The High Cholesterol-Thyroid Connection


senior member
Concord, NH
Your thyroid is a tiny, butterfly-shaped gland in your neck that can cause a big, surprising problem elsewhere in your body. Recently, I learned that the real cause of high cholesterol in as many as 10 million Americans is an undiagnosed thyroid problem. Thats right -- your thyroid might be causing your high cholesterol.

An Underreported Phenomenon

To learn more about this underreported phenomenon, I spoke with endocrinologist Irwin Klein, MD, professor of medicine and cell biology and chief of the Thyroid Unit at North Shore University Hospital in Manhasset, New York . Dr. Klein has been studying the link between thyroid and heart health for three decades. He told me that thyroid hormones have a profound impact on the heart and cardiovascular system. Thyroid dysfunction, specifically hypothyroidism or an underactive thyroid, can lead to high cholesterol as well as changes in blood pressure, vascular resistance, rhythm disturbances and more.

According to Dr. Klein, many primary-care doctors arent aware of this connection, but its irrefutable -- nine out of 10 people with hypothyroidism have high cholesterol. The good news is that you can easily detect and correct many primary thyroid dysfunctions and, along with them, the resulting high cholesterol. Dr. Klein shared practical advice on how to control thyroid-related cholesterol problems.

Hypothyroidism: What You Need to Know

Surprisingly, many people with hypothyroidism dont know they have it. This most common type of thyroid disease affects up to 15% of adult females -- especially women over age 50 -- and after age 80, it affects both genders equally. The problem often is caused by uncontrolled inflammation and/or autoimmune disease. The body stops manufacturing effective amounts of thyroid hormones, resulting in symptoms such as mild lethargy and fatigue. Left untreated, hypothyroidism can worsen over time and result in serious health challenges -- not only high total cholesterol, but also elevated levels of harmful low-density lipoproteins (LDL), apolipoprotein B and triglycerides.

Some people with hypothyroidism have symptoms distinct enough that they know something is wrong -- but not all do. And, as you can see from the list below, the typical symptoms are easy to attribute to other causes. Symptoms can include...

Severe fatigue, low energy and weakness.
Increased sensitivity to cold.
Depression, confusion and memory loss.
Pale, dry skin.
Brittle fingernails and hair.
Puffy face.
Hoarse voice or hearing loss.
Joint and/or muscle pain.
Heavy menstrual periods.
Weight gain.
Unexplained anemia.

If you experience chronic symptoms such as these, see your primary-care provider for an assessment of your thyroid health. Or, if you are diagnosed with high cholesterol, ask your physician to give you a thyroid-stimulating hormone (TSH) test. This simple and cost-effective blood test to diagnose many thyroid diseases is often overlooked, says Dr. Klein, even though both the National Cholesterol Education Program and the Food and Drug Administration recommend thyroid testing for people with high cholesterol.

An Easy Solution

Fortunately, treatment of hypothyroidism is usually simple, straightforward and effective -- one thyroid-hormone replacement pill once a day. If you are among the roughly one in 20 Americans whose cholesterol is elevated due to an underactive thyroid, chances are that a thyroid-replacement pill will simultaneously control your cholesterol levels.

Once your physician determines the correct dosage, thyroid-replacement pills cause few side effects, since they essentially provide in pill form what your body should be producing naturally. This medication also is relatively inexpensive.

In contrast, cholesterol-lowering statin drugs have significant side effects and are costly. For example, Lipitor costs between $113 and $160 per month. And, most importantly -- statins simply may not be as effective in treating high cholesterol in people with hypothyroidism since they fail to address the underlying problem.


Irwin Klein, MD, endocrinologist and professor of medicine and cell biology, NYU School of Medicine, New York City, and associate chairman of the department of medicine, North Shore University Hospital , Manhasset , New York . Dr. Klein is the chairman of the American Thyroid Association Research Committee and is on the editorial boards of The Journal of Clinical Endocrinology & Metabolism... Endocrinology... Thyroid and Clinical Endocrinology