Brenda Blackburn had been feeling more tired than she could ever remember. At first, the 50-year-old Harford County woman attributed the debilitating fatigue to her diabetes, but it only got worse. Finally she couldn't walk up and down stairs without weakness and exhaustion.
Her physician, endocrinologist James Mersey, tested her thyroid, the gland responsible for regulating the body's metabolism, to determine how well it was functioning. The results surprised her: "He told me it was literally dead!"
After several months of taking thyroid hormone replacement medication -- a regimen that continues for life -- Blackburn regained her normal level of energy. And she began to realize that other physical changes she had noticed in recent years -- such as thinning hair -- were also due to an underactive thyroid rather than to aging or menopause.
Blackburn's misunderstanding of her symptoms is common. Although an estimated 22 million Americans possess some form of thyroid disease, perhaps as many as a third do not even realize they are affected, according to the Thyroid Society for Education and Research in Houston.
The thyroid gland, located in the neck below the Adam's apple, is responsible for controlling the rate at which the body uses energy for its various chemical processes. Auto-immune disorders, surgery and radiation can cause the thyroid to malfunction, either slowing down the body, or speeding it up, to unhealthy levels.
Like auto-immune disorders in general, thyroid disorders are far more common in women than in men.
Hypothyroidism
Studies show that by the age of 65, more than 10 percent of American women have an underactive thyroid, a condition known as hypothyroidism. This disorder can be very hard to recognize, doctors say, because the constellation of symptoms that signal sluggish metabolism can also suggest other conditions, such as depression.
Because hypothyroidism is so common, the American College of Physicians and the American Society of Internal Medicine now recommend routine screening for thyroid function in women over the age of 50.
"A lot of hypothyroidism goes unnoticed because the symptoms seem nonspecific and are gradual in onset," says endocrinologist Paul Ladenson at Johns Hopkins Hospital. "People chalk them up to life stress. Or they just think, 'Oh well, I'm getting older.' "
