According to the American Thyroid Association, the Reverse T3 lab is not clinically useful unless you are HOSPITALIZED!

Thyroid Function Tests | American Thyroid Association

What if I told you that Reverse T3 may be where you find the answer to why you don’t feel well even if you are being told that your labs are “normal.” It may also be the reason your symptoms are not improving even when you are receiving the most common thyroid hormone replacement therapy (levothyroxine, brand name Synthroid) used to treat hypothyroid.

Even if your doctor is checking a bunch of thyroid labs, and they are ALL normal, if this piece is missing, then you may not know why you are not feeling better.

In this video, we will be talking about the thyroid hormone known as Reverse T3. This is an INACTIVE form of T3. Reverse T3 does NOT help the cell carry out the same metabolic activity that T3 does. Because Reverse T3 is INACTIVE (and because the American Thyroid Association says it is not clinically useful), many clinicians never check it and believe that it is an “irrelevant” test (unless you are so sick that you are now hospitalized). Unfortunately, that cannot be further from the truth for people with thyroid issues who are not feeling better with treatment.

You learned in the last video that T3 is the most bioavailable hormone that is needed for your cells to carry out metabolic processes. You learned that T3 is the ACTIVE form of thyroid hormone, and it is made from T4 by removing one of the iodine molecules.

What if I told you that T4 can convert to T3 (ACTIVE hormone), AND it can convert to REVERSE T3 (an INACTIVE hormone) depending on which iodine molecule is removed?

For T4 to convert to ACTIVE T3, the iodine atom of the OUTER ring is removed resulting in an active T3 hormone.

For T4 to convert to the INACTIVE hormone, Reverse T3, the INNER ring iodine molecule is removed.

So, T3 and Reverse T3 are mirrored versions of each other. One resulting in an ACTIVE hormone, one resulting in an INACTIVE hormone.

It is because Reverse T3 is INACTIVE, it is also considered to have no “significant” biological function and is often deemed irrelevant.

So, if it is irrelevant, then why am I telling you it may be the key to figuring out why your symptoms are so persistent?

A high Reverse T3 can result in all the hypothyroid symptoms you are familiar with even when other thyroid labs are normal (and it is almost never checked). Symptoms like:

• Fatigue
• Brain fog
• Low energy
• Chronic muscle pains
• All the other hypothyroid symptoms and complaints people suffer from when they are being told that their labs are “normal.”

For an extensive list, download this document: Common Signs and Symptoms of Hyper and Hypothyroidism

Labs vary in reference ranges:

• Typical lab range for Reverse T3 is referenced as: 8-25 pmol/L
• Optimal range for Reverse T3: 8-10 pmol/L
• There should be more than 10 times as much T3 (ACTIVE hormone) to Reverse T3 in the blood.

Here’s the answer as to why Reverse T3 matters:

Reverse T3 acts as a COMPETITOR to T3. Reverse T3 INHIBITS and BLOCKS the cellular receptor sites that are intended for T3.

This literally BLOCKS T3 from getting into the cell. So, even if you have PLENTY of T3 circulating in your blood (according to your lab values), it is still possible that the ACTIVE hormone, T3, is blocked from getting to its intended receptor site in the cell.

Think of it like this. If you fill up every day on doughnuts, ice cream, and chips; then you are simply TOO FULL to take in nutrients your body actually needs to fuel itself. You are FULL, but you are not FED (or receiving nutrients)!

Why does your body make Reverse T3? My dive into the research shows that Reverse T3 is a regulatory response or an “OFF SWITCH” the body can use to decrease the metabolism or CONSERVE ENERGY when the body is UNDER ATTACK!

A great way to think about these two hormones is this:

• T3 is the accelerator Reverse
• T3 is the brake.

If you have a high Reverse T3, then the goal is to figure out WHY your body is pumping out extra Reverse T3 so you can solve the problem so the body can heal.

Common reasons for this are:

• Fasting, calorie restriction, or malnutrition (don’t get me wrong, I am a big fan of fasting, but it is not right for everyone)
• Acute or chronic illness
• Injury
• Inflammation
• Chronic stress
• Low iron stores
• Cortisol deficiency or other hormone imbalances
• Insulin resistance or diabetes
• Pregnancy
• Chronic infections (that are often going undetected by the immune system)

What kinds of infections am I talking about?

• Parasites
• Bacteria
• Viruses
• Fungus
• Mold
• Other infections

We all have these infections. The question is not IF we have them, but how well is our body able to deal with them.

Isn’t the body brilliant?

The body is pumping out Reverse T3 to SLOW YOU DOWN in order to HELP you! By understanding that the body is trying to put the brakes on to help you, then you can use this information to support your body back to a state of homeostasis (balance).

What can you do?

• Provide high quality nutrition for your body, specifically high-quality protein and fats, but also healthy carbohydrates
• Do calming exercises like meditation, listening to calming music or light stretching
• Say “NO” to things that are stressing you out or extra activities
• Stop pushing yourself so hard
• Reduce exposure to environmental toxins, heavy metals, and infections
• Get quality sleep so the body can repair
• Remove the build up of environmental toxins, heavy metals, and infections

Once you remove the reasons your body has for putting the brakes on your metabolism and forcing you to rest, the body can start to restore itself and do the proper conversion to Active T3.

Often when people are diagnosed with hypothyroidism, they are put on the prescription medication called levothyroxine (brand name Synthroid). Levothyroxine is made of T4 only. This medication is an excellent option for many people struggling with low thyroid hormones because the T4 stores so well in the body, and the body can make the T3 when it is needed. However, it can be almost useless for someone who is unable to convert to T3 or someone who over-converts T4 to Reverse T3.

If a high Reverse T3 is your issue, then the ultimate goal is to figure out WHY your body is putting the brakes on your metabolism and support your body in what it needs to get better. By removing toxins, heavy metals, infections, parasites, and other assaults on the body, you can remove the barriers preventing your body from healing.

I hope you are as excited to start finding answers about your thyroid as I am to be helping you find those answers. I hope these thyroid puzzle pieces are beginning to come together for you.

I look forward to next week, where I will be teaching you about the lab test T3 Uptake, a.k.a. T3 Resin Uptake (T3RU) which gives insight into the availability of the hormone-binding proteins needed for T3 to bind to.

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