Cholesterol - Omran Desouki

By singingbeagle.(2008). Happiness on a bun [Photograph]. Retrieved from: http://www.flickr.com/photos/singingbeagle/3701204435/

Cholesterol is one of the most important molecules in a human being. It was discovered in 1815 by Chevreul who named it “cholesterine”¹

Cholesterol is synthesized in the liver⁶; it helps in maintaining cell membranes by making them more rigid and plays major roles in vitamin regulation, myelin formation, the endocrine system, the immune system, and in lipid rafts. Therefore, without this molecule, a human being cannot survive⁹.

It is an amphipathic molecule and is slightly soluble in water, so it is transported in the blood via lipoproteins^{3, 5}. There are two types of lipoproteins, High Density Lipoprotein (HDL) and Low Density Lipoprotein (LDL). LDLs transport cholesterol molecules from the liver to the body, While HDLs transport excess cholesterol back to the liver to be recycled⁸. The ideal blood concentration of LDLs is 1.8mmol/L and below, and that for HDLs is 1.6mmol/L and higher⁷.

You can also get cholesterol through consuming animal-based foods, and dairy products that are high in fat¹¹. However, the recommended daily intake is 300 mg according to the United States Department of Agriculture (USDA) ⁸.

An increased concentration of cholesterol in the blood due to a bad diet or because of a hereditary disorder, can lead to the formation of plaques in the arteries. These plaques narrow down the arteries in a process called “Atherosclerosis”. This causes the decrease of blood flow and can lead to some serious health problems such as heart attacks⁸.

Cholesterol is an essential molecule for human survival, but it can be deadly in some cases… so being cautious of what you eat might be the best bet!!!

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11. Niedziocha, L. (2011). Daily Recommended Cholesterol Intake. Retrieved November 5, 2012 from: http://www.livestrong.com/article/391588-daily-recommended-cholesterol-intake/