no symptoms), are in a lower risk situation re: cancer likelihood.
Those thyroid patients on T4 therapy that is not converting well enough, that have remaining symptoms are likely to have too low an FT3 level and are more at risk of health issues.
The sooner the entire medical profession wises up to this and the ability to lower costs by avoiding future problems for their patients the better.
All patients deserve to be as healthy as possible.
Far too much emphasis is placed on keeping everyone on the same, simplistic T4 treatment (also the cheapest) without considering the long term costs of other conditions that can come out of this.
Cancer especially is a very expensive condition to treat.
It is only right to provide a variety of therapies and put the effort in to finding the one that works for the individual.