Cholesterol

hide

Cholesterol is a lipidic, waxy steroid found in the cell membranes and transported in the blood plasma of all animals. It is an essential component of mammalian cell membranes where it is required to establish proper membrane permeability and fluidity. Cholesterol is the principal sterol synthesized by animals, but small quantities are synthesized in other eukaryotes, such as plants and fungi. It is almost completely absent among prokaryotes, which include bacteria. Cholesterol is classified as a sterol.

Since cholesterol is essential for life, it is primarily synthesized de novo within the body. However excessive levels of cholesterol in blood circulation are strongly associated with progression of atherosclerosis. For an adult, typical total body cholesterol synthesis is about 1 gram per day (less if dietary intake is high) and total body cholesterol content is about 35 g. Average dietary intake in western societies is 0.2 - 0.3 grams. Cholesterol is excreted by the liver via the bile into the digestive tract. Typically about 50% of the excreted cholesterol is reabsorbed by the small bowel back into the blood stream.

The name cholesterol originates from the Greek chole- (bile) and stereos (solid), and the chemical suffix -ol for an alcohol, as François Poulletier de la Salle first identified cholesterol in solid form in gallstones, in 1769. However, it was only in 1815 that chemist Eugène Chevreul named the compound "cholesterine".

For more information about Cholesterol, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with cholesterol

results timeline


Vitamin B niacin offers no extra benefit to statin therapy in seniors already diagnosed with CAD

Medicine & Health / Research

created Nov 18, 2009 | popularity 5 / 5 (2) | comments 0

The routine prescription of extended-release niacin, a B vitamin (1,500 milligrams daily), in combination with traditional cholesterol-lowering therapy offers no extra benefit in correcting arterial narrowing and diminishing ...


The protein Srebp2 drives cholesterol formation in prion-infected neuronal cells

Chemistry / Biochemistry

created Nov 18, 2009 | popularity 4 / 5 (1) | comments 0

Prions are causing fatal and infectious diseases of the nervous system, such as the mad cow disease (BSE), scrapie in sheep or Creutzfeldt-Jakob disease in humans. Scientists of Helmholtz Zentrum München and Technische Universität ...


Prevalence of high LDL, or 'bad' cholesterol levels decreases in US

Medicine & Health / Health

created Nov 17, 2009 | popularity not rated yet | comments 0

Between 1999 and 2006, the prevalence of adults in the U.S. with high levels of LDL cholesterol, the "bad" cholesterol, decreased by about one-third, according to a study in the November 18 issue of JAMA. But a high percen ...


Some obese people perceive body size as OK, dismiss need to lose weight

Medicine & Health / Health

created Nov 17, 2009 | popularity 5 / 5 (1) | comments 0

Some obese people misperceive that their body size is normal and think they don't need to lose weight, according to research presented at the American Heart Association's Scientific Sessions 2009.


Fungi May Hold Key to Reducing Grapefruit Juice Interactions with Medications

Fungi May Hold Key to Reducing Grapefruit Juice Interactions with Medications

Chemistry / Biochemistry

created Nov 17, 2009 | popularity 5 / 5 (1) | comments 1

(PhysOrg.com) -- A fungus may help solve a problem of a grapefruit compound that interacts negatively with certain prescription drugs, according to studies by Agricultural Research Service (ARS) scientists.


Early end to key study on benefits of niacin, a B vitamin, in keeping arteries open was premature

Medicine & Health / Research

created Nov 16, 2009 | popularity 3.7 / 5 (3) | comments 0

Heart experts at Johns Hopkins are calling premature the early halt of a study by researchers at Walter Reed Army Medical Center and Washington Hospital Center on the benefits of combining extended-release niacin, a B vitamin, ...


Study raises new questions about Merck pill Zetia

Medicine & Health / Medications

created Nov 16, 2009 | popularity 5 / 5 (3) | comments 1

(AP) -- A new study raises fresh concerns about Zetia and its cousin, Vytorin - drugs still taken by millions of Americans to lower cholesterol, despite questions raised last year about how well they work.


No need to fast for cholesterol test

Medicine & Health / Research

created Nov 13, 2009 | popularity 5 / 5 (8) | comments 1

(PhysOrg.com) -- Patients do not need to fast before having their cholesterol tested, a major study has found.


Role of Statins in Reducing H1N1 Mortality Rates Studied

Medicine & Health / Research

created Nov 13, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- Vanderbilt University Medical Center researchers are studying statins, the class of drugs long associated with lowering cholesterol, as a way to reduce H1N1-related deaths.


Too much selenium can increase your cholesterol

Medicine & Health / Health

created Nov 12, 2009 | popularity 5 / 5 (2) | comments 0

A new study from the University of Warwick has discovered taking too much of the essential mineral selenium in your diet can increase your cholesterol by almost 10%.


Study: Kidney angioplasty brings risks, no benefit

Medicine & Health / Diseases

created Nov 11, 2009 | popularity not rated yet | comments 0

If you're among the hundreds of thousands of Americans with clogged kidney arteries, you might want to consider trying medicines before rushing into angioplasty to open them up. The pricey procedure is no more effective and ...


Findings suggest lipid assessment in vascular disease can be simplified, without the need to fast

Medicine & Health / Research

created Nov 10, 2009 | popularity 5 / 5 (1) | comments 0

Lipid assessment in vascular disease can be simplified by measuring either total and HDL cholesterol levels or apolipoproteins, without the need to fast and without regard to triglyceride levels, according to a study in the ...


Long-term statin use associated with decreased risk of gallstones requiring surgery

Medicine & Health / Diseases

created Nov 10, 2009 | popularity 5 / 5 (1) | comments 1

Use of the cholesterol-lowering drugs statins for more than a year is associated with a reduced risk of having gallstones requiring surgery, according to a study in the November 11 issue of JAMA.


Study suggests dentists can identify patients at risk for fatal cardiovascular event

Medicine & Health / Diseases

created Nov 05, 2009 | popularity 4 / 5 (1) | comments 0

A new study indicates dentists can play a potentially life-saving role in health care by identifying patients at risk of fatal heart attacks and referring them to physicians for further evaluation.


Scientists reveal a new mechanism that increases atherosclerosis in mice

Scientists reveal a new mechanism that increases atherosclerosis in mice

Medicine & Health / Research

created Nov 05, 2009 | popularity 5 / 5 (1) | comments 0

(PhysOrg.com) -- For all the good it does, a liver protein that senses and gets rid of drugs and pollutants from our body has a downside. For the first time, it has been shown that when it is chronically activated, ...