Your thyroid is a gland situated in the front of your neck. The hormones (chemical messengers) that it produces affect a great number of your body processes and other glands. So if your thyroid becomes underactive (medical name hypothyroidism), your whole body is thrown off balance.
Official estimates of hypothyroidism in Western populations vary from two to seven per cent, although some experts believe it is significantly under-diagnosed, and that the true percentage is probably as high as thirty per cent. Whatever the case, hypothyroidism appears to be increasing and this is starting to attract the attention of researchers, clinicians and government health departments as an emerging public health problem.
So how do you tell if you might have an underactive thyroid? Lack of energy, weight gain, dry, pale skin, feeling cold all the time and depression are the most well known symptoms. But low thyroid can cause a surprisingly wide variety of symptoms, which can be totally different from individual to individual. Many of the symptoms are also symptoms of other conditions. For these reasons, and because physicians are generally unaware that hypothyroidism is so common, hypothyroidism is a frequently missed diagnosis.
An example of this is the person who complains of putting on weight unexpectedly or being unable to lose weight despite a modest calorie intake. Such a person is almost automatically assumed to be overeating and told to reduce calorie intake. Even if they ask whether it could be their thyroid, they are unlikely to be tested.
Or take depression. What thyroid expert Dr Barry Durrant-Peatfield says is quite shocking: "Any patient suffering from depression should be routinely assessed for hypothyroidism. There should be no exceptions; half to one third will be found to be hypothyroid, and as a result of treatment, their depression will begin to lift in weeks." How many people are being treated for depression with medications or psychiatric counseling, when in actual fact they just need their thyroid fixed?
Yet another example is high cholesterol. Studies show that more than ten per cent of people with high cholesterol have hypothyroidism, but unfortunately most people with high cholesterol are not tested for this. That's a lot of people who are taking cholesterol-lowering drugs needlessly.
CFS (Chronic Fatigue Syndrome) or ME is another condition which experts believe is in many cases actually misdiagnosed hypothyroidism. Low fertility and repeated miscarriages is another. Other problems that can be caused by hypothyroidism include:
- brittle nails, hair loss, boils and spots, eczema and psoriasis, hoarse voice, slow speech
- constipation and haemorrhoids, painful irregular periods
- muscle weakness, muscle and joint pain and stiffness, shooting pains in hands and feet, carpal tunnel syndrome
- gallstones, visual disturbances, breathlessness, halitosis, candida (intestinal yeast overgrowth)
- impotence, loss of libido, bladder irritation and frequency
- deafness and tinnitus (ringing in the ears), ankle swelling, palpitations, anxiety and panic attacks
- ADHD (Attention Deficit Hyperactivity Disorder), poor memory, poor concentration and slow thinking
Even if hypothyroidism is considered as a possible diagnosis by the physician, the problem doesn't end there. Thyroid tests fail to pick up many cases - the current 'normal' ranges for thyroid test results are quite wide, and thought by many thyroid experts to be wrong. Sanford Siegal, DO, MD, a US thyroid specialist, believes that about ten per cent of the population is hypothyroid but that maybe only half test positive with the blood tests that are currently used.
Dr Siegal's experience with patients who test negative but have clinical symptoms of hypothyroidism is that there is often marked improvement when thyroid supplementation is given. His experience has led him to believe that around a quarter of those who have difficulty in losing weight fall into this category and benefit from thyroid treatment.
The test at the centre of the thyroid testing controversy is the TSH. This test measures the amount of Thyroid Stimulating Hormone your pituitary gland releases. If it is high, it means your thyroid hormone production is low and the pituitary is sending repeated chemical signals to try to get your thyroid to produce more thyroxine. So a high TSH means you are low thyroid.
In the TSH test, the upper limit of 'normal' may be given as anything from 3 µU/ml to 6 µU/ml depending on which country you live in and which lab has done the test. However, Dr Barry Durrant-Peatfield, in common with many other thyroid experts, regards even the recently revised limit in the US for 'normal' TSH levels of 3.0 µU/ml as too high. His experience with patients has led him to believe that a level of 2.0 µU/ml should arouse suspicion, and anything over 2.5 µU/ml should be diagnostic and therefore treated as hypothyroidism.
So if you have some of the symptoms in the list above, and particularly if you are having difficulty in losing weight, ask your physician to test you for low thyroid. Be aware of the issues surrounding current methods of testing and make sure you get copies of the actual test results so that you can compare them with the reference ranges used by those thyroid specialists who believe the current 'normal' ranges are too wide.
Similarly, if you have been tested in the past and told the results were normal, get tested again and ask for the actual values. If the TSH is above 2.5 µU/ml, bring the new ranges to your physician's attention and ask for a trial of thyroid hormone replacement.
Unfortunately, agreement of your physician to treat you for hypothyroidism is not the end of the story. There is also controversy over medication and dosage. The 'alternative' thyroid experts feel that patients are not best served by the usual treatment (consisting of replacement of thyroxine - called T4 for short). This is not the only hormone that a healthy thyroid secretes, and they believe that many hypothyroid patients fail to achieve 100 per cent improvement without the other hormones. The reluctance to prescribe better alternatives appears to be down to a mixture of historical practice, mainstream doctors' reliance on the drug companies who make the synthetic T4 preparations for information about treatment options, and a lack of research interest in the subject.
Dosage is a further area of controversy. Complex feedback loops that govern the workings of your thyroid mean that it is actually possible to make a patient worse by giving too small a dose of thyroxine. Many physicians are also constrained in their prescribing by blood test results and the official reference ranges for 'normal', rather than by their patient's clinical symptoms. Some hypothyroid patients fail to improve until their TSH falls to 0.3 or lower, but most mainstream physicians are reluctant to let it drop to even to that level.
It seems therefore that hypothyroids have had a raw deal for a long time. Happily, word is starting to spread amongst thyroid patients that a better quality of life is possible, and patients are starting to become indignant and vociferous in their demands for better diagnosis and better treatment. An indication of this is the recent proliferation of thyroid patients' websites, providing information about alternative treatments and helping fellow patients to locate physicians experienced in using them. Helpful sites include 'Stop the Thyroid Madness' and 'Thyroid Patient Advocacy'.
Although the cause of the increase in hypothyroidism is unknown, there is an interesting theory. This relates to iodine, which is critical for a healthy thyroid. Hypothyroidism is widespread in upland areas of the world which are far from the sea where food is grown on iodine-poor soils. Many countries have a national salt iodization program to combat this problem. Ironically, this may be having the opposite effect in some cases. The trouble is that too much iodine is just as harmful to the thyroid as too little. And it is possible that people who consume a lot of fast food, canned or prepackaged foods or eat in restaurants regularly could easily be consuming between 8 and 10 grams of iodized salt per day. This would provide more than four times the recommended daily allowance of iodine. Could this be a contributing factor to the increasing rate of hypothyroidism in Western populations, and in turn, to the increasing rates of obesity?
More information on how undiagnosed or undertreated low thyroid may make losing weight difficult can be found in the e-book "Why Can't I Lose Weight - The Real Reasons Diets Fail And What To Do About It".
Copyright DietPlateau.com and GoodDietGoodHealth.com 2007