When a person experiences hypothyroidism, meaning his thyroid hormone production has decreased to abnormally low levels (low T3 and/or T4) this results in his metabolism becoming slowed down. The resulting effects are signs and symptoms affecting every area of the body with the severity of them depending on how advanced the hypothyroidism is.
Major Causes of Hypothyroidism
Hypothyroidism can have causes that are “primary” (in the gland) or “secondary” (indirectly affecting the gland). The number one cause of hypothyroidism, worldwide is iodine deficiency which is due to the fact that third world countries (less industrialized) account for most of the world population and are areas where iodine is lacking in their diets. The thyroid gland depends on iodine for production of thyroid hormones. Part of this lack comes from their not having iodized salt as we do, who live in the more advanced countries of the world where iodized salt is more easily attainable.
Industrialized countries have “thyroid autoimmunity” as the most common cause of hypothyroidism. This would also be referred to as “autoimmune thyroiditis”, with most cases falling under the “Hashimoto’s thyroiditis” umbrella.
Thyroid removal surgeries or procedures, in which part of the thyroid gland is removed as treatment for hyperthyroidism (overactive) or to remove thyroid nodules or large goiters, can also result in the need following, to replace thyroid hormone levels that become low.
Other less-common causes of hypothyroidism include pregnancies and problems involving the major glands in the brain that regulate hormone production in the thyroid gland. These are the “hypothalamus” (sends TRH to the pituitary gland) and the “pituitary” (sends TSH to the thyroid, in response to TRH). These glands work in a continuous loop unless disrupted by tumors that can develop within them with hypothyroidism being the end result when the process is hindered, also called “Central Hypothyroidism”.
Hypothyroid Symptoms
A slowed metabolism from hypothyroidism can cause an array of symptoms. These include joint and muscle aches, depression, fatigue and low energy, dry skin, hair loss, constipation, weight gain, water retention, swelling in the body (edema), slowed heart rate and breathing, heavier menstrual cycles, elevated cholesterol, goiter and changes in appetite. Symptom severity varies depending on the progression of hypothyroidism.
Diagnosis
Most cases of hypothyroidism are diagnosed through blood testing. A doctor will order a thyroid panel that includes several tests or he will possibly order a single test. These tests will measure the T3 and/or T4 thyroid hormones levels and/or the TSH level (Thyroid Stimulating Hormone).
With hypothyroidism, the T3 and/or T4 levels will decrease to low levels, while the TSH will increase to a high level. This is due to TSH being the hormone as mentioned earlier, that stimulates hormone production in the thyroid gland and when the gland is not producing enough, the pituitary increases TSH to an abnormally high level. In some cases, TSH will be the test that detects hypothyroidism earlier than any other tests.
Less commonly used tests to detect hypothyroidism are the “Radioactive Iodine Scan” and the "Radioactive Iodine Uptake Test". The first mentioned scan is done by administering radioactive iodine to a patient and taking radiology camera images to see how evenly the thyroid gland is absorbing iodine. The second mentioned test does not involve imaging but is a measure of how much iodine is being absorbed by the thyroid gland.
If the thyroid gland fails to absorb an adequate amount of iodine, hypothyroidism may be diagnosed. These tests are more commonly used to determine causes of hyperthyroidism (overactive gland) when excessive amounts of iodine are absorbed and to detect thyroid nodules (tumors) when iodine is absorbed unevenly in the gland.
Treatment
The goal of treatment for hypothyroidism is to increase low levels of thyroid hormone via a dose of prescribed replacement hormone. Doctors often prescribe synthetic T4 hormone drugs but some do prescribe combinations of T4 and T3 that come in either synthetic or natural brands. There is ongoing controversy in regard to which type of replacement hormone works best but the importance of the hypothyroid therapy lies in how well it is monitored and optimized.
The goal is to accomplish best possible symptom relief for patients, with dose adjustments made to restore bodily metabolism to the best possible level. This is done by monitoring the dose via repeat blood tests at approximately 8-week intervals, to measure the TSH, T4 and T3 levels. Once the proper levels are reached, TSH may be the only repeat blood test that is needed, with retests repeated about 2 to 4 times yearly.
Jim Lowrance - James M. (Jim) Lowrance has authored over 100 book and ebook publications since year 2004.
