The Thyroid, Cholesterol Connection
January 16, 2005
SUNDAY, Jan. 16
(HealthDayNews) -- High cholesterol is a well-known health problem
among Americans, particularly those at risk for stroke or heart disease.
By comparison, thyroid disease is a relatively obscure ailment, with many
people unable to say where the gland is and what it does.
What many people also don't know is that a malfunctioning thyroid gland can
cause high and potentially deadly levels of cholesterol in the blood.
An estimated 27 million Americans have an overactive or underactive thyroid
gland, but more than half remain undiagnosed, according to the American
Association of Clinical Endocrinologists.
The thyroid gland is located in the middle of the lower neck, below the voice
box and just above your collarbone. It is shaped like a bow tie, with two halves
called "lobes" connected by an "isthmus" in the middle, according to the
American Academy of Otolaryngology -- Head and Neck Surgery.
"The thyroid gland regulates the metabolic functions of the body in virtually
every cell," said Dr. Carlos Hamilton, president of the American Association of
Clinical Endocrinologists. "Everything from the brain to the skin is affected by
the hormone made by the thyroid gland."
And if the gland goes haywire, or comes under attack from disease, the
consequences can be serious.
January is Thyroid Awareness Month, and endocrinologists and other clinicians
are using the occasion to educate people about the risks posed by thyroid
If the thyroid gland is producing too little thyroid hormone -- a condition
called hypothyroidism -- the body's metabolism starts to slow down.
That can lead to high cholesterol levels in the blood, as the lack of thyroid
hormone slows the liver's ability to process blood, said Dr. Paul Jellinger,
president of the American College of Endocrinology.
"The sponge-like activity of the liver to soak up excess cholesterol from the
blood doesn't work as well as it should with low levels of thyroid," Jellinger
This causes an increased risk of cholesterol build-up in the arteries and
around the heart, increasing the risk for heart disease.
Hypothyroidism is the most common secondary cause of high cholesterol after
diet, according to the National Cholesterol Education Program.
Ninety percent of patients with hypothyroidism have increased cholesterol,
and the average blood cholesterol levels of patients with an underactive thyroid
are often 30 percent to 50 percent higher than desirable.
Hypothyroidism also has other effects. "It slows you down," Hamilton said.
"It makes you lethargic and fatigued." Your hair becomes brittle, and your skin
becomes dry. You become cold much easier than the average person.
"Everything's running on a lower gear," Jellinger said. "It's like an
eight-cylinder engine running on four cylinders."
Women are far more likely to have thyroid disease. More than eight out of 10
patients with the condition are women.
Pregnant women and the elderly are particularly affected by
Nearly one of 50 women in the United States is diagnosed with hypothyroidism
during pregnancy, and 5 percent to 17 percent of women are diagnosed with the
The incidence of hypothyroidism also increases with age. By 60, as many as 17
percent of women and 9 percent of men have an underactive thyroid.
The good news is that high cholesterol caused by hypothyroidism is highly
treatable, Jellinger said. Much of the time, thyroid patients can avoid using
cholesterol-lowering drugs simply by treating their condition.
"As the thyroid abnormality becomes more intense, the ability to lower
cholesterol is very striking," Jellinger said. "Often the only treatment needed
to lower cholesterol is thyroid medication."
People with an overactive thyroid gland, or hyperthyroidism, also must be
concerned about cholesterol.
Their condition causes a high metabolic rate that can artificially lower
cholesterol levels, Jellinger said. People being treated for hyperthyroidism
must watch their cholesterol levels as their metabolism returns to a normal
Both hyperthyroidism and hypothyroidism are easily treated through
medication, said Dr. Bill Law, an endocrinologist in Knoxville, Tenn.
"One little pill a day, very inexpensive, and no side effects," Law said. "If
you have to have a disease, it's a good one in terms of treatment."
The bad news is the disease is genetically influenced more than anything
else, meaning there's little you can do to prevent its onset.
"Other than maintaining good nutrition, there isn't really much a person does
that affects their thyroid gland," Hamilton said.
The diseases are diagnosed through a simple blood test that family physicians
can perform in their office.