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    Reverse T3 ??
    DAVE0207 posted:
    Does anyone have any experience in testing for this?

    Maura12345 responded:
    The Reverse T3 test is rarely ordered. I?ve been posting here for four years, and I can?t recall a single person who has ever had the Reverse T3 test. Here?s what I can tell you---

    Hormones are regulatory chemicals formed in one part of the body that travel to a distant part of the body where they regulate the function of cell activity (speeding up or slowing down). The thyroid hormones are T4, two forms of T3 (T3 and Reverse T3), three forms of T2, and T1. The numbers stand for the number of iodine atoms in each hormone molecule. The thyroid releases mostly T4, a small amount of T3, and tiny amounts of T2 and T1.

    The T4 is released in abundance because it is a kind of mother hormone; it is directly active in certain tissues that need ?fresh? T4, but most of the T4 in our blood exists to be metabolized into various forms of T3, T2, and T1. When our body needs the most metabolically active thyroid hormone, enzymes knock an iodine atom off the T4 molecule and turn it into T3. About 85% of the body?s T3 needs are produced by this conversion process, which occurs mainly in the liver but also in the kidneys; once converted in the liver and kidneys, the active T3 re-enters the bloodstream for action in other body tissues.

    About 40% of the T4 released from the thyroid gland is converted into T3, about 40% is converted into Reverse T3 (rT3), and the remaining 20% is metabolized by other pathways. Some websites erroneously lead readers to believe that Reverse T3 is virtually a poison, but it?s as necessary for healthy metabolism as T3 (which is why healthy bodies produce those two hormones in equal amounts).

    T3 and rT3 are each broken down into three forms of the thyroid hormone T2; two of these are metabolically active, but not as metabolically active as T3; one of these active T2 isomers functions to increase resting metabolic rate in brown adipose tissue and suppresses TSH, and the other increases resting metabolic rate in muscles. The T2 hormones are themselves broken down into T1 and then into T0; these last stages of thyroid hormone metabolism function to clear excess thyroid hormone from the body and to recycle raw thyroid hormone ingredients (like iodine and tyrosine).

    In people with otherwise normal TSH and Free T4, the Free T3 level can drop for numerous reasons, and in many of them, a decrease in Free T3 is accompanied by an increase in Reverse T3. The following are common causes of decreased Free T3:

  • Dietary deficiencies of selenium and zinc

  • Low carbohydrate diets

  • Low protein diets

  • Low calorie diets

  • Anorexia, starvation, fasting

  • Chronic and acute illness/Surgery

  • Prolonged cold temperature exposure

  • Sedentary lifestyle

  • Initiation of exercise routine in an out-of-shape person

  • Physical and emotional stress (esp. when it causes an increase in plasma cortisol or epinephrine or causes other adrenocortical activity that lowers thyroidal production of T3 and/or inhibits extra-thyroidal T4 to T3 conversion)

  • Certain prescription drugs

  • RARE inherited enzymatic defects that affect thyroid hormone synthesis

  • Heavy chronic alcohol consumption

  • Aging

    Many of these are part of the body?s defense system. For instance, when people go on a low carbohydrate, protein, low calorie diet, their bodies react to the cutback and lower their metabolic rate to help them conserve energy; this is how humans historically stayed alive through periods of famine. The same thing happens when people become ill with a non-thyroidal illness, and their bodies? goal is to slow them down so that they can heal. In any situation in which the body has initiated a decrease in Free T3 as a protective, defensive measure designed to slow down the metabolic rate, the Reverse T3 level will rise.
    DAVE0207 responded:
    Thank you Maura. You explained it well. I will be looking into the RT3 with my endo and primary. It seems I have been feeling lousy after several months of greatness. Many examinations performed to find the root of the symptoms. Now we are looking into the Thyroid medication and many of my hormone levels including cortisol.

    I had surgery for my gall bladder in March and was somewhat under stress for a while. Since around late February and early March, I have been having unexplained musculoskeletal aches.

    I use to be very physically active and worked out regularly for the fisrt three months on the medicine. Now my body is intolerant to anything strenuous. The question reguarding cortisol levels, stress and reverse t3 came into discussion with my MD's

    Thanks Again Dave
    Maura12345 responded:
    Symptoms of low adrenal function are chronic fatigue that worsened as the day progresses, low stamina, reduced resistance to allergies and infections, cold intolerance, cravings for sugars and starches, low blood pressure, low body temperature, difficulty concentrating or working under pressure, decreased appetite, low blood sugar, depression, excessive need for sleep, and joint and muscle aches. Low adrenals may alter tissue sensitivity to thyroid hormone, so the replacement hormone doesn?t work as well as it should (although it will work to some degree).

    Ideally, adrenal insufficiency should be corrected before thyroid hormone treatment begins. However, the treatment for adrenal insufficiency is the hormone cortisol (prescription hydrocortisone), a drug with serious and nasty side effects, and few doctors will prescribe adrenal hormones unless the deficiency is advanced; moreover, too much cortisol inhibits T4 to T3 conversion (a process by which the thyroid prohormone T4 is converted into the metabolically active thyroid hormone T3), so it?s a catch-22 for hypos with low adrenals.

    One approach is to have adrenal function tested and if necessary, corrected medically prior to starting thyroid hormone (however, this is rarely done unless the adrenal problem is advanced enough to warrant adrenal hormone treatment). The other approach is to start thyroid hormone replacement and help your body heal itself through good nutrition with adequate protein and reduced carbohydrate intake, moderate exercise, stress reduction exercises, adequate sleep, avoidance of stimulants like caffeine, and time.

    The botanical licorice root might help for patients with cortisol levels that are low but not low enough to treat with cortisol supplementation (licorice root extract slows down cortisol metabolism so the body can make the most of a limited supply); however, this extract raises blood pressure, so it?s not a risk-free option.
    cford41526 responded:
    I recently had a patient that had a reverse t3 level performed.This test is useful in evaluating thyroid function and metabolism, and to is utilized to evaluate euthyroid patients with low T3 concentrations.

    Reverse T3 is virtually inactive having only 1% the activity of T3 and being a T3 antagonist binds to T3 receptors blocking the action of T3. Normal metabolism of T4 requires the production of the appropriate ratio, or balance, of T3 to rT3. If the proportion of rT3 dominates then it will antagonize T3 thus producing hypothyroid symptoms despite sufficient circulating levels of T4 and T3. Reverse T3 has the same molecular structure as T3 however its three dimensional arrangement (stereochemistry) of atoms is a mirror image of T3 and thus fits into the receptor upside down without causing a thyroid response and thus preventing or antagonizing the active T3 from binding to the receptor acting as a metabolic break. A Reverse T3 dominance or functional hypothyroidism is a condition that exhibits most hypothyroid symptoms although circulating levels of T3 and T4 are within normal test limits. The metabolism of T4 into rT3 is in excess when compared to T3 therefore it is a T4 metabolism malfunction rather than a regular thyroid deficiency. Periods of prolonged stress may cause an increase in cortisol levels such as when the adrenal glands respond to the stress. The high cortisol levels inhibit the conversion of T4 into T3 which results in reducing active T3 levels. The conversion of T4 is then shunted towards the production of the inactive reverse T3. This reverse T3 may persist even after the stress passes and cortisol levels have returned to normal as the reverse T3 itself may also inhibit the conversion of T4 to T3 thus perpetuating the production of the inactive reverse T3 isomer. There is some argument to this last point with some research indicating that the elevated rT3 is only temporary and not a permanent condition. The medical authorities officially do not accept reverse T3 dominance theory and thus many doctors will refuse to treat this condition. We have found prolonged elevated reverse T3 in many of our patients whom all respond well to T3 therapy.
    james12345678 responded:
    yes you can get tested by the fibromyalgia and fatigue centers go to there web site and they have a webanar that will answer all your questions and if not there ph # is 1 866 443-4276 hope you find what you need
    ladyluvbugs3 responded:
    So, if you have elevated rT3, what do you do to resolve the problem? Is there a medicine or vitamin/herb that you can take to fix the problem? I have all the symptoms of hypothyroid but my T3 and T4 levels and TSH are normal. My dtr keeps increasing my synthroid (up to 175 mcg daily) but my hair is still falling out, I am cold, dry skin, brittle nail, low energy, weight gain.....
    jannet55 responded:
    I am new to this site and this thread. In fact new to any web boards. This explanation of ReverseT3 is great. I actually understood it! I am 65 and have been active, healthy, energetic my whole life but since the year 2000 I have had every life stresser there is and have been under a blanket of stress. Last June there was a huge stresser with my daughter and since then my life seems to have stopped.It was like I reached a cliff and fell off. Impossible to get to sleep at night,,,gained 10 pounds almost instantly, quit exercising due to extreme fatigue, body temperature drop and seemed cold all the time, brain fog, depression,, you name it I felt it! I heard about thyroid problems because of prolonged stress and so I decided to go to a Naturalpath . My MD doctor here did normal thyroid tests and said I was "normal". Went to Naturalpath , and she had me do a Saliva test for Adrenal function. Long story,,,short... Cortisol overload all day long,,, T4 not convertiting to T3... I started taking something called "Cortisol Manager" (sleeping all night again) 5 mcg Cytomel, B-Complex , also Guggul Plus for lipid metabolism support. That has been since April,, Had new blood test 10 days ago and was told the thyroid was now in better balance,,, but the thyroid antibodies were a tad high, and my RT3 was high. The previous blood test did not include anything but TSH, T3 and T4 so with this new blood test we didn't have anything to compare it too. But I took my temperature this morning and it was 97 which is the first time it has been that high since I started taking my temp... 96 in the morning was low for me in general because through the years every now and again I would take it just to check it in the mornings and it has always been over 97 degrees.

    When I got my Naturalpathic's email this morning telling me that the RT3 levels had just come in and were high,,, I did get distressed because I didn't understand what that meant. We have no Naturalpaths in my town because we are isolated and have to fly on and off our island,,, hence the email... When I started searching and found this thread I was thrilled because this made me understand so much better. Hopefully it is true that this is only a temporary increase in these levels. Have you ever heard of heavy metal toxicity as a cause of this? She mentioned she was sending me a hair testing kit. Just hoping that I can get really better... Thanks so much for this great thread!
    marjaz responded:
    hi all,

    am from the netherlands and have been on armour thyroid for a few years now for hashimoto. i don't notice any improvements. my T3 levels are too low. i am looking into the cause of this and of course for the solution.

    does anybody have an idea? an advice?

    have been suffering from young age from different auto-immune illnesses and i have been for the last 20 years on prednisone 7,5 mg. my age is 58
    Nabur responded:
    To cford41526:

    I am 68 years old with hypothyroid & adrenal insufficiency and have been poorly treated for the past 5 years.

    I read your post with great interest, especially the last sentence: "We have found prolonged elevated reverse T3 in many of our patients whom all respond well to T3 therapy."

    Since you have patients, I assume you are a doctor. I'm also assuming that "prolonged elevated ReverseT3" levels correlate with a very low FT3 level. Is this correct?

    My FT3 level is at rock bottom. My lab test from June 5, 2009 shows it to be 217, and the reference range (Quest Diagnostics) is 230-420. My Ft3 falls lower with each thyroid test that is taken, no matter what type, amount, or combination of thyroid meds I've been on.

    For the first couple of years, before my FT3 got this low (217), it wasn't as bad, but it was still always at the "lowest" end of the reference range.

    Finally, after I learned more about T3 meds, I asked the Naturopath if I could try a tiny bit of Cytomel (T3). Without rhyme or reason, he refused. (He never refused ANY dose of Armour, however, with its T3). When I asked 'why not,' he stated that he just didn't think it was a good idea. When I pressed on, asking why he did not think it was not a good idea, he said, simply, "Because I don't think it is"--end of conversation

    Aside from my completely unresolved hypothyroidism, I have absolutely no other health probems which would contraindicate my being treated with Cytomel.

    Over these past 5 years I have been treated with Uniththroid, Synthroid, Armour & Synthroid, Synthroid, Naturethroid, Synthroid & Naturethroid, in this order and at various dosages, by 4 different doctors:, a General Practitioner, an Endocrinologist, an Internist, and a Naturopath. (I was not being treated by these 4 doctors at the same time; but, because I continued to fail, I had gone from one to the other, trying to find help.)

    Despite trying to educate myself to the best of my ability, I've continued to go downhill. Either my ability is GREATLY lacking, or nobody else knows anything about fixing "true" hypothyroidism either.

    Right now, I'm necessarily, on my own......I can no longer afford to pay for any more "good advice" from people who are supposed to know what they're doing, but who just continue telling me to raise my dosage of T4 meds--an option which has NEVER worked--while my FT3 level falls precipitously, causing me to become weaker with each passing day.

    I have stopped everything except my hydrocortisone for my adrenal insufficiency (level 4). For that, I take 20 mg hydrocortisone in divided doses thoughout the day.

    I am open to suggestions from anyone, anecdotal or otherwise--anyone who has any knowledge whatsoever regarding this low FT3 problem. I would especially love to hear from anyone who has had a similar problem and managed to resolve it.

    Although I have never had a Reverse T3 test, my guess is that a FT3 as low as mine would indicate that I have the Reverse T3 going on. The conundrum is 'how in the world does one reverse the reverse T3 process?!

    Now, I've become afraid of taking either a T3 "OR" a T4 med. According to some literature I've read, taking more T3, e.g., Armour or Cytomel, can actually ramp up the Reverse T3 even more, thereby causing the FT3 to lower even more. (This apPEARed to have happened when I was on Naturethroid (dessicated thyroid -T3/T4 med.) On the other hand, I have also read that too much T4, as in Synthroid, can do the same! My head!

    Good diet; 5 ft. 4 in. tall; normal weight,115#; now, uncomfortable 124#; cannot exercise--even a little exercise, & I wind up in the fetal position on safa for the next 2-3 days; have just about every hypo symptom in the book, except for being cold or having muscle and joint pain.

    Oh, yes, and my body in its "INFINITE wisdom," has seen fit to save the hair of both my eyebrows and naughty bits-Yipee.

    1smoothgal responded:
    cford41526- I too am hypo & adrenal failure. I take Armour, but had continuing problems-doc then gave me same dose hydrocort as you-problems & feelings of unwellness continued. Upcoming surgery (hernias & needle biopsy of breast) required me to stop the hydrocort. My bio-identical doc suggested I take 2 BioFlavinoid Caps(2 with each meal-3X per day) & 500mg vitamin C with each dose of the bioflavenoids. This is a frigging miracle: I felt so good taking these non prescriptions-After surgery, I decided to no longer take the hydrocort . I still take Armour, but feel it is time for blood tests & a lesser dose(slight shaky feeling is the clue).

    Bioflavinoids can be found at any health food store-I recommend the "NOW" brand. Taking the 2 supplements together gives adrenals a much needed rest & boosts your feelings of well being tremendously. This could be the reason you feel so unwell & continue to seek relief the docs don't know how to give.

    If you prefer, you can try "Adrenal Energy" by Crystal Star -info at


    "Metabolic Advantage" by Enzymatic-info

    Both are available at most health food stores.

    I had been using these-one or the other(not together in the same day ever-makes WAY too much jitteriness) up until the doc suggested the bioflavinoids & vit C. I much prefer the feeling of no jitters, energy levels good, weight stabalized.

    I am 5'3" /weigh approx 112-115lbs/age 51/full menopause from hysterectomy on 4/08--- taking bio-identical hormone replacement & Armour since July08

    I hope this info helps you-it is a simple cost effective alternative to feeling more well-give it a try.

    Good Luck & Good Health to you. Kim
    Schwartzi responded:
    I have been lucky enough to finally find a great thyroid doctor in Torrance, CA at the Holtorf Medical Group who knows about T3. After a year of taking increasing amounts of westhroid which is like armour, I wasn't getting better. Still gaining weight (40 pounds total), dragging through the day, no libido, all kinds of problems. I was desperate, so I found a new doctor. Now I've been on T3 for about 8 months and I'm finally getting close to my correct dose. We had to work our way up and finally for the first time in over 2 years my weight has started to go down. I lost 10 pounds almost instantly, I feel more energy. I'm seeing the light at the end of the tunnel. He monitors my rT3 with every blood test. He said when it fell below 100 ( i think that was the target) that I would start to feel a lot better, and he was right. I just reached that number and that's when things started to change for the better. I think RT3 is especially a problem in people who have ever dieted strictly because it is the mechanism that prevents humans from dying during a famine. If you are able to come to Torrance, these guys really know what they're doing.

    Good luck!
    chenrko420 responded:
    Doctors usually don't test for it and I'm not quite sure of why. I'm wondering if its the cost of it.

    Anyhow, reverse t3 is only needed when there is a conversion problem from t4 to t3. But even in this case, most of time, its because of low calorie dieting or carb restriction as studies have shown that the thyroid hormone can be normalized with ~130 carbohydrate intake and that free fatty acids (ketogenic diets) can impair conversion of t4 to t3 in the liver.
    Dandawurm responded:
    I was tested by my doc for the ratio of T3 to RT3. The reason is that individual measurements can indicate that all is well, when it is not!!...when the ratio of T3 to RT3 is calculated, it can expose a problem with too much RT3 production...RT3 will block the affects of T3 into your cells, thus nullifying energy into your is your bodies way of slowing itself down due to extreme/sustained stress or illness..

    My ratio was tested at 5.26 (142/27)..a healthy ratio should be > 19..I stopped taking T4 or Armour and now on 60mcg of T3...need to flush the RT3 and get back to normal..

    Find a natural medicine doc who understands this about the thyroid..recommend reading Stop the Thyroid Madness or check out their web site..this helped me tremendously..
    esserkathy responded:
    I've had thyroid problems almost all of my life. I was born w/ a goiter and had a goiterectomy at 2 days old. I was hypothyroid until my teens when the doctor took me off of meds. After my daughter was born 8 years later, I never felt as energetic. I asked for a "complete" thyroid test, but I was always told it was within the normal range.

    3 years ago, I had a partial hysterctomy, and I started getting hot flashes recently. I went to a highly recommended doctor. I found out that I was in menopause, and at the same time, RT3 was found as well.

    I am on hormones for the menopause, and the hot flashes have disappeared. I also am taking Liothyronine: 12 1/2 milligrams for 2 weeks ...... next week the dosage will be 25 mg. I felt a burst of energy last week -- and I am looking forward to the increase next week when I start taking 25 mg.

    I've been told for years that nothing is wrong with my thyroid, but I knew something wasn't right. I was a 120 pounder ......... and over the years, I made it up to 175. I felt like I could look at food and gain 10 pounds. I worked out at the gym, and that didn't help. I wasn't accepting what I had others say before -- "well, you're old and you're metabolism isn't there anymore ...... and there's nothing you can do about it."

    I'm ready to become "me" again.

    Any advice is appreciated.

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