Cholesterol

Cholesterol is a natural fat-like substance found in the body of all animals, including humans, and transported in the bloodstream. Cholesterol is an essential component of all cell membranes as well as part of the myelin sheath, a substance that covers nerve fibers and facilitates the transmission of nerve impulses.  Cholesterol is also involved in the production of certain vitamins, hormones, and bile.

There are no symtpoms to indicate high cholesterol, so people are often completely unaware that their cholesterol level is high.  Testing cholesterol levels (see Cholesterol Testing) is important because lowering high cholesterol levels can help to reduce the risk of heart disease, heart attack, or stroke.

There are two main varieties of cholesterol; low-density lipoprotein (LDL), the “bad” cholesterol, and high-density lipoprotein (HDL), the “good” cholesterol.  Your total cholesterol count is determined by these two types of cholesterol along with triglycerides.

LDL-Cholesterol

Excess LDL cholesterol, along with other components, can build up in the arteries, forming a plaque that can cause the arteries to narrow and reduce blood flow.  It can also cause a hardening of the arteries known as atherosclerosis.  Heart attacks and strokes are often caused by a clot that is formed and blocks an already-narrowed artery.  According to The National Heart, Lung and Blood Institute (NHLBI), the optimal level for LDL-cholesterol is less than 100mg/dL. High levels include anything 160mg/dL or higher. While anything in the 130mg/dL to 159mg/dL range is considered borderline high, it definitely doesn’t hurt to take action at this point.

HDL-Cholesterol

Higher levels of HDL cholesterol appear to reduce the risk of heart attack while lower levels appear to increase the risk of heart disease.  HDL is thought to carry LDL to the liver where it is removed from the body in the form of bile.  The higher the HDL level, the cleaner the blood.  Considering this, it’s important to understand HDL and how to increase its presence within your body.   According to the The National Heart, Lung and Blood Institute (NHLBI), a level less than 40 mg/dL is low and is considered a major risk factor because it increases your risk for developing heart disease. HDL levels of 60 mg/dL or more help to lower your risk for heart disease.

Triglycerides

Triglycerides can also raise heart disease risk. Levels that are borderline high (150-199 mg/dL) or high (200 mg/dL or more) may need treatment in some people.

Our bodies synthesize all the cholesterol we need to maintain good health, so any cholesterol originating from dietary sources is not only unnecessary, it can become quite dangerous by building up cholesterol-laden plaque in our arteries. This cholesterol buildup and subsequent arterial narrowing can cause the signs and symptoms of coronary heart disease.

Coronary Heart Disease

Coronary Heart Disease (CHD), also known as coronary artery disease, refers to the failure of coronary circulation and  is caused by the buildup of cholesterol in the arteries, reducing our body’s ability to supply oxygen and nutrients to our heart.  If insufficient oxygen-carrying blood reaches the heart you may experience chest pains called angina.  If blood supply is completely cutoff in a coronary artery the result is a heart attack. Heart disease is the number one killer of both men and women in the United States.

Symptoms of Coronary Heart Disease

• Angina: Chest pains experienced when insufficient oxygen-carrying blood is reaching the heart.
• Irregular heartbeat
• Chest Pain:  Chest pains during exertion which may be relieved by rest.
• Heart attack:  Blood supply to a portion of the heart is completely blocked.  This is often caused by the sudden appearance of a blood clot in an already cholesterol-narrowed coronary artery.
• Shortness of breath

Cholesterol levels tend to vary throughout the different regions of the world. In regions where blood cholesterol levels are lower, such as in Japan, the rates of heart disease are lower. On the other hand, countries with high levels of blood cholesterol have very high rates of heart disease. It is also true that different regions with similar blood cholesterol levels have similar rates of heart disease, indicating that factors other than cholesterol have an influence on the risk for heart disease.

If you believe you may have high cholesterol or if your family has a history of high cholesterol, your doctor can help you determine your complete lipid profile and recommend a course of action, if necessary.