High cholesterol can be inherited, but it can also develop in people without a family history of high cholesterol. Two inherited conditions are familial combined hyperlipidemia (occurring in 1 in 100 individuals), and familial hypercholesterolemia (occurring in 1 in 500 people). People with these conditions are at very high risk of premature heart attack and stroke, and need aggressive medical treatment. Family members should be screened for high cholesterol so they can be treated as early as possible.
The two most common causes of noninherited cholesterol elevation are an unhealthy diet and diabetes. Consumption of large amounts of saturated fat, cholesterol, and too many calories will lead to high LDL cholesterol in most people. Low-calorie, low-saturatedfat diets cause significant reductions in cholesterol.
Diabetes leads to high LDL cholesterol mostly when blood glucose (sugar) levels are poorly controlled. Therefore, both type 1 and type 2 diabetics are at risk. Diabetic people have 2-6 times the risk for atherosclerosis compared to nondiabetics, and need to aggressively control other risk factors such as high blood pressure, obesity, diet, and smoking. Other causes of high LDL cholesterol include excessive alcohol intake, hypothyroidism (underfunctioning thyroid), kidney disease, HIV/AIDS, obstructive liver disease, hormones such as progesterone or steroids, and occasionally some medications like thiazide diuretics or beta-blockers (which are used to control blood pressure).
Symptoms of elevated cholesterol
Severe elevations in cholesterol as in familial hypercholesterolemia can lead to cholesterol deposits in the skin or on tendons called xanthomas. Unfortunately, most of the time hypercholesterolemia goes unnoticed until a catastrophe occurs, such as a stroke, heart attack, loss of circulation to a limb or to the kidneys, or ruptured aortic aneurysm. The consequences of these events include sudden death, chronic disability, long-term illness with frequent hospitalizations, and depression.