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High FT3 with "normal" TSH/FT4

Can anyone tell me what the following test results could indicate:

TSH: 1.143 (0.46-4.98)

Free T4: 1.18 (0.60-1.70)

Free T3: 4.19 (2.50-3.90) HIGH

These results are for my 16 year old son. I asked to have him tested seeing as he has been not feeling well for a long time now. Also because I have Hashimoto's Disease and Celiac Disease and have read that this can be hereditary.

11 Replies

Thank you for your reply! I will do some research on thyroid hormone resistance.


When you say he does not feel well, what do you mean? Do you think he feels hypothyroid, hyperthyroid, or something else? I came across a youngish male on another board who also had FT3 above range; so high T3 is probably more likely with the young. BTW, are you aware that there are different "normal" ranges for different labs?

I would strongly suggest you have him checked for gluten intolerance with the TTG, Gliadin Antibody, and whatever other tests someone knowledgeable about celiac/gluten intolerance suggests. There are also stool tests available to diagnose celiac enteropathy. He should also be checked for Hashimoto's (TPO antibodies, TG antibodies).

If he is a typical teen, he is probably eating enough gluten to kill a horse!

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His symptoms are always tired, he is constantly with upper respitory infections, anxiety, weight gain but has always been overweight since he was little. He had mononucleosis/Epstein Bar virus 2 years ago and really has not been healthy since then. His Doctor did test him for Celiac disease and it came back negative. He has also been tested for Lyme disease and that was also negative. That is why I asked for his thyroid to be tested to see if that could be the problem. The Doctor told me since his TSH is "normal" he would not have an autoimmune disease.


"Normal" TSH is not a good indicator for very much. What test(s) did the doctor do for celiac? I would get him tested for thyroid autoimmunity anyway. Also, there are other types of autoimmunity that can be triggered by gluten. If the doctor did the HLA-DQ2 and HLA-DQ8 gene tests, that proves nothing; I am negative for both of those, but got enteropathy, Hashimoto's, and hypothyroidism anyway.

Hashimoto's has been known to cause thyroid "flares", where the patient can feel hyper, then feel hypo. I'm not saying that I definitely think he has Hashi's; you just have to remember that the doctor isn't the one who is feeling unwell, so he does not have an incentive to do a lot more testing in order to chase the problem down. Have you had any other testing done, e.g. CMP (Comprehensive Metabolic Profile)? Have you tested any of his key nutritionals? Since he had mono, have you considered taking him to a specialist for immune system analysis?


The Celiac tests where: Gliadin IGA AB Value is 3 (0-19 is negative); Gliadin IGG AB Value is 2 (0-19 is negative); t-Transglutaminase IGA - <2 (0-3 is negative); t-Transglutaminase tTg - 3 (0-5 is negative); Endomysial Antibody IGA - Negative; Immunoglobulin IGA - 140 (90-386)

Folate: Value is > 20 (0.5-20) HIGH

Magnesium is 1.9 (1.9-2.7)

Vitamin B12 is 453 (190-914)

Vitamin K1 is 0.33 (0.13-1.39)

Vitamin D is 34.79 (30-100) Sufficient range

Total cholesterol is 154 (0-200) but HDL is 28 (40-60) LOW

Glucose and A1C are good.

These are all the tests that my son has had.

I have not had a follow up yet with the doctor to go over all these results.


Seems pretty definitive that he does not have a gluten problem. How is his blood pressure, and does he sleep well? Short sleep can lower immunity and affect HDL. I'm assuming you already have him on a diet that is low-sugar, with high quality fats? I take a high-dose D3+K1+K2 supp, looks like he could use that plus extra Mg. It would be interesting to know what his albumin and total blood protein are, since the immune system does need a decent supply of amino acids.


I was also thinking that he may need higher dose of D3. He is taking 2000 IU daily at the moment. He does take a multivitamin but maybe extra Mg would also help. Thanks for your advice and responding to me.


D3 is a significant immunity booster. Definitely recommend an increase to 4000.

Does he understand that exercise makes many people feel better? Many people (myself included) have better blood sugar and lipid levels when they turn up their heartrate. If he isn't participating in school athletics, running his heartrate up to 70% of max (max is about 204 at his age) for 20 minutes 3 times per week, could help pull him out of the dumps. It is also an immunity booster.


BTW, did doctors treat him with antibiotics when he had mono? That can wreck the microbiome. I imagine you have heard that the gut is the biggest part of the immune system. Probiotics will rebuild his microbiome. I've been well now for almost 4 years, but still use a small cup of 12-strain kefir every night as insurance.

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No. He was not on antibiotic for mono but he has been on it more than I would like due to upper respitory infections. I do think I really have to increase the vitamin D and add a probiotic and see if this will boost his immune system. Glad you are feeling well. Just wondering if you have been feeling well because you are gluten free?


I went gluten free in 2003, and my TPO antibodies eventually dropped to zero. But it actually took another 9 years to recover full health because lifelong celiac had done so much damage, and the docs I saw had no experience in bringing a patient back from that level of damage (and esp. no experience with how long-term celiac pushes blood protein below normal range, and why the normal range is too broad anyway). However I have become very aware that there are many people who don't have lab test evidence that gluten is damaging their bodies, yet feel much better when they go gluten-free. Of course, gluten is not the *only* bad guy in the modern diet.


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