Thyroid Gland

A few days after birth, every infant who comes into the world in Canada gets a little pin prick in the heel and gives up a drop of blood for analysis to determine the level of thyroid hormone in its tiny body.

For such a simple test, the findings can be hugely significant. About one in every 4000 infants is born with abnormally low thyroid hormone, which if not corrected may lead to severe mental retardation and stunted growth.

Normal development of the brain and body is just one of a long list of functions performed by this hormone. It is a regulator, controlling body temperature and the speed of the metabolism. It promotes the breakdown of glucose and mobilizes fats for energy, helps synthesize protein and cholesterol, aids heart function and digestion – and on and on. Thyroid hormone affects almost every one of our trillion cells.

The source of this versatile substance is the thyroid gland, a butterfly-shaped organ low in the front of the neck. The hormone that it produces is rich in iodine, an essential bodily element. But either too much (hyperthyroidism) or two little of it (hypothyroidism) and we are in trouble.

Thyroid production is regulated by chemical signals from the brain, and these in turn can be put out of whack by many different factors, ranging from stress, genetics and diet to vitamin deficiencies and lack of exercise.

In our grandparents’ time, hypothyroidism was quite common because of a widespread shortage of iodine in the diet. Many people suffered from goiter, a swelling of the thyroid gland that could grow to a large and unsightly protrusion under the chin. The addition of iodine to table salt has made the condition a rarity, at least in the developed world.

But hypothyroidism is still with us. Symptoms include depression, difficulty losing weight, dry skin, headaches, fatigue, constipation, memory loss, menstrual problems, high cholesterol and sensitivity to cold, the latter a obvious consequence of a slowed metabolism.

The simplest treatment is to add iodine to the diet by increasing the intake of sea fish, sea weeds (dulse, nori) or iodized salt (in moderation). Thyroid hormone replacement therapy (Synthroid, Cytomel or dessicated thyroid from pig) will have the same effect. Zinc, copper,
selenium and vitamins A, B, C and E are conducive to hormone production, as are exercise and the avoidance of food allergies.

Hyperthyroidism, too much hormone, speeds up bodily systems, producing symptoms that may include rapid heart rate and palpitations; a “wired” nervous system setting off tremours and anxiety, and a digestive system that is trying to work too fast, resulting in weight loss and diarrhea.

Other symptoms are exophthalmos (protruding eyes), heat intolerance, irritability and insomnia.

Patients with hyperthyroidism need a hearty and balanced diet of whole foods to meet their high metabolic needs. Foods rich in iodine are to be avoided, while zinc, selenium, coenzyme Q10 and vitamins A, C and E are useful supplements for anyone suffering from this condition. All are antioxidants and help to control free radicals, which can damage the thyroid gland.

It is possible to live without a thyroid gland – many people do, most often as a result of thyroid cancer. (Radioactive iodine-l3l released by the Chernobyl nuclear meltdown caused widespread thyroid cancer in children.) But no one can live without thyroid hormone – which means a lifetime on hormone replacement therapy if the gland is removed.