T3, better known as liothyronine sodium, triiodothyronine and cytomel, is a fascinating thyroid hormone drug that is medically used by those who have thyroid problems. However, bodybuilders also use T3 to help them increase their metabolism and burn fat.
Fig 1. T3 chemical structure
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Understanding the thyroid
TSH stands for thyroid stimulating hormone, and blood work can show if a person has hyper or hypo thyroidism, which means an over (hyper) or underactive (hypo) thyroid respectively. TSH is produced when TRH (thyrotropin-releasing hormone) is released in the brain, triggering the pituitary glands to produce T3 in order to control the body's metabolism. This is why those with a slower metabolism (hypothyroidism) will sometimes get prescribed T3 by their doctors to help them avoid the negative side effects of this condition, such as fatigue, weight gain, slow heart rate, depression, joint issues, and puffy face. My opinion is that an insufficient lifestyle and diet are the major contributors in those with this issue, and it is common in older women.
What happens when we use T3
Unfortunately, those prescribed T3 will sometimes be put on the drug for life, as that is what doctors do - treat conditions with medication. Nonetheless, bodybuilders do not want to go down this road and will choose to cycle T3 instead (use it for a period of time, and then come off for a period of time). For example, in a normal male, the body produces around 25 micrograms (mcg) of T3, so just like anabolic steroids, when you run any T3 dose it will suppress your own body's production of the hormone. Hence, if you run 25mcg of T3, you will be replacing the 25mcg you naturally produce with exogenous T3, so most bodybuilders will run at least 40 or 50mcg to get real results.
When you run twice as much T3 as your body is producing, you are obviously creating an environment of an overactive thyroid. As a result, everything in your body will ramp up and burn - from fat, to muscle. Sadly, this is the mistake many guys make, as they use T3 improperly and burn away precious muscle and strength that they worked so hard to gain!
Catabolism from T3
Okay, technically T3 isn't really catabolic at all, but that word can mean many things, and the bottom line is that running T3 alone would be foolish for the above mentioned reasons. As you may imagine, no bodybuilder wants to ever lose muscle. In fact, I have never heard any male say they actually want to lose muscle. So how can we prevent losing precious muscle, and still take advantage of the boost in metabolism from T3?
The solution is stacking T3 with anabolic steroids. Some of you will worry about suppression from anabolic steroids, but remember - T3 causes thyroid suppression, as it's a hormone too. Therefore, if you are going to run T3, stacking it with steroids is the best route to take.
T3 should be ran at a minimum of 40-50 mcg per day because the body produces 25mcg on its own, and you want to go past that mark. Some say that splitting dosages throughout the day is necessary, but I do not agree with that; as a result, I suggest once a day dosage. Interestingly, the more advanced lifters will run T3 at 75, or even 100mcg daily. What's more, I have heard guys run it for up to 6 months at a time, which I do not feel is a good idea, so I would recommend running it for 8 weeks at a time maximum until you get very experienced.
Obviously, if you are using T3, your goal is 'cutting,' so adding Cardarine (GW-501516) makes a lot of sense; plus, it is non hormonal, so it won't add to your suppression issues. Furthermore, such 'cutting' anabolic steroids as winstrol, masteron, proviron, primobolan, and anavar are great options to stack in with T3, as they do not cause water retention or increase appetite. Some guys will also use a small dose of testosterone, or trenbolone combined with T3. Using any of these anabolic steroids will prevent loss of muscle and strength from T3, so they are a must to use.
T3 side effects
T3 can cause fatigue, shakiness, sweating, and heart strain issues. If you start experiencing this, you should lower your dose immediately. Additionally, what you choose to stack with T3 can make these symptoms worse as well. Thus, if you are running every anabolic steroid under the sun with clenbuterol, and then want to stack T3 in there too, then expect lots of side effects. A major mistake a lot of guys make is they want overnight results, instead of doing it the right way and being conservative. Keep in mind, T3 isn't a magic pill, and you will need to run it for a period of time along with proper nutrition and exercise if you want to see results.
Yes! it is true, there is a lot of fake T3 being sold by research companies out there. As a result, many guys complain about getting zero results from T3, and like everything in life, some will react very well and some will not. The mistake to avoid is getting your T3 from a poor source, where it is underdosed, or even totally bunk.
T3 abuse and addiction
Just like anabolic steroids, some bodybuilders abuse T3 long term and stay on it forever, which is more common in pro bodybuilding, where they want a constant increase in metabolism all the time. From all the medical evidence we have, there is zero reason to think that using T3 long term will result in ruining your thyroid. However, having spoken to many who have abused T3, it will become difficult to stay away from it if you start abusing it. The reason for this is that you may find it necessary to use T3 in order to stay at the body fat you want, and it could boil down to psychological factors of being dependent on it. Having said all that, there are many who swear their T3 abuse has led to them having thyroid problems. Thus, it is essential to keep T3 cycles at 8 weeks or less and do not exceed 75-100mcg per day total, unless you really know what you are getting into.
Once you stop T3, it will take some time for your thyroid to recover, and your body to produce the normal 25mcg per day. Luckily, there is a supplement called "T3 PCT" sold by N2BM.com. It can be taken to help you get through that period without putting back on tons of fat.
Want to read about T3 on our forums? check out these threads: