How to Understand Hypothyroidism: Underactive Thyroid

The following 6 points help us to understand what it means to be hypothyroid, how it is diagnosed and how it is treated.

1. Hypothyroidism means Thyroid Hormone Levels are Low

When the amount of thyroid hormones drop to abnormally low levels, which are those that regulate metabolism in the body, hypothyroidism develops. The two major hormones released by the gland are the T4 (Thyroxine: containing 4 iodine molecules) and T3 (Triiodothyronine: containing 3 iodine molecules). In some hypothyroid cases only the T4 level decreases, while in others the T3 is the one that becomes low. Yet others see both hormones drop to inadequate levels simultaneously.

2. Hypothyroid Conditions cause a Slowed Metabolism

The metabolic rate of the body, is the speed at which it burns fuels for energy, such as glucose, fats and carbohydrates. Much of this is accomplished by the thyroid gland, which sends-out the hormones that were discussed in point "1.". When hypothyroidism develops, the metabolism slows down and rather than burning these fuels, it falls behind due to low thyroid hormones and these energy-producing substances will begin to be stored as fat in the body. In addition to weight-gain, people with hypothyroidism can also experience symptoms of fatigue, depression, constipation, feeling cold in warm temperatures and dry skin.

3. TSH Rises with Hypothyroidism

The pituitary gland in the brain, which stimulates the thyroid to produce proper levels of thyroid hormones via the regulating hormone called TSH (Thyroid Stimulating Hormone), will send out higher-than-normal amounts in attempt to correct low levels of T4 and/or T3. This results in blood levels of TSH being abnormally high and if lab tests are ran, the TSH is sometimes elevated, even in advance of the T4 or T3 becoming abnormally low.

4. Hypothyroidism can be Autoimmune in Nature

Once a doctor has diagnosed a patient as having an underactive thyroid gland, he or she will then usually attempt to find the cause of the hypothyroidism. For some patients, "autoimmunity" is found to be the cause, meaning antibodies from the immune system are mistakenly attacking the thyroid, as if it is an intruder (as it would with viruses, bacteria and allergens). This damages thyroid tissues over time, causing a lack of hormone-producing ability within it and is the most common cause of thyroid dysfunction in industrialized countries (i.e. Hashimoto's thyroiditis), requiring permanent treatment.

5. Other Causes of Hypothyroidism

Some patients have temporary types of hypothyroidism, that resolve on their own or that only require short-term treatment (i.e. following pregnancy, a viral respiratory illness, after treatment of certain heart conditions or cancers and iodine deficiency). Rarely, traumatic or chronically stressful events can cause a short-term hypothyroidism called "Low T3 Syndrome" (also referred to as Wilson's Temperature Syndrome) and this type will usually resolve with short-term treatment as well. The same is true of babies who are born hypothyroid (congenital hypothyroidism), which is found via "newborn screenings" blood tests.

Other hypothyroid patients will have problems within their pituitary glands that cause inadequate release of TSH to stimulate thyroid hormone production (i.e. Central Hypothyroidism), which requires permanent (lifelong) treatment. If hypothyroidism develops in the elderly, this will also require treatment for the remainder of their lives, as will cases in which part of the thyroid gland is missing or damaged, due to traumatic physical injury, long-term exposure to toxins or birth defects.

6. Hypothyroid Treatments

Cases of underactive thyroid glands are treated by doctors giving patients prescribed supplemented thyroid hormone doses (replacement therapy). If iodine deficiency is the cause, this essential element is what a patient needs via adequate supplementation until the thyroid dysfunction resolves. In cases of irreversible thyroid disease, damage or inadequacy, thyroid hormone therapy has no substitute.

The presence of hypothyroid conditions and their causes can only be diagnosed by medical doctors and proper medical testing (i.e. blood tests and/or thyroid imaging).

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