If you're like most people, the mention of the word "cholesterol" probably conjures up negative ideas because of its famed association with heart disease. Yet your body needs this soft, waxy substance to remain healthy. It serves as as a component of all cell membranes, as well as a precursor of steroid hormones and bile acids. As a result, abnormally low cholesterol levels, or cholesterol depletion, can have ill effects on your health.
Description
Although "cholesterol depletion" and the term "hypocholesterolemia" both refer to abnormally low cholesterol levels, there is a small nuance. Scientists generally use the phrase "cholesterol depletion" to describe the artificial reduction of the body's cholesterol content below normal levels. In contrast, hypocholesterolemia has natural causes. According to physician Jeffrey Halter, a total cholesterol concentration of less than 160 mg/dL--milligrams per deciliter--is considered abnormally low.
Causes
According to physician Beatrice Golomb, cholesterol depletion may result from the prolonged use of certain medications, especially cholesterol-lowering statins. Additional causes for low cholesterol levels include an overactive thyroid gland, malabsorption of nutrients from the intestines, malnutrition, liver disease, chronic infections and inflammation, cancer, chronic involuntary weight loss, diabetes, and chronic obstructive pulmonary disorder.
Musculoskeletal Effects
The lack of sufficient cholesterol limits your body's ability to produce certain proteins involved in muscle metabolism and function. Physician Terry Jacobson notes that cholesterol-lowering drugs can cause myalgia, myopathy and rhabdomyolysis. Myalgia and myopathy both manifest with muscle pain, tenderness, and/or weakness. However, myopathy also includes muscle dysfunction. Rhabdomyolysis is a potentially life-threatening condition, which features a rapid breakdown of skeletal muscle fibers.
Endocrine Effects
Cholesterol depletion can disrupt blood glucose control. For instance, a 2008 issue of "Endocrinology" reported that abnormally low cholesterol levels limit your body's ability to produce and secrete the pancreatic hormones insulin and glucagon. Insulin normally enables your cells to pick up glucose from the blood when blood sugar is high. Glucagon triggers the release of glucose in the blood when levels are low.
Other Effects
Scientist Fuzhen Xia and colleagues have reported cholesterol's involvement in maintaining membrane fluidity and insulation. Because this role also applies to brain and nerve cells, very low cholesterol can lead to nervous system dysfunctions, such as thought-processing disturbances, nerve damage or psychiatric problems. Since cholesterol also serves as a precursor of bile acids and steroid hormones, depletion may lead to digestive problems, immune dysfunction, sexual dysfunction, skin problems and sleep disorders.
Considerations
The risk of cholesterol depletion tends to be greater in older individuals. Additionally, Dr. Halter reports results of 19 studies showing a 40 to 50 percent higher risk of non-cardiovascular deaths in individuals with cholesterol concentrations lower than 160 mg/dL, compared to those with borderline high levels ranging from 200 to 239 mg/dL.
Prevention/Solution
According to Scientists Pamela Champe and Richard Harvey, a healthy body can produce enough cholesterol to meet its own needs, even with a cholesterol-free diet. Because very low cholesterol levels often result from an underlying disease, it's difficult to consider dietary supplementation apart from your overall health care. In the case of drug-induced cholesterol depletion, however, Dr. Jacobson remarks that the main factors to address are drug dosages and drug interactions.
References
- "Hazzard's Geriatric Medicine and Gerontology" (6th Edition); Jeffrey Halter, M.D. et al.; 2009
- "Endocrinology"; Inhibition of Cholesterol Biosynthesis; Fuzhen Xia, Li Xie et al.; July 2008
- "Mayo Clinic Proceedings"; The Safety of Aggressive Statin Therapy--How Much Can Low-Density Lipoprotein Cholesterol Be Lowered?; Terry Jacobson, M.D.; September 2006
- "American Journal of Cardiovascular Drugs"; Statin Adverse Effects; Beatrice Golomb, M.D.; June 2008
- "Lippincott's Illustrated Reviews of Biochemistry"; Pamela Champe, Ph.D. and Richard Harvey, Ph.D.; 2006
