Thyroid Adventures—Part II---Functions and Disorders (and a tad bit on exercise…)

Now that you know what the thyroid hormones are and how they are transported about the body, now it’s time to dig a little deeper. This week’s article is about function, or purpose of thyroid hormone, and what can happen when there’s an imbalance.

The thyroid hormone performs and regulates so very many interrelated functions that it could be the poster child for the concept that body and mind are never separate.

In normal body function, the brain releases Thyroid Stimulating Hormone, or TSH. The thyroid, under normal circumstances, releases its own hormones that pack up, head out and do their good works around the body. Here are the chief actions that these hormones instigate and regulate...

1) Basal metabolic rate, or general body temperature.

2) Increasing the body’s sensitivity to catecholamines, one of which is adrenaline, by way of permissiveness.

3) Proper development and differentiation of body cells, acting as one of the chief growth hormones. This is why it is so important for newborns to get tested for hypothyroidism, because if there is too little hormone, a baby can’t grow correctly once it’s outside the mother. (Many factors can cause hypothyroidism in infants, but that’s another article entirely.)

4) Efficient regulation of protein, fat and carbohydrate metabolism, affecting how cells use energy compounds. Proper metabolism of vitamins is also an important thyroid hormone function.

As indicated in the first article, iodine is important for thyroid hormone synthesis, but, as I indicated in number 4 in the functions list, numerous pathological and physiological influences can affect hormone production.

These numerous influences (including TOO much iodine!) can lead to hormone imbalance. The most commonly known results of such imbalances in either extreme are...

1) Thyrotoxicosis, or Graves’ disease; the two most well-known symptoms of which are a goiter and racing heart. This happens when there is too much free T4, T3, or both. This affects 2% of women and 0.2% of men.

2) Hypothyrodism, the result of not enough thyroid hormone in the body. A variation on hypothyroidism is Hashimoto’s thyroiditis. One of the many notable symptoms of hypothyroidism is clinical depression. T3 has been found to be at the junctions of synapses, regulating the flow of feel-good chemicals serotonin, norepinephrine and Gamma-aminobutyric acid, or GABA. If there is not enough T3 present to keep the flow going, the activity of the feel-good chemicals diminishes, producing the onset of depression. Another obvious symptom is weight gain, resulting from inefficient regulation of metabolism.

An important note about the symptoms of hypothyroidism and how they can be managed by the hypothyroid person:

There is a vicious cycle between not-so-good mental health, diet and weight gain. It has been proven that when people exercise, they raise their metabolic rate, burn fat and increase endorphin levels. Eating beneficial foods also increases general well being on a mental and physical level. Easy enough to do when your thyroid functions normally, and you’re motivated by the properly regulated chemicals that keep you in a cheery disposition.

But if you’re hypothyroid, th