Briefly, not every type of cholesterol is harmful for health. There are two types of cholesterol – HDL (high density lipoprotein or good cholesterol) and LDL (low density lipoprotein or bad cholesterol). While bad cholesterol causes blockages in the arteries, lower cholesterol helps transportation of triglycerides in the liver for excretion.
Details about Good Cholesterol and Bad Cholesterol –
Definition: Bad cholesterol is a type of fat in the blood, of which high levels can cause health problems, it tends to accumulate in the arteries (atherosclerosis) and hinder blood circulation. Good cholesterol includes high-density lipo-proteins, also found in the blood stream, which helps transport triglycerides to the liver for excretion or reuse. –
Functions: The main function of “bad cholesterol” is to carry cholesterol to various body tissues (organs) and arteries. “Good cholesterol’s” function is to carry cholesterol from the arteries and tissues to the liver and other organs such as the ovaries, adrenal glands and testicles. –
Recommended Levels: The recommended level of bad cholesterol should not exceed 2.6 mmol/L blood. Recommended level of good cholesterol exceed 1.5 mmol/L of blood. Mmol/l is millimoles/liter, and is the world standard unit for measuring glucose in blood. Specifically, it is the designated SI (System International) unit. “World standard” is not universal. Not only the US, but a number of other countries use mg/dl. A mole is about 6*10^23 molecules. –
Cholesterol Sources: “Bad cholesterol” is found in foods high in trans fats, refined carbohydrates (such as sugar and white flour), foods high in cholesterol (such as egg yolks, liver and kidneys of animals, dairy products and alcohol). “Good cholesterol” sources include onions, foods rich in Omega 3 fatty acids (such as flax seed oil and fish meat) and fiber-rich foods (cereal, oatmeal, bran etc.). –
Structural and functional differences:
“Good cholesterol” – Lipo-proteins are complex apolipoproteins (proteins that bind lipids to form lipoproteins – for transport of the lipids through the circulatory system) and phospholipids (major component of all cell membranes). Good cholesterol contains the smallest molecules of all lipid molecules, which are high density due to their protein content. The cholesterol transported to the liver is excreted in bile and then into the intestines. On the other hand, the cholesterol transported to other parts of the body is used for the synthesis of steroid hormones. Other functions of “good cholesterol” include suppressing oxidative processes from cells, anti-inflammation, endothelial activation (the thin layer of cells that lines the interior surface of blood vessels and lymphatic vessels) and blood clotting regulation. “Bad cholesterol‘” – A molecule of bad cholesterol (LDL) consists of a single molecule of apolipoprotein (see above) that helps the circulation of fatty acids, and the only function of these less dense molecules is to carry cholesterol to tissues and arteries.
The Effects of High Cholesterol Levels on Health
The higher the level of bad cholesterol in the blood is higher, the higher the risk of developing coronary artery (heart) disease. When the level of bad cholesterol in the blood decreases, the risk of heart disease drops respectively. Coronary artery disease are disorders caused by the accumulation of plaque inside the coronary arteries. Plaque formation in the arteries restricts the flow of oxygen-rich blood to the heart. Eventually, part of the plaque can detached from the walls of the arteries causing the formation of a blood clot. If the clot is big enough, the blood flow can be blocked partially or totally. In this case, the affected person may develop angina or a heart attack.