yellow snow
New member
I did a cut and paste on the following, but T2 has got brought up so I thought I would post this: Here's an old Pro/Con list I found, but it's from 2007. Not 100% up to date.
"
3,3'-Diiodothyronine
Advantages
* Almost no suppression of TSH/hypothalamic-pituitary-thyroid axis
* Stimulates cytochrome c oxidase - aka decouples Electron Transport Chain (slightly more than 3,5-T2)
* Precursor to T3 & T4 (which have their own metabolic properties of course)
Disadvantages
* Interferes with plasma membrane transport of T3
* No significant increases in growth hormone seen at any dosing levels
3,5-Diiodothyronine
Advantages
* Increases serum levels of growth hormone (GH) comprable to T3
* Stimulates cytochrome c oxidase - aka decouples Electron Transport Chain (slightly less than 3,3'-T2)
* Does not interfere with plasma membrane transport of T3
* Increases activation of Glucose-6-Phosphate Dehydrogenase
Disadvantages
* Suppression of TSH/hypothalamic-pituitary-thyroid axis is only slightly less but comprable to that of T3
Summary
If one is looking for strictly an increase in energy expenditure with less TSH depression, 3,3'-T2 is your answer..... If one is looking for more muscle mass preservation properties aswell and doesn't mind some TSH depression, 3,5-T2 is your answer...."
Also saw a couple people mention that 3,3 is shown to increase the rate of metabolism in Skeletal muscle tissue. Whereas 3,5 is shown to increase metabolism in tissues such as brown adipose tissue.
A combo would probably be most effective, but I've only scratched the surface reading wise
"
3,3'-Diiodothyronine
Advantages
* Almost no suppression of TSH/hypothalamic-pituitary-thyroid axis
* Stimulates cytochrome c oxidase - aka decouples Electron Transport Chain (slightly more than 3,5-T2)
* Precursor to T3 & T4 (which have their own metabolic properties of course)
Disadvantages
* Interferes with plasma membrane transport of T3
* No significant increases in growth hormone seen at any dosing levels
3,5-Diiodothyronine
Advantages
* Increases serum levels of growth hormone (GH) comprable to T3
* Stimulates cytochrome c oxidase - aka decouples Electron Transport Chain (slightly less than 3,3'-T2)
* Does not interfere with plasma membrane transport of T3
* Increases activation of Glucose-6-Phosphate Dehydrogenase
Disadvantages
* Suppression of TSH/hypothalamic-pituitary-thyroid axis is only slightly less but comprable to that of T3
Summary
If one is looking for strictly an increase in energy expenditure with less TSH depression, 3,3'-T2 is your answer..... If one is looking for more muscle mass preservation properties aswell and doesn't mind some TSH depression, 3,5-T2 is your answer...."
Also saw a couple people mention that 3,3 is shown to increase the rate of metabolism in Skeletal muscle tissue. Whereas 3,5 is shown to increase metabolism in tissues such as brown adipose tissue.
A combo would probably be most effective, but I've only scratched the surface reading wise
