What should I know about Hypothyroidism?

Surrounding the windpipe just beneath the voice box, the thyroid gland is a small organ with a powerful influence on the body. The thyroid secretes hormones that affect virtually every organ. Thyroid hormones are required for growth and development in children. In adults, the thyroid’s main assignment is to regulate the production of metabolic energy. (1) The thyroid governs our "basal metabolism," which turns calories into useable heat energy. When thyroid hormone output is low, people are often tired, cold, and sluggish. They may also be overweight. Without enough thyroid hormone to keep metabolism humming along as it should, we simply do not function very well, physically or mentally. Hypothyroidism is a complex condition that manifests as a constellation of signs and symptoms caused by low thyroid hormone levels in the body.

The thyroid gland’s hormone-producing activity is controlled by the hypothalamus and pituitary glands in the brain. These glands can sense when the amount of thyroid hormone in the blood is low or high and give feedback to the thyroid accordingly. When thyroid hormone levels drop, the pituitary gland, upon a signal from the hypothalamus, tells the thyroid to make more. The pituitary does this by secreting a hormone of its own called TSH, or "thyroid-stimulating hormone." As the thyroid hormone level rises, the pituitary gland tells the thyroid gland to shut production down. This circle of communication between glands, called a "feedback loop," is designed to keep the amount of thyroid hormone circulating in the blood within a fairly narrow range, so we never have too much or too little. In hypothyroidism, TSH levels are generally higher than normal because the pituitary pumps out more TSH in response to low thyroid hormone levels.

Using iodine and the amino acid tyrosine as building material, the thyroid makes two hormones: thyroxine (T4), which has four iodine molecules in its chemical structure, and triiodothyronine (T3), containing three.

Hypothyroidism occurs in 1.5 to 2 percent of women and just 0.2 percent of men. The elderly are more prone to it. (2) , (3) , (4) The vast majority of hypothyroid people have primary hypothyroidism, where the problem lies in the thyroid’s inability to manufacture enough thyroxine to meet the body’s needs. Sometimes the pituitary fails to secrete sufficient TSH; this is "secondary hypothyroidism." The body may resist the influence of thyroid hormones, although this is rare.

Hypothyroidism makes one feel like an engine missing a spark plug. The mind and body are sluggish. Digestion is poor, cardiovascular function and mental activity slow down, and muscles weaken. (5) Low basal metabolism causes low body temperature, leaving the hypothyroid individual feeling chilly, with cold hand and feet, most of the time. The old saying, "My get up and go got up and went," aptly describes the person with hypothyroidism.


World Health Organization, 2001.

  • Permanent sporadic congenital hypothyroidism, with extremely elevated neonatal TSH, occurs in approximately 1 of 4,000 births in iodine-sufficient countries.

Malaysian Consensus, 2000.

  • Incidence of congenital hypothyroidism in newborn infants is between 1:4000 to 1:5000 in Malaysia. 

American Medical Women’s Association, 1999.

    Hypothyroidism affects approximately 11 million Americans.

The Thyroid Society, 1996.

    Hypothyroidism is 10 times more common in women then men. 1 out of 5 women over the age 75 has Hashimoto’s thyroiditis, the most common cause of hypothyroidism. 1 out of 4000 babies are born without a working thyroid gland.

Thyroid Federation International, 1998.

    By the age of 65, 17% of women have an underactive thyroid compared to 9% of men. 1 in every 4 babies is born with hypothyroidism.

Signs and Symptoms

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Common symptoms of hypothyroidism includes dry skin, cold intolerance, weight gain, constipation, and weakness. Less specific complaints include lethargy and fatigue, or loss of ambition and energy. Depression may result from untreated hypothyroidism. Coarse skin and hair, cold skin, puffiness around the eyes, and a slowed heart rate are also often experienced. Speech is often slow and may be hoarse. Muscle cramps, stiffness, and pain are frequent complaints. Your healthcare professional may want to check thyroid hormone levels.

  • Dry skin, cold intolerance, weight gain, constipation, and weakness
  • Less specific complaints include lethargy and fatigue, or loss of ambition and energy
  • Depression may result from untreated hypothyroidism
  • Coarse skin and hair, cold skin, puffiness around the eyes, and slowed heart rate
  • Speech is often slow and may be hoarse
  • Muscle cramps, stiffness, and pain are frequent complaints

Treatment Options


Therapy for hypothyroidism has two goals: 1) Relieving the symptoms caused by low thyroid hormone output and 2) Raising the blood level of thyroxine back up to normal. Synthetic thyroid hormone, which commonly goes by the names "synthroid" and "levothyroxine," is generally usually prescribed to replace the missing thyroxine. (6) Dessicated thyroid glandular tissue--once widely prescribed by doctors--is still available, but only by prescription. Although dessicated thyroid has been successfully used as a treatment for low thyroid, most doctors now prefer synthetic thyroid hormone because it allows for a precise thyroxine dosage.

Note: FDA regulations prohibit over-the-counter thyroid glandular products from containing thyroxine. The hormone must be removed from thyroid glandular tissue before it can be sold as a dietary supplement.

Nutritional Suplementation


Iodine is an essential mineral the thyroid requires to produce thyroxine. Severe iodine deficiency, still a problem in many areas of the world, causes the thyroid to enlarge. This condition is called "goiter." Before the iodized salt became available, parts of the midwestern U.S. with iodine poor soil were known as the "Goiter Belt." Iodine supplements may support thyroid hormone production. (7) , (8)


The essential trace mineral selenium works as a co-factor for various enzymes in the body. One of these is an enzyme that converts thyroxine (T4) into T3. A low dietary selenium intake may create a hypothyroid-like condition due to impaired conversion of T4 to T3. (9) Low levels of selenium may accelerate the depletion of iodine from the thyroid gland. Selenium deficiency may worsen some of the problems caused by a lack of iodine. Selenium deficiency may also be involved in the occurrence and development of some iodine deficiency disorders. (10)

People who are deficient in both iodine and selenium should not take selenium alone, as selenium may activate an enzyme that breaks down thyroxine. Taking selenium without iodine could make hypothyroidism worse for these individuals. If you think you may have low thyroid, have you doctor test for iodine deficiency before taking a selenium supplement. (11)

Herbal Suplementation


Bladderwrack is a highly nutritious seaweed. This marine plant is dried as soon as possible after collection for use as dietary supplements. A rich source of iodine, bladderwrack has been traditionally used for obesity and hypothyroidism. (12) , (13) The low incidence of goiter in maritime people has been attributed to the iodine in bladderwrack. (14) Bladderwrack also contains potassium, magnesium, calcium, iron, zinc, and other minerals. (15) Bladderwrack is thought to stimulate the thyroid gland, thus increasing basal metabolism.

One note of caution: Overdosages of iodine may lead to symptoms of hyperthyroidism, including weight loss, fatigue, and frequent soft stools. These symptoms were reported in a 72 year old female after six months of taking a commercial seaweed product. (16) Another report of a 24 year old woman developing thyroid goiter after taking a proprietary product containing 0.4-0.5mg/day of iodine for three months. (17) To avoid potential iodine toxicity problems, use seaweed supplements that list the iodine content on the label.


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