Treating High Cholesterol Related to Hypothyroidism

The first step is normalizing your thyroid function

Cholesterol, thyroid, high-cholesterol
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Cholesterol is a waxy substance that occurs naturally in all parts of your body. When you have an excess of cholesterol, it ends up being deposited in your arteries, including your coronary arteries, where it can eventually block arteries and cause heart disease.

Hypothyroidism—an underactive thyroid—is present in up to 13 percent of people with elevated levels of cholesterol (called hyperlipidemia).

This is why professional societies like the National Cholesterol Education Program and American Association of Clinical Endocrinologists advise doctors to screen their patients for hypothyroidism when a new diagnosis of hyperlipidemia arises. 

Treat Your Underactive Thyroid First

If a diagnosis of hypothyroidism is found, treatment with thyroxine (T4) replacement, can improve cholesterol levels.

In fact, according to a study in JAMA, 60 percent of people with a new diagnosis of hypothyroidism and hyperlipidemia had a resolution of their elevated cholesterol levels once their thyroid function was restored. This percentage may be higher, as well, considering not everyone in the study had their cholesterol levels rechecked after restoration of their thyroid function.

Lowering Your Cholesterol

In some instances, your cholesterol levels remain elevated, despite treatment of your underactive thyroid.

Under the guidance of your doctor, the first step to lowering your cholesterol is to lose any excess extra weight and begin a regular exercise routine. Along with weight loss and exercise, a change in your diet is important. 

Diet
A primary line of attack in lowering your cholesterol can be a change in your diet.

This entails adopting a  low-saturated fathigh-fiber diet.

A low saturated fat diet means avoiding foods like:

  • Red meat
  • Fatty meats that are not trimmed
  • Processed meats
  • Full-fat dairy products like whole milk and butter
  • Baked goods and sweets like donuts
  • Fried foods.

Instead, eat a rainbow of fruits and vegetables and choose protein-rich foods that are high in unsaturated fats, like fatty fish (for example, salmon and albacore tuna) and unsalted nuts, like almonds and walnuts. Lean meats and chicken without the skin are also good protein options.

Whole grains, like whole grain bread, pasta, and brown rice, provide you fiber, which can help lower your LDL cholesterol (called your "bad" cholesterol, since it's the one that clogs your arteries).

Lastly, when cooking, avoid using saturated oils like coconut oil, palm oil, and palm kernel oil. Instead use canola, corn, olive, or safflower oils. 

Medication

As noted earlier, if you make changes in your diet and lifestyle and your LDL-cholesterol level still remains quite high, or you are at a high risk for heart disease from the start, your doctor may also suggest you take a cholesterol-lowering medication.

Statins are considered the primary choice for lowering LDL levels and include:

  • Lipitor (atorvastatin)
  • Lescol (fluvastatin)
  • Mevacor, Altoprev (lovastatin)
  • Pravachol (pravastatin)
  • Crestor (rosuvastatin calcium)
  • Zocor (simvastatin)

There are also combination medications that contain a statin and another cholesterol-lowering drug. These include:

  • Advicor (lovastatin and niacin)
  • Vytorin (simvastatin and ezetimibe)

Fibrates such as Gemfibrozil (Lopid) or fenofibrate (Tricor) are typically given to lower triglyceride levels. In some cases, high doses of nicotinic acid, also known as "niacin," are recommended for reducing triglyceride levels and raising HDL. Niacin is available over-the-counter, but should be taken under the supervision of a physician.

Resins are drugs that bind with bile acids in the digestive tract, forcing the liver to clear cholesterol and thereby reducing LDL. These drugs include cholestyramine (Questran, Questran Light) and colestipol (Colestid).

A Word From Verywell

If you have been newly diagnosed with high cholesterol, be sure to have your doctor screen you for hypothyroidism. He can do this by ordering a blood test called TSH (thyroid stimulating hormone). 

If your cholesterol is still high, despite normalization of your thyroid function, you and your doctor can determine if you need a cholesterol-lowering medication (in addition to adopting healthy lifestyle habits).

In the end, cholesterol-lowering foods can not only be a healthy part of your plan, but they taste great and are a wonderful addition to your diet.

So go ahead, and enjoy a slice of avocado on whole grain toast for a snack, instead of reaching for that cookie jar.

Sources:

ACC/AHA Release Updated Guideline on the Treatment of Blood Cholesterol to Reduce ASCVD Risk, Am Fam Physician. 2014 Aug 15;90(4):260-265. http://www.aafp.org/afp/2014/0815/p260.html.

American Heart Association. (2016). How Can I Improve My Cholesterol?

Willard DL, Leung AM, Pearce EN. Thyroid function testing in patients with newly diagnosed hyperlipidemia. JAMA Intern Med. 2014 Feb 1;174(2):287-89.