It’s common for people with hypothyroidism and Hashimoto’s Thyroiditis to have low levels of triiodothyronine, also known as T3. Sometimes the T3 levels will be within the lab reference range, but less than optimal. On the other hand, sometimes they will be outside of the lab reference range. Either way, the goal is to try to bring the T3 to an optimal level, and in this blog post I’ll discuss seven ways to increase low T3 levels.
Before I discuss the seven ways to increase low T3 levels, you might wonder why I’m not talking about T4 in this post. In 2016 I did release a blog post entitled “7 Causes of Low T4 Levels [1]”, and while some of the same factors will cause low T3 levels, there are different causes as well. In addition, I usually recommend to test for the free T3 levels, and from an optimal perspective you want to see these levels between 3.0 and 3.5 pg/ml, although some sources will suggest a tighter range (i.e. between 3.2 and 3.5 pg/ml).
It’s also important to mention that not all medical doctors will test the T3 levels. Many will only test the TSH and T4, while some will test the TSH alone. The reason for this is because in most cases the T3 isn’t going to change their recommendations, as most medical doctors will 1) base their recommendations off of the TSH, and 2) prescribe synthetic thyroid hormone to just about all of their patients with a hypothyroid condition. If this describes your doctor then you might want to consider switching to a different doctor, or another option is to try to order free T3 on your own.
With that being said, let’s go ahead and look at the seven ways to increase low T3 levels. Please keep in mind that I’m not listing these in the order I recommend.
1. Take synthetic T4. Although I’m starting with synthetic T4 because this is the most common recommendation by medical doctors to address both low T4 and low T3 levels, this isn’t my first preference. And the reason for this is because while taking thyroid hormone replacement is necessary at times, this doesn’t do anything to address the underlying cause of the problem. In addition, Synthroid is the most common brand of synthetic thyroid hormone medication [2] recommended, and it has a lot of fillers, along with artificial ingredients. As a result, if someone absolutely needs to take synthetic T4, they should look into a more hypoallergenic form, such as Tirosint [3].
Some reading this might wonder how taking synthetic T4 will increase low or depressed T3 levels. Well, T4 converts into T3, and so if someone has healthy levels of T4, then they should be able to convert the T4 into T3. However, if someone has a problem converting T4 to T3 then taking synthetic T4 won’t be effective in raising T3 levels.
2. Synthetic T3. If someone has low or depressed T3 levels, then it might make more sense to take synthetic T3 rather than synthetic T4. Synthetic T3 is also known as liothyronine, with Cytomel being a common brand. A recommended starting dosage is 25 mcg per day, although some will start with lower doses (i.e. 5 mcg). While some medical doctors will recommend synthetic T3 if someone has low T3 levels, since T3 is the active form of thyroid hormone, many are cautious about doing this out of fear that the person will develop hyperthyroid symptoms [4].
Earlier I mentioned that it might make more sense for someone who has low or depressed T3 levels to take synthetic T3 instead of synthetic T4, although it depends on the situation. For example, if someone has depressed levels of both T4 and T3, then it wouldn’t make sense to only have the person take synthetic T3. In fact, as I mentioned previously, if the person is able to convert T4 to T3 then in this scenario they might be fine just taking synthetic T4, although in some cases taking both synthetic T4 and T3 might be warranted. On the other hand, if someone has normal levels of T4 and low or depressed levels of T3, then this might be a good indication that synthetic T3 is needed.
However, just as is the case with taking synthetic T4, synthetic T3 doesn’t do anything to address the cause of the problem. And so while taking synthetic T3 might be necessary in some cases, the obvious goal should be to fix the conversion problem and/or address the autoimmune component (for those who have Hashimoto’s), which I’ll discuss later in this post.
3. Natural thyroid hormone [5]. If someone needs to take thyroid hormone replacement, desiccated thyroid hormone should be considered. Brand names include Armour, Nature-Throid, and WP Thyroid. These all include T3 and T4, along with other thyroid cofactors (T1, T2, and calcitonin). This type of thyroid hormone replacement can especially be helpful if someone has low or depressed levels of both T4 and T3. Although over the years I have had many patients take Armour and do fine, I prefer Nature-Throid and WP Thyroid because they are hypoallergenic. And while many people do fine taking synthetic thyroid hormone, some people don’t do well on this, yet thrive when taking desiccated thyroid hormone. On the other hand, a small percentage of people don’t do well on natural thyroid hormone, and actually do better when taking synthetic thyroid hormone replacement.
4. Thyroid glandular supplements. For those who are unable to get a prescription for Armour, Nature-Throid, WP Thyroid, or a different brand of natural thyroid hormone, there are thyroid glandular supplements that contain desiccated thyroid hormone, and don’t require a prescription. Some of these thyroid glandular only include T3, while others have both T4 and T3. It’s common for these thyroid glandular supplements to also include nutrients and/or herbs that support thyroid gland function. Common nutrients included include selenium [6], tyrosine, and zinc, and ashwagandha [7]is an adaptogenic herb that is added to some thyroid glandular supplements.
5. Compounded thyroid hormone medication. Compounded T4/T3 is made by a compounding pharmacist, and is another option to consider. One advantage of compounded T4/T3 is that the doses can be customized. Another advantage is that the product can be formulated to be hypoallergenic. Some compounding pharmacists can also put together a custom formulation using desiccated thyroid. However, getting T4/T3 through a compounding pharmacy can be considerably more expensive.
6. Correct the conversion problem. So far I have focused on different types of thyroid hormone replacement. But even if you need to take thyroid hormone, it makes sense to address the cause of the problem. I mentioned earlier that ideally T4 should convert into T3, but many people have problems converting T4 to T3. If someone’s thyroid panel reveals normal T4 levels and low or depressed T3 levels, then this is a pretty good indication of a conversion problem. However, it’s also possible for BOTH T4 and T3 to be low and to have a conversion problem. When this is the case it can be more challenging to determine if the person has a problem converting T4 to T3, although reverse T3 may be elevated in this situation.
There are numerous factors that can interfere with the conversion process, but three of the more common reasons why people have a problem converting T4 to T3 include 1) liver problems, 2) gut dysbiosis, and 3) elevated cortisol levels. As a result, these are the primary areas I focus on, and while most of the time doing so will correct the conversion problem, in some cases this can be challenging. For more information I would read my blog post entitled “6 Factors Which Can Affect The Conversion of T4 to T3 [8]”.
Should Someone Take Thyroid Hormone Replacement While Fixing The Conversion Problem?
As for whether someone who has a conversion problem should take thyroid hormone, this depends on the person. While the cause of the problem needs to be addressed, we also need to remember that T3 is the active form of thyroid hormone. As a result, if someone has very low or depressed thyroid hormone levels then we don’t want these to be low for too long. The reason for this is because thyroid hormone affects every cell and tissue in the body.
In addition, while sometimes the T3 levels will increase relatively quickly while addressing the cause of the problem, this isn’t always the case. Sometimes it can take many months to correct the conversion problem. There can be a few reasons for this. One reason is because it can take time to address the liver, gut, or adrenal imbalance which are responsible for the conversion problem. Another reason is because sometimes we greatly improve the health of these areas, only to find another factor is responsible for the poor conversion of T4 to T3.
7. Detect and remove the autoimmune trigger. Most people with hypothyroidism have Hashimoto’s Thyroiditis, which is the reason behind their low or depressed T4 levels, and low or depressed T3 levels are common as well. So when someone has low T3 (and T4) levels as a result of Hashimoto’s, the goal is to do everything necessary to detect and then remove the autoimmune trigger. This is easier said than done, and over the years I’ve written many articles and blog posts on some of the different triggers, and I also talk about this during my free webinars. In my upcoming book on Hashimoto’s [9] I’ll go into even more greater detail about triggers, including an entire section dedicated to how to detect all of the different triggers, and another section that focuses on removing your triggers.
While some people with Hashimoto’s don’t need to take thyroid hormone replacement, others need to take it while addressing the cause of the problem. And there are those who need to take it on a permanent basis. It depends on how much damage to the thyroid gland has taken place.
Can There Be Other Factors Responsible For Low T3 Levels?
Although having Hashimoto’s and/or a conversion problem are the most common reasons why someone has low T3 levels, there can be other factors. I’m not going to get into great detail about these here, and ideally you want to work with a natural healthcare professional to address this. But here are some other potential causes of low T3 levels:
Dysregulation of the hypothalamic-pituitary-thyroid (HPT) axis. Although T3 is produced during the conversion process, some T3 is also produced in the thyroid gland. TSH is a pituitary hormone, and it is responsible for signaling to the thyroid gland to release T4 and T3. The hypothalamus communicates with the pituitary gland. As a result, if there are problems with the communication between the hypothalamus and pituitary gland, this in turn can affect the communication between the pituitary gland and thyroid gland, which can result in low T4 and/or T3 levels.
Direct inhibition of the thyroid gland. Although most cases of hypothyroidism are a result of Hashimoto’s, some factors can directly inhibit thyroid hormone production. For example, certain environmental toxins such as mercury [10]can inhibit thyroid hormone production, although sometimes environmental chemicals can cause an immune system response. Either way, in this situation the goal should be to reduce your toxic load.
Some people are concerned about goitrogenic foods inhibiting thyroid hormone production. Although I would be cautious about eating soy, eating cruciferous vegetables usually won’t cause any problems. I spoke more about this in a blog post entitled “5 Things To Know About Goitrogenic Foods [11]”.
Problems with T3 binding to the carrier proteins. Both T3 and T4 are carried through the bloodstream bound to certain proteins. Thyroxine-binding globulin (TBG) is one of these, although it has a higher affinity for T4 than for T3. Both T4 and T3 bind to serum albumin, although these hormones have a higher affinity for TBG. So for example, if the TBG level is low due to a person taking corticosteroids, this will result in lower levels of thyroid hormone in the blood.
In summary, many people with hypothyroidism and Hashimoto’s have low or depressed levels of T3. Unfortunately many medical doctors don’t test the T3 levels, as they will only test for the TSH, and perhaps T4. Ideally you want to increase T3 levels by addressing the cause of the problem, which is usually either damage to the thyroid gland caused by the immune system, or a problem converting T4 to T3. However, thyroid hormone replacement can also increase the T3 levels, and some of the different options include synthetic T4, synthetic T3, desiccated thyroid hormone, thyroid glandular supplements, and compounded T4/T3.