Currently 5-10% of the population is diagnosed with hypothyroidism, however some experts estimate that between 25-40% of the adult population has suboptimal thyroid function.
Thyroid hormones regulate the activity of mitochondria, the energy powerhouses, in every single cell in the body, therefore they have an effect on virtually all of our bodily functions. So when we have a deficiency of thyroid hormones, symptoms can be wide-ranging and non-specific having a detrimental effect on overall health and often being mistakenly diagnosed for something else.
Sub-optimal thyroid function could therefore be a factor in many more conditions than is currently realised, and should be considered particularly in patients who do not respond well to interventions for other conditions.
Symptoms of low thyroid function include but are not limited to:
- Difficulty losing weight
- Dry skin
- Lethargy or fatigue
- Memory problems
- Menstrual problems
- Recurrent infections
- Sensitivity to cold
- Thinning of head hair
- Voice changes
Thyroid hormone activity is tightly regulated. Firstly, the hypothalamus releases thyroid hormone releasing hormone (THRH), which stimulates the pituitary to release thyroid stimulating hormone (TSH).
TSH triggers the thyroid to produce T4 (thyroxine), a tyrosine molecule bound to 4 iodine molecules. About 20% of T4 is converted in cells into T3 (triiodothyronine, which is 4 times more potent than T4), by the removal of one iodine. Poor conversion may occur due to lack of co-factors or T4 may be converted to reverse T3; an inactive molecule still with a tyrosine and 3 iodine molecules but with a different structure to T3 and which can inhibit the action of T3. Any one or more of these pathways can be interrupted leading to hypothyroidism.
- Primary hypothyroidism – low T4 or T3 and high TSH (it can also be high T4 but low T3 because of poor conversion e.g. due to lack of cofactors such as selenium and zinc)
- Secondary hypothyroidism – low T4 and TSH, poor pituitary release
- Tertiary hypothyroidism – low production of THRH from hypothalamus
- Autoimmune – production of antibodies against the thyroid gland
- Wilson’s syndrome – normal levels of T4 and T3 but high levels of rT3
Hypothyroidism will be diagnosed with blood tests to measure TSH and T4, alongside specific symptoms. Occasionally T3 and rT3 will also be tested. Factors that lead to increased rT3 production include stress, dieting and low iron levels. It is thought to be a way for the body to reduce metabolic rate so as to conserve energy, as rT3 inhibits the action of T3.
It is quite common to have subclinical hypothyroidism, where no diagnosis will be made based on blood tests as results are within the normal range. However thyroid function is not optimal and therefore individuals can experience vague symptoms which are treated with weight loss diets, antidepressants, statin medications, IVF etc. whereas the actual problem is thyroid dysfunction.
Subclinical hypothyroidism can be consistent with the above symptoms as well as a low basal body temperature (temp below 36.5oC taken immediately upon waking, although this can also be affected by adrenal, immune and menstrual function) and the Achilles reflex test (slowed in hypothyroidism), as well as suboptimal blood results or auto-antibodies.
If you are diagnosed with hypothyroidism you will likely be prescribed thyroxine (artificial T4 thyroid hormone) which can help to alleviate many associated symptoms. However, this is if T4 can be adequately converted to T3 – if selenium or zinc are low then this conversion may not work well and people may remain symptomatic.
For people with subclinical hypothyroidism there is little medical support available. It is possible, however, to support thyroid hormone production with nutritional interventions.
Many nutrients can be used to support thyroid health but these are the ones which are directly involved in the production of thyroid hormones:
Tyrosine – An amino acid that is a major constituent of T4, should not be supplemented along with thyroid hormone replacement medications e.g. thyroxine unless under the supervision of a qualified medical practitioner.
Iodine – four iodine molecules are combined with tyrosine to produce T4, should not be supplemented along with thyroid hormone replacement medications unless under the supervision of a qualified medical practitioner.
Selenium – a cofactor for the enzyme which manufactures T4, and the enzyme which converts T4 into T3. Supplementation has also been shown to lower auto-antibodies to thyroid hormones.
Zinc and copper – cofactors for the conversion of T4 to T3.
A deficiency of any of these nutrients may lead to reduced levels of thyroid hormones.
Goitrogenic foods including soy and raw brassica vegetables (in large quantities) can bind to iodine, making it unavailable to the thyroid, thus inducing an iodine deficiency. Cooking inactivates this action therefore it is not necessary to avoid these foods but they should not be consumed raw in excess.
When we are under physical, psychological or environmental stress our adrenal glands release cortisol. High levels of cortisol can interfere with the conversion of T4 to T3, leading to a reduction in T3, and have been shown to increase rT3. Therefore, stress management and adrenal support is vital when supporting the thyroid. The adrenal glands should be supported both with diet and lifestyle.
Vitamins C, B5 and B6 support normal adrenal function and cortisol production.
Magnesium is considered a natural tranquiliser due to its function to relax both skeletal and smooth muscle. It is also an essential cofactor for many enzymes involved in the production of adrenal hormones and therefore is depleted in times of stress.
Phosphatidyl serine has inhibitory effects on HPA (stress) axis – it has been shown to lower cortisol levels.
Adaptogenic herbs, such as Ashwagandha, Siberian ginseng, Panex ginseng and Rhodiola, modulate the stress response.
Lifestyle – many lifestyle factors can help to reduce cortisol levels and calm the mind and body here are a few examples:
- Meditation or mindfulness
- Moderate, enjoyable exercise
Local conversion of T4 to T3 by the enzyme intestinal sulfatase in the gut is supported by healthy intestinal bacteria. Lipopolysaccharide (LPS) produced by dysbiotic bacteria inhibits this enzyme, again reducing T4 to T3 conversion. Therefore, in order to support conversion of T4 to T3 a healthy gut flora should be encouraged.
For example, by consuming prebiotic and fermented foods such as: chicory, apples, Jerusalem artichoke, dark green leafy vegetables, olives, plain yoghurt, kefir, raw sauerkraut and kimchi; and taking a live bacteria supplement, containing a wide variety of beneficial strains.
Hashimoto’s disease is a form of autoimmune hypothyroidism. Onset of Hashimotos’ disease has been associated with coeliac disease as well as non-coeliac gluten sensitivity. Gluten has been shown to cause local inflammation of the enterocytes which line the digestive tract.
Gliadin found in gluten can activate zonulin which has a negative effect on the permeability of the gut leading to damage and the progression of leaky gut. When this happens larger proteins, allergens and toxins are allowed into the blood stream. This can lead to systemic inflammation and triggers immune complexes, which have the potential to produce antibodies against proteins that are similar to our own body tissues, and therefore lead to autoimmune disease.
In order to help modulate autoimmunity the health of the gut should be considered as well as immune modulating nutrients:
- Remove gluten and casein which have been shown to have a detrimental effect on gastro-intestinal permeability
- Glutamine, found in bone broths or as a supplement, supports the repair of the gastro-intestinal lining
- Vitamin D3 – T helper 1 (Th1) is an essential part of the innate immune system, particularly in response to infection. However, the balance of Th1 cells with T helper 2 (Th2) cells needs to be tightly regulated. Excess Th1 compared with Th2 for prolonged periods of time, in the absence of acute infection, is known as Th1 dominance and is associated with tissue specific autoimmune diseases such as Hashimoto’s. Research has shown that D3 can reduce Th1 dominance.
- Reduce exposure to xenobiotics which have been shown to increase thyroid autoantibodies. See Cytoplan blog: Planning and implementing a detox for ways to reduce exposure and support detoxification.
Inflammation is at the heart of most chronic diseases particularly autoimmune diseases, the Western diet and lifestyle tends to promote inflammation. It is essential that inflammation is reduced as much as possible in all people including those with reduced thyroid function. Pro-inflammatory cytokines have been shown to depress levels of circulating T3 and may interfere with the HPT (hypothalamus-pituitary-thyroid) axis. The following can help to reduce inflammation:
- Reducing foods high in omega 6 – e.g. farmed meats, dairy products and vegetable oils (such as sunflower and corn oils).
- Increasing sources of omega 3 from e.g. oily fish and flax, chia seeds and/or a supplement containing EPA.
- Curcumin – found in turmeric, has been shown to inhibit Cox-2 enzymes which produce inflammatory prostaglandins.
- Obtaining good levels of vegetables (6-8 per day) including dark leafy greens high in anti-inflammatory phytonutrients and antioxidants.
T3 Receptor Binding
It has been shown in patients with hypothyroidism that the ability for T3 to bind to receptors in the mitochondria can be diminished. This can be due to genetic mutations but can also be affected by nutrient status:
Vitamin A regulates retinoic acid which interacts with thyroid receptors and may improve thyroid hormone activity.
EPA/DHA improves gene transcription in relation to thyroid receptor function.
Zinc is a cofactor for thyroid receptor production.
As with many if not all chronic conditions there is rarely one factor that leads to disease onset, therefore all of the above should be considered when optimising thyroid health. Thyroid health should always be considered in individuals with conditions associated with symptoms of low thyroid activity such as CFS, fibromyalgia, depression, weight gain, cognitive decline and sub-fertility but this list is not exhaustive.
For further information about supporting thyroid health, the effects of low thyroid function and support for those with thyroid conditions visit Thyroid UK website, www.thyroiduk.org.uk.
If you have any questions regarding the topics that have been raised, or any other health matters please do contact me (Amanda) by phone or email at any time.
[email protected], 01684 310099
Amanda Williams and the Cytoplan Editorial Team: Joseph Forsyth, Emma Williams, Simon Holdcroft, Clare Daley and Helen Drake
Related Cytoplan Products
Thyroid Support has been developed to offer a Wholefood base multi mineral supplement to support thyroid health. Thyroid support contains Kelp, L-Tyrosine plus active nutrients to help ensure optimum levels of naturally-occurring thyroid hormones.
Adrenal Support contains a combination of vitamins, minerals, herbs, nutrients and plant extracts that may help support healthy adrenal function especially during stressful periods. This includes optimum levels of beneficial Food State™ pantothenic acid (vitamin B5), liquorice, ginseng and iodine.
Cytoplan’s kelp supplement comes in gluten-free capsules and contains 3 species of wild bladderwrack (the type of seaweed). The kelp is not only an organically rich source of iodine but also naturally ‘nutrient dense’ containing a broad spectrum of minerals, trace elements, micro-nutrients and vitamins, prebiotics and carotenoids. These act as catalysts in the body and stimulate vital enzyme reactions.
Acidophilus Plus contains Lactobacillus Acidophilus and 8 further live native bacterial strains, plus a small amount of prebiotic. This blend of native bacterial strains is designed to have activity throughout the whole GI tract.
Those on thyroid medication should consult their doctor before taking these products.