Hypothyroidism is becoming an all too common condition in women over thirty. Current figures show that around 1 in 50 women, and about 1 in 1,000 men develop hypothyroidism at some time in their life.
The most apparent symptoms are fatigue, weight gain and cold intolerance, which in most sufferers can be quite subtle at first and thus result in there being quite some time before suspecting that something may actually be wrong. Most women initially dismiss these symptoms as a consequence of their busy lives. In today’s society many are now juggling careers and raising families so it’s easy to see why the symptoms could be blamed on the lifestyle. Other symptoms include general aches, feeling cold , dry skin, lifeless thinning hair, forgetfulness, headaches and depression.
The Role and control of the thyroid hormones
The thyroid gland is located in the neck, just below the voice box and wrapped around the wind pipe. The main thyroid hormone is thyroxine (T4) and 90% is produced in this form. 10% is produced in the more active form of triiodothyronine (T3). The thyroid produces its hormones in response to stimulation from another hormone which comes from the pituitary gland in the brain, rather aptly named thyroid stimulating hormone or TSH for short.
The thyroid hormones are somewhat under-rated, as they are essential for normal cell function and ultimately control much of the energy production by cells. Most cells in the body are a target for T4 and if there is not enough, then the cells become rather sluggish in their activities and simply slow down.
Energy is required by cells to prevent fatigue, metabolise food products, create heat, provide normal brain function, and growth and repair of other cells and tissues. It stands to reason therefore that if there is not enough energy produced by the cells then the symptoms listed above will occur. When T4 reaches the cells and it is then converted to the more active T3 by losing an iodide molecule. T3 has much greater activity potential (around x10 more than T4)
Causes of hypothyroidism.
Autoimmune thyroiditis is the most common cause of hypothyroidism in the UK. Autoimmune means that antibodies from your immune system attack parts of your own body, rather than attacking foreign bodies such as bacteria or viruses, in this case antibodies destroy your thyroid gland cells. This prevents your thyroid gland from producing enough thyroid hormones. Iodine deficiency can be another cause.
Hypothyroidism can be diagnosed by monitoring the levels of TSH and thyroid hormones in your blood. A diagnosis of autoimmune hypothyroidism is usually confirmed by the presence of particular antibodies in your blood.
HYPOTHYROIDISM is confirmed when TSH levels are high and T4 levels are low. If they are the other way around then this can be indicative of HYPERTHYROIDISM.
Routine Thyroid function tests (TFTs) in the UK only screen for TSH and T4. T3 levels are not checked.
Most patients respond very well to T4 therapy when the correct dose is established. Around 10% of patients however do not respond to T4 alone. One possibility for this is that there may be a problem in converting the T4 to T3. In these cases, combination therapy of both T4 and T3 may be required. This problem is much more widely recognised in the US and less so in the UK. There is unfortunately still a general lack of awareness of this fact amongst GPs. I know this from personal experience. It took six months for me to convince my GP that I was not responding to T4 alone and that I may be one of the 10%. Eventually I saw another GP in the same practice and persuaded him to request a full screen of TFTs including T3. The results came back showing the T4 levels to be in the high normal range and T3 levels were below normal. My T4 dose was halved and I was prescribed T3. Three days after commencing treatment the tiredness and headaches disappeared!
Hypothryoidism is a debilitating condition to live with, but very simple to diagnose and treat. The symptoms of course can be indicative of many other conditions, but underactive thyroid is a very common one, so anyone with excessive fatigue, cold intolerance and or weight gain should make an appointment with their GP to discuss the possibility of a blood test so that an underactive thyroid can at least be ruled out.
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