
Originally Posted by
juiceinthehood
a post from mallet at our site
T4 is a little trickier to dose..the rule of thumb is four times as much t4 to t3, basically your body produces about 75mcg a day of t4 and roughly one third of that is converted to t3 (25mcg). t3 is four times more active than t4 at the target cells. The main difference between taking t4 and taking t3 is you have no control of the conversion rate of t4 to t3, so it's imparitive that your diet be high in Selenium (200mcg) and zinc (50mg) without selenium and zinc, the enzyme iodothyronine deiodinase cannot do its job of converting t4 to t3. One enzyme that is particularily of interest is adenylate cyclase, this enzyme activates the molecule cyclic adenosine monophosphate (cAMP)supplementing with Coleus Forskolii will help with cAMP. T4 has a slower onset of endogeous shutdown, therefore cycling can be slightly longer without breaking. The answer still lies in monitoring your basal body temp every morning to see how your metabolism is responding to the supplementing of thyroid hormones. The half life of t4 is shorter as well due to the fact that a percentage of t4 is readily converted to t3, so splitting up your dose throughout the day is recommended!