Metformin is a medication prescribed to control blood sugar levels in patients with type 2 diabetes. Metformin is also prescribed for some patients with polycystic ovarian syndrome -- or PCOS, a hormonal disorder in women. Cholesterol is a waxy substance found in blood and in cells throughout the body. Although cholesterol has important functions in maintaining health, diabetic patients often have unhealthy cholesterol levels in blood, which contributes to their increased risk of heart disease and stroke. Metformin has been shown to have beneficial effects on cholesterol levels.
Metformin
Metformin is an oral medication used in treatment of type 2 diabetes, either alone or in combination with other treatments and drugs. In type 2 diabetes, the body fails to make sufficient insulin in response to increased blood sugar or the cells are resistant to the action of insulin. Insulin is a hormone secreted by the pancreas that helps the body use and store blood sugar.
Metformin belongs to a class of drugs called biguanides, which primarily act in the liver to decrease sugar production. In addition, Metformin increases glucose uptake and utilization in muscle and fatty tissues and improves insulin sensitivity of cells.
Benefits and Concerns
Unlike some other diabetes medications, Metformin does not increase the insulin secretion by the pancreas. Metformin generally facilitates blood sugar control without hyperinsulinemia -- excess insulin in blood -- or weight gain. Metformin may also have uses in other diseases, including cancer. A study published in "Diabetes Care" in 2010 found that women with type 2 diabetes taking metformin for longer than five years were 56 percent less likely to develop breast cancer than those on other medications.
Metformin may also have some undesirable side effects, some of which, like lactic acidosis, may be serious. Common side effects include diarrhea, indigestion, nausea and headaches. Consult your physician about the benefits and harms of metformin specific to your health.
Cholesterol
Cholesterol is a fatty substance that is transported throughout the body by carrier proteins called lipoproteins. Cholesterol bound by high- and low-density lipoproteins, or HDL and LDL cholesterol, and trigylcerides, another kind of fat, make up the total cholesterol count. HDL cholesterol, or "good cholesterol," is inversely associated with risk of heart disease. An excess of LDL cholesterol, or "bad cholesterol," can build up in blood vessels causing artherosclerosis -- or narrowing and reduced flexibility of blood vessels-- and increases the risk of heart attack and stroke. The risk of dyslipidemia -- high triglycerides, high HDL or low LDL cholesterol in blood -- is increased by diabetes, according to the American Heart Association.
Effects on Cholesterol
The American Diabetes Association indicates that metformin has desirable effects on all types of cholesterols. Significant desirable effects observed in some, but not all, clinical trials include decreases in triglycerides and LDL cholesterol and increases in HDL cholesterol. For instance, one study, published in "Annals of Medicine" in 1990, found that metformin decreased total and LDL cholesterol in diabetic patients with type IIB hyperlipidemia -- an inherited disorder in which very low-density lipoprotein and LDL cholesterol are elevated. Another study, published in "New England Journal of Medicine" in 1995, found that metformin, either alone or in combination with another drug, decreased triglycerides as well as total and LDL cholesterol in diabetes patients.
