Genes & your thyroid: the missing piece

So, you’ve finally been diagnosed with a sluggish thyroid. Here in Britain, you will be put on levothyroxine, the standard treatment for hypothyroidism. With this little pill, everything will change, you think to yourself.

Fast forward 3 months. You’re still exhausted, your body temperature is cold to the touch, you’re depressed much of the time and you can’t seem to shift any weight no matter how much exercise you do. Your hair may be falling out and your nails brittle.

What happened?

So you go back to the doctor and explain that the meds are just not working. S/he looks sympathetically at you and hands you a slip for a blood test. A week later, you call in for your results because no one has called you. The nurse tells you they are ‘Normal - No Further Action Needed.’

In disbelief, you get an appointment with your doc and explain that the blood tests are definitely wrong, you’re overweight, brain fogged, moody - you just don’t feel right. This time they may say with less sympathy that your bloodwork is ‘perfect,’ that you’re worrying too much and probably just have too much on your plate due to children / work / getting old / lack of exercise (choose any).

Faulty Meds for Faulty Genes

In fact, you may well be genetically incapable or less capable of converting T4 into the T3 your body needs due to a small fault on the Deiodinase 2 Gene (DIO2) [1]. Because every cell in your body has receptors for T3 and not T4, this can be a serious problem, in particular, because it appears that both T3 and T4 have a significant role to play in the health of your brain [2] and heart [3]. Unfortunately, the NHS won’t test for this, however, you can test for it yourself for about £80 through Regenerus Labs.

Once you can prove to your NHS doctor that you do indeed have a faulty gene, you should be able to get combination synthetic T3 & T4 treatment prescribed.

Genetic Predisposition & Lifestyle Factors

Interestingly, your genes may also leave you at higher risk for both hypothyroidism and Hashimoto’s thyroiditis, an autoimmune disease where your body attacks and destroys your thyroid hormone to the point that it no longer exists or is significantly decreased in size and performance.

According to Dr Noel Rose, Director of the Johns Hopkins Autoimmune Disease Research Center in Baltimore, Maryland, certain Northern European populations, such as the Irish, appear to carry these genes [4]. Epigenetic factors can outweigh our genes, however, when our lifestyles are compromised by stress, overwork and poor diet, sleep and exercise, we could be setting ourselves up for Hashimoto’s.

T3 & T4: The End of the Story?

There is also some debate as to whether sythetic T3 and T4 are enough to rectify hypothyroidism. According to Dr Alan Christianson, a naturopathic doctor based in the US, another thyroid hormone, T2, which is produced from T3, is also important to your body’s metabolism [5]. For many British thyroid patients, the only way to gain access to a full spectrum of thyroid hormones will be by taking Natural Dessicated Thyroid (NDT) from a foreign pharmacy with a script from a foreign doctor or an obliging local one because NDT is not in the UK Physician’s Desk Reference. T2 can only be obtained in NDT as there is no synthetic equivalent.

In fact, NDT contains a spectrum of thyroid hormones from T0-T4 [6]. Scientists believe that only T3 and T4 are relevant, but as we have seen from Dr Christianson’s work, T2 may be important, and scientists may well discover that the other thyroid hormones have a role to play in human health and wellbeing too. For me personally, natural dessicated thyroid worked best. Equally, I know others who did better on synthetic. We are each bioindividual and so some n=1 experimentation is necessary.

Bottom line: if you’re not feeling well and your GP or specialist endocrinologist still does not believe you, find a new doctor who will work with you to find the right combination of synthetic T3/T4 or NDT that your body needs. Functional medicine doctors are your best bet in Britain, however, you may well need to travel to the Continent to get the treatment you deserve.

[1] http://press.endocrine.org/doi/pdf/10.1210/jc.2008-1301

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3978256/

[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4318631/

[4]https://irishamerica.com/2013/08/all-about-autoimmunity-ask-the-expert-dr-noel-rose/

[5] The Complete Idiot's Guide to Thyroid Disease: Clear Information on Causes; Dr. Alan Christianson, Hy Bender

[6] http://www.thyca.org/pap-fol/more/hormones/

Photo credit: Ryoji Iwata, Unsplash