Health & Medicine

Weight loss, gain? Check the thyroid

If you have been struggling to lose or gain weight, it doesn't hurt to get your thyroid checked. Thyroid problems are extremely common, affecting approximately 30 million Americans, and they are five times more common in women than in men.

The most common functional thyroid problem is an underactive thyroid (hypothyroidism). An overactive thyroid (hyperthyroidism) is caused by Grave's disease or nodules producing too much hormone.

A goiter (enlarged thyroid) is a common problem, and is almost always benign. An ultrasound is used to look for nodules, but a biopsy is needed to check nodules for cancer.

What are the symptoms of a thyroid problem? A functional thyroid problem may cause abnormalities in hormone levels or metabolism, leading to fatigue and changes in weight and the menstrual cycle.

A goiter or nodule can put pressure on or irritate the windpipe. This may cause a sensation of being choked or a need to constantly clear the throat or cough especially when lying flat. Swallowing problems are also common. Many patients complain of food hanging in the low neck, especially breads and meat.

The nerves to the vocal cords run behind the thyroid, so the voice can occasionally be affected.

How is a thyroid problem diagnosed? Thyroid function is checked with a simple blood test that measures thyroid stimulating hormone. If your thyroid isn't making enough hormone, your hormone level will be elevated. A normal result does not exclude the chance of thyroid nodules or cancer.

However, if your thyroid lab tests are normal, then any weight fluctuation has other causes. Poor diet, lack of exercise and lack of sleep, as well as many other factors, can result in weight gain and fatigue.

Ultrasound is the best way to evaluate nodules or goiters. Ultrasound shows the size and characteristics of nodules but only a biopsy can determine if a nodule is cancerous.

In general, nodules greater than a centimeter should be biopsied with fine needle aspiration.

How are thyroid problems treated? An underactive thyroid can be controlled by taking a thyroid hormone pill. An overactive thyroid usually requires radioactive iodine treatment or surgery.

Thyroid cancer must be removed. Thyroidectomy (removal of the entire thyroid gland) and removal of surrounding lymph nodes with or without radioactive iodine is recommended.

No other treatments "shrink" a goiter or nodules. If the biopsy of a goiter or nodule is benign, then the thyroid should only be removed if its size causes problems for the patient, such as producing too much hormone or causing pressure in the throat. Symptomatic goiters/nodules can be removed safely with surgery through a small incision in the low neck.

Are thyroid problems preventable? Most thyroid problems are not preventable. Many conditions, including underactive and overactive thyroids, nodules and thyroid cancer, run in families. Previous radiation treatment increases the risk for thyroid cancer.