Cholesterol: The Complex Sterol that Plays a Crucial Role in Human Health and Disease.

Cholesterol is a sterol, a type of organic compound with the formula C17H28O. It is found in animals and is classified as a zoosterol. In fungi, the mycosterol that performs a similar role to cholesterol is ergosterol.

One way to lower cholesterol levels in the blood and reduce the risk of cardiovascular disease is by taking statins, a class of drugs that act on a pathway that constitutes the first 18 steps of the 37-step process the human body uses to make cholesterol.

Under the influence of ultraviolet light, the body turns cholesterol into calcitriol, an active form of vitamin D made in the kidneys. This process helps ensure that calcium levels are properly maintained in the body.

The human body has a mechanism to recycle cholesterol, beginning with its excretion from the liver and eventual reabsorption into the bloodstream in the small intestine. This helps ensure that we have enough cholesterol for normal bodily function.

Cholesterol plays an important role in brain function as well. Cells called astrocytes make and transport it because it can’t cross the blood-brain barrier directly. This means that any disruption to these cells can lead to serious neurological problems.

Joseph Goldstein, an American biochemist, played a key role in discovering how high levels of cholesterol contribute to heart disease. He shared