Is there Good and Bad Cholesterol?

Copyright 2005 Kristy Haugen Many classify cholesterol as good and bad. This is not true. Cholesterol is simply cholesterol. When thinking of good and bad, many are referring to HDL's and LDL's. HDL refers to high density lipoprotein while LDL refers to low density lipoprotein. Lipoproteins are merely cholesterol carriers. Lipoproteins are part lipid (fats) and part protein. The reason for this structure is proteins are soluble in water whereas fats are insoluble in water. The protein portion is used to transport the lipids through the blood. Since blood is comprised mostly of water, the lipid portion would not travel without the protein portion. HDL's consist of about half protein and half lipid; whereas LDL's are about a quarter protein and three quarters lipid. The function of the HDL is to bring cholesterol to the liver for recycling or elimination. Low density lipoproteins transport cholesterol to the rest of the body for building tissues. Cholesterol by chemical structure is an alcohol, because of the hydroxyl group (OH). Remember, ethanol (found in alcoholic beverages and gasoline) is also an alcohol but a much smaller alcohol. Cholesterol contains a four ring region that is characteristic of all steroid hormones (estrogen and testosterone). However, combination of the steroid ring structure and the hydroxyl group classify cholesterol as a sterol. Cholesterol has many functions. Cholesterol is the precursor to all steroid hormones produced in the body. This includes mineralcorticoids, glucocorticoids, and the sex hormones. Cholesterol is found in every cell. Cholesterol regulates the cell membranes fluidity. This prevents the cell from becoming too rigid or too fluid. Cholesterol helps keep the cell membranes intact. Cholesterol helps to build strong bones and muscles, and maintains libido and fertility. Cholesterol assists in regulating the blood sugar. Cholesterol helps to protect against infectious disease and repairs damaged tissue. Cholesterol is required to form vitamin D. Cholesterol is a component of lipid rafts, this helps to secure proteins involved in cell signaling. When sleeping at night, our brain synthesizes cholesterol to benefit our mood and increase our memory. Cholesterol supports the nervous system, in which cholesterol is a vital component of the myelin sheath. The myelin sheath allows neurons to conduct impulses with each other. Cholesterol has been found to be the rate limiting factor found in the formation of synapses, this formation is necessary for learning and the formation of memories. Cholesterol is used by the liver to synthesize bile acids. The liver makes about two grams of cholesterol daily. However, under stressful conditions the production of cholesterol increases to produce more adrenal and stress hormones. Bile acids are secreted into the small intestine to emulsify fats, aiding in digestion. Many studies cannot correlate eating foods containing cholesterol with an increase in blood cholesterol. Eating a diet high in meat and fat does not necessarily indicate heart disease. For example, the Eskimos live on a diet rich in meat and fat. The Eskimos have low cholesterol levels. Many populations that consume a high percentage of animal fats have less heart disease. Why? Animal fats are more resistant to oxidative damage. Many do not realize that cholesterol plaques are often there to protect a damaged artery. Many need to understand that a clogged artery is better than a ruptured one. Although elevated cholesterol levels are associated with heart disease, cholesterol may not be the cause. If cholesterol is not the cause of heart disease, what are the causes? Many factors may contribute to cardiovascular disease. Heart disease can be associated with deficiencies in a few minerals (copper, zinc, magnesium). Toxicity in calcium can assist in hardening of the artery walls. Increased homocysteine (amino acid found in vitamins b6 and folic acid) levels are a factor in heart disease. Deficiencies of vitamin C and the amino acid lysine cause decreased collagen synthesis. Also, hypothyroidism is associated with heart disease. Certain types of infections and inflammations are related to heart disease (dental infections). High blood pressure can lead to heart disease. Smoking, diabetes, obesity, caffeine, and a sedentary lifestyle increase the risk of heart disease. Finally, genetic factors play a part in heart disease. Any oxidative damage from vegetable oils contributes to heart disease. Hydrogenated fats found in margarine, dressings, fried foods contribute to heart disease. Hydrogenation produces trans-fatty acids. These are non-naturally occurring fatty acids that contribute to inflammation, one of the causes of heart disease. Cholesterol has a bad reputation and many misunderstand. The truth to the importance of cholesterol is simply not widespread enough. Cholesterol's role in heart disease cannot be linked. When understanding what may cause heart disease, total cholesterol is not as important as the ratio of HDL's to LDL's. This organic compound is essential for life as we know it.