The thyroid is critical to the proper functioning of your metabolism. In fact, there are only three major hormones that control your metabolism. They are the thyroid hormone, insulin and cortisol. One of the most commonly-diagnosed problems with thyroids is an underactive thyroid. An underactive thyroid is called hypothyroidism. This condition can lead to weight gain, but it also comes with other negative symptoms that detract from the quality of life. Symptoms of Hypothyroidism The symptoms of hypothyroidism may include: ● Loss of muscle strength● Dry skin● Constipation● Puffy eyes/face● Chronic fatigue● Memory loss● Ultra-sensitivity to cold● Hoarseness● Thinning hair● Depression Note
Hypothyroid is also known as low or underactive thyroid. This condition occurs when the gland fails to produce proper amounts of the thyroid hormones (T3 and T4) to meet the body’s needs. Thyroid disease is estimated to affect 200 million people worldwide, with recent studies showing that as many as 1 in 10 Canadians are affected. Of those affected with thyroid dysfunction the majority are women, of which an estimated 50% remain undiagnosed.
There are numerous factors that may contribute to low thyroid function including:
- Autoimmune disease
(known as Hashimoto’s thyroiditis)
- Hyperthyroid treatment (using radioactive iodine or thyroid suppressing medications)
- Thyroid surgery
- Radiation therapy of the head and neck regions
- Medications such as birth control, hormone replacement, and antidepressants
- Iodine deficiency
- Pituitary tumor
- Congenital defects
In addition to the many contributing factors for hypothyroid, the list of potential symptoms is also numerous. Please see Table 1. Symptoms and Disorders Associated With Hypothyroidism.
Conventional testing for hypothyroid involves a blood test that primarily investigates TSH (thyroid stimulating hormone). If this measurement is elevated (>5.5
Six Patterns of Hypothyroid toConsider
Pituitary dysfunction – caused by chronic stress during which high levels of cortisol1 are secreted, pregnancy, low blood sugar or insulin resistance. These stressors tax the pituitary so it no longer signals the thyroid to
Elevated TBG – TBG (thyroid binding globulin) is the protein transporter for thyroid hormone. When thyroid hormone is bound to TBG, it is inactive and unavailable to the tissues. Elevated TBG can be caused by high estrogen levels (from estrogen-containing birth control pills, or hormone replacement therapy). Thus, with high TBG, levels of unbound thyroid hormone will be low, leading to hypothyroid symptoms.4 With this pattern, TSH and T4 will be normal. T3 if tested will be low and TBG will be high.
Decreased TBG – the reverse of above. When TBG levels are low, free thyroid levels are high. Intuitively you would think this would cause high thyroid function,
Thyroid resistance – in this pattern both the thyroid and pituitary are functioning, but the hormones
Hashimoto’s thyroiditis – an autoimmune disease where the immune system develops antibodies that then attack thyroid tissue. Potential causes
This means that with respect to laboratory testing, your values are within range. However, your clinical history and physical symptoms may all point to hypothyroid; therefore a course of thyroid treatment should still be considered.
Basal Body Temperature
Patients with suspected hypothyroidism that have normal lab values may get additional information about their condition by measuring basal body temperature. This test is performed by placing a thermometer deep in the armpit for 10 minutes, immediately upon waking and before getting out of bed. Typically the temperatures are taken over 5 days and the results are averaged. Women should begin taking their temperature on the second day of menstruation, which is the time in the cycle when the body temperature is the lowest. If the temperature averages below 36• C, then this could be a clue that a hypothyroid condition is possible. Basal body temperature is an estimate of basal metabolic rate, which is intimately linked to thyroid function.
Conventional treatment for hypothyroid is almost unanimously levothyroxine (
Tyrosine: An amino acid that when combined with iodine, makes thyroid hormone. It is interesting to note that tyrosine is also the building block for the stress hormones epinephrine and norepinephrine. Thus, when under stress, thyroid production can be reduced, as
Coleus Forskohlii: The Ayurvedic herb Coleus forskohlii, and its active
constituent forskolin, can raise the production and release of thyroid hormones in animal and in-vitro studies.8
Bacopa monnieri: Studies in male mice showed that Bacopa possesses benefical thyroid-stimulating effects, increasing T4 concentration by 41% after supplementation for 15 days when compared to non-treated mice.9
Copper: Copper plays an important role in thyroid metabolism, especially in hormone production and absorption. Copper stimulates the production of the thyroxine hormone (T4), and prevents over-absorption of T4 in the blood cells by controlling calcium levels in the body.
Zinc: Zinc plays
Selenium: Is essential for normal thyroid hormone metabolism, it is a cofactor for various iodothyronine deiodinases (enzymes) that control the synthesis and degradation of the biologically active thyroid hormone, T3.10 Thyroid health is a key ingredient to managing energy, weight, aging, and overall well-being. Low thyroid function can be something that may fly under the radar ofregular medical checkups, ormay be tested and deemed fine by laboratory standards. This article has attempted to highlight that this screening is not always sufficient, and your physical and emotional symptoms should be taken into account with equal consideration as there may be other factors at play.
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