The thyroid gland is one of the most complex endocrine glands in the human body. It is perhaps best known for its role in regulating metabolic rate, yet it does so much more. Thyroid hormones regulate heart rate, breathing, central and peripheral nervous systems, body temperature, body weight, muscle strength, menstrual cycles and more. It’s no wonder then that when this important gland starts to struggle, symptoms can be incredibly diverse and adverse effects soon start to multiply. Unfortunately, symptoms don’t always immediately scream ‘thyroid’ and conventional testing isn’t a failsafe way to establish a problem. Suboptimal thyroid function can therefore be difficult to identify and is typically underdiagnosed. Comprehensive thyroid tests that evaluate a broader range of markers can be a more effective way of assessing thyroid health and are an invaluable clinical tool.
Recently we were privileged to catch up with Kate Osborne, a member of the busy Clinician Education team at Genova Diagnostics (one of the UKs leading functional test providers). We chatted all things thyroid and are pleased to share with you, Kate’s extensive clinical insights.
1) Could you give us an overview of the thyroid testing options that you offer? What is Genova’s most frequently used thyroid test?
We always recommend that patients start with the most comprehensive test they can afford. Comprehensive tests provide patient and practitioner with the fullest picture to work with, taking out any guesswork and so enabling the very best treatment protocol for the patient. Our most frequently used thyroid test is Thyroid Plus. This is the most comprehensive assessment of thyroid function that we offer and provides a full picture of thyroid health status. This is a blood test that assesses a wide range of thyroid markers; Thyroid Stimulating Hormone (TSH), Total T4 (TT4), Free T4 (FT4), Free T3 (FT3), reverse T3 (rT3), Anti-Thyroglobulin Antibodies and Peroxidase Antibodies.
We also offer the Total Thyroid Screen which is exactly the same only it does not include reverse T3.
With regards to assessing thyroid hormones in urine, we offer the Urine Thyroid Hormones which assesses T3 and T4 in urine.
2) Many patients report ‘normal’ thyroid function following testing with their GP, yet are struggling with multiple symptoms that seem to relate to thyroid dysfunction. Why is this and what testing would you recommend to dig a bit deeper?
A GP will often only test Thyroid Stimulating Hormone (TSH) and Thyroxine (free T4). There are two main problems with this:
• The references ranges used are quite broad which means that a more subclinical issue may easily be missed. It’s important to remember that everyone is different and what is ‘normal’ for one person may not be ‘normal’ for the next.
• TSH and free T4 will give the clinician an idea of what is happening with central thyroid regulation, however these markers don’t give much indication of peripheral regulation (conversion of free T4 into active (T3) and inactive forms (reverse T3) which happens at a cellular level in target tissues) which is where many problems can occur.
We would recommend taking a more comprehensive look at the thyroid using a test such as Thyroid Plus, which includes TSH, total T4, free T4, free T3, anti TG antibodies and anti TPO antibodies to assess both central and peripheral thyroid function as well as thyroid auto-immunity.
3) What are the main differences between blood and urine thyroid testing?
We would always recommend starting with a blood assessment of the thyroid, however the urine thyroid test serves as a valuable tool for detecting those patients that are suffering from low grade hypothyroidism who might otherwise go undetected through standard blood tests. We would use the urine analysis as an adjunct to other indicators of thyroid function such as body temperature, symptomology and standard blood thyroid tests.
4) What do you recommend clinically to support a patient with thyroid antibodies?
We see a lot of raised antibodies on thyroid test results. When antibodies are raised then we are looking at Thyroid Autoimmunity in the form of sub-acute thyroiditis, Hashimoto’s Disease or Graves’ Disease. We need to remember that Hashimoto’s is not a thyroid disease, but is an immune disorder and the immune system needs to be addressed. Here we recommend implementing an autoimmune protocol including removal of gluten and gut healing. Selenium supplementation has been shown in some literature to reduce autoimmune antibodies. Emulsified vitamin D is also a powerful immune modulator. Autoimmune problems can often appear as clusters so we would also recommend further investigation for other autoimmune conditions such as coeliac disease.
5) Hyperthyroidism is sometimes considered more problematic to deal with than hypothyroidism. How commonly do you see this on test results and do you have any clinical pearls to pass on?
We don’t see hyperthyroidism as much on test results, so from our perspective it seems less common than hypothyroidism. In theory though, it could also be missed on standard tests so may be more prevalent than people think, especially subclinical cases. Thyroid Plus test would give a clinician valuable information and could help to indicate whether thyroid function is overactive. For example, antibodies can either block receptors, which would result in Hashimotos Disease (underactive), or stimulate receptors, which would result in Graves’ Disease (overactive). For hyperthyroidism, we recommend a diet high in calories to compensate for increased metabolism. Caffeine containing foods and other stimulants should be avoided. Iodine should not be supplemented as it can increase thyroid activity and its action is therefore unpredictable. We recommend looking at antioxidants: vitamin E, vitamin C, CoQ10, selenium and zinc.
6) What do you recommend when thyroid testing shows a patient has a problem converting T4 to T3?
There are many factors that decrease conversion of T4 to T3; these include stress, trauma, low-calorie diet, inflammation, toxins, infections and certain medications. Addressing these areas would be of primary importance when conversion is shown to be a problem. Zinc and selenium are key nutrients in this case too, as they are needed to support the 5’deiodinase enzyme, which is involved in the conversion from T4 to T3.
7) How soon would you recommend re-testing thyroid function to evaluate the usefulness of a support protocol?
We would usually recommend a follow up test anywhere from 3-6 months after starting a support protocol. It’s really important to track progress and we do see noticeable improvements in test results within this time frame, including a reduction in antibodies, which is always motivating for a patient to see.
8) Which tests do you commonly recommend alongside thyroid testing?
It usually makes sense to investigate adrenal function alongside thyroid function as these areas are so closely linked, particularly if the patient is exposed to long term or acute stress and has symptoms that may suggest impaired adrenal function. The adrenal glands have a huge impact on the thyroid and vice versa so it’s crucial to consider the health of both together. Stress inhibits the production of thyroid hormones and can decrease the conversion of T4 – T3.
9) What are your thoughts on heavy metal toxicity and thyroid testing?
We know that toxins such as mercury, cadmium and lead can have a disruptive effect on the production of thyroid hormones so if there’s no other obvious cause then it’s definitely worth considering this. A toxic metal analysis is useful in this case.
10) What resources do you have for practitioners wanting to learn more about thyroid testing?
Our clinician support team are happy to assist you when choosing thyroid tests or interpreting test results. We are currently putting together a webinar on Thyroid which should be available later this year.
11) Anything else you would like to add?
With thyroid health it’s important to think outside the box and fully consider all the potential factors that could be having an effect when it is out of balance. Consider whether your patient has high enough levels of nutrients to make thyroid hormones and to support the conversion enzymes too. These key nutrients include iron, iodine, tyrosine, zinc, selenium, vitamin D and B vitamins. Other factors getting in the way could be stress, trauma, infection and pesticides. Think about the water they are drinking too – fluoride is an antagonist to iodine so this could be having an effect? Are they swimming in pools with lots of chloride as this can affect thyroid function too? There’s a lot to consider, but the flip side is that there is also so much you can do to help support patients naturally when the thyroid is out of balance.
About Kate Osborne MSc, BSc, Dip BCNH
Kate received her Diploma in Nutritional Therapy from BCNH College, London in 2006 and her MSc in Person Centred Nutrition from CNELM, Wokingham in 2015. Kate also runs her own practice in Pimlico focusing on Gastrointestinal Health.
Kate Osborne joined the Medical Education team at Genova Diagnostics in May, 2016.