tired?

Tired? Check your thyroid

Your Health
DR GITA MATHAI

Body temperature and weight, heart rate, skin texture, muscle and bone function, reproduction, bowel movements, sleep patterns and mental acuity are all controlled by a master computer in the brain — the pituitary gland, which sends its signals to a small gland in the neck called the thyroid. The 10-30gm gland cannot be felt by hand and its presence is unnoticed until it begins to malfunction.

One out of 4,000 children is born either without the thyroid or with one which functions sub optimally. Within a few months, parents notice that the child fails to grow as fast as his or her peers, does not feed satisfactorily, becomes constipated, has dry skin and a tongue that protrudes like that of a lizard. What is worse, mental development too is slower.

It is essential that the symptoms are recognised early on and a correct diagnosis reached because if such children do not get early and appropriate treatment they suffer physical and mental retardation.

In fact, thyroid problems can be diagnosed at birth by testing the cord blood TSH (thyroid stimulating hormone) level. This is routinely done in many hospitals. If the value is higher than normal (more than 20), the child is evaluated and treatment with thyroid hormones is started in time.

In adults, a thyroid that has been functioning normally can start malfunctioning (usually a drop in the production of thyroid hormones). This problem affects about 100 million Indians. The average age of such patients is 50 years, a majority of whom are women.

The initial symptoms are so vague that they are easy to miss — a tendency to put on weight, periods being heavier than normal, skin becoming dry, nails and hair brittle, constipation, muscle aches, lethargy and depression.

Such symptoms are often ignored and untreated. A feeling of “being tired all the time” is easy to dismiss. These symptoms can be mistaken for a normal part of perimenopause or depression or “the empty nest” syndrome. Patients may unsuccessfully try to counter the problems with nutritional supplements and multivitamin capsules. As the symptoms progress, the gland gets over-stimulated by the pituitary in an attempt to produce the required amount of hormone. It responds by increasing in size. A swelling called a goitre may then appear in the front of the neck.

At an advanced stage, the disease can be potentially fatal. As the symptoms progress, body temperature eventually drops, breathing decreases and depression and inactivity set in. The person may cease to respond, slip into a coma and die.

The body requires iodine to manufacture thyroid hormones. Adults require 150 micrograms of iodine a day. Pregnant and lactating women require 200 micrograms. Since the body cannot store iodine, it has to be taken every day. This iodine comes directly or indirectly from plants, fish and seaweed. Sea water does not contain sufficient iodine.

The amount of iodine obtained from the diet is insufficient in most cases. The government has asked salt manufacturers to fortify salt with iodine. Usually 30gm is added per kilo. Although the potency decreases with moisture, storage and cooking, usually 10-15gm of salt is consumed every day, and this provides most people with sufficient iodine.

Iodine deficiency is not the only cause of thyroid malfunction. The gland may be absent since birth, removed during surgery or destroyed by radiation. Some medications like lithium may interfere with hormone production. Stimulation of the gland may be insufficient because of pituitary disease.

The only way to treat thyroid hormone deficiency is through replacement therapy. The tablet has to be taken every day on an empty stomach first thing in the morning, otherwise it is not absorbed. The dosage has to be titrated for each patient as the response varies. Tablets should not be discontinued without a doctor’s advice. Usually, patients have to keep taking the pills all their life.

Thyroid hormones increase the BMR (basal metabolic rate). The heart rate increases, there is sweating, fine tremors and weight loss. Inappropriate administration can be dangerous. Many unscrupulous non ISI (Indian Standards Institute) pharmaceutical companies add iodine or thyroid hormone to their multimineral polyvitamin formulations. Sometimes they use thyroid gland extract from other animals as then the formulation can be labelled a “natural” product. Such supplements decrease fatigue and increase the appetite. Parents are happy as the child seems to eat more. Eventually, however side effects may appear. The natural function of the gland is suppressed. When the “tonic” is stopped, hypothyroidism sets in.

Remember:

Always use iodised salt

Read the fine print on any nutritional supplement, health drink or tonic that you and your family may have be taking

Do thyroid function tests as part of your master health check up

Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in