Talk:Cholesterol

In multiple location the page claims that cholesterol is made in all cells, but there is no citation. Furthermore, it is well accepted that neurons do not make cholesterol. And almost all studies show that cholesterol is transported in the blood and then taken up into cells through receptor mediated endocytosis. The mere presence of the enzymes that metabolize cholesterol is not evidence that the cells make cholesterol. Advocates for ubiqitous cholesterol synthesis need to produce evidence that the cholesterol is actually produced in the various cell types rather than taken up.

Lastly, given the large amounts of cholesterol that are taken up by cells from the blood. Some rational as to why the cells would be making cholesterol when there enormous quantities made available every day in the blood needs to be addressed. The data suggests most cells in the body don't make appreciable amounts of cholesterol and the uptake of the cholesterol from the blood or astrocytes dictates the important biological function of cholesterol, not individual cellular synthesis. If there is a biological process known, in a non-hepatic cell, where individual cellular synthesis drives a biological function, please indicate. All the known biological functions of cholesterol, including cholesterol related diseases, is driven by uptake from the blood not synthesis within the affected cells. — Preceding unsigned comment added by PhD2005 (talk • contribs) 03:43, 21 October 2024 (UTC)

Neurons do synthesize cholesterol.^[1][2]. On the other hand, many organisms appear to have lost the ability to synthesize cholesterol through evolution.^[3] Nevertheless, humans definitively do synthesize cholesterol.^[4]

Without even getting into different cell types, most insects can't biosynthesize cholesterol at all. To be clear, they still require sterols, but they must obtain said sterols through their diet.

Here's a review article explaining that most protostomes lack the ability to synthesize cholesterol, not just insects. 198.137.18.219 (talk) 20:05, 6 February 2025 (UTC)

Without any kind of explanation, the article goes from talking about the cholesterol molecule (what this page obviously about) to what people commonly refer to cholesterol in a medical context: the concentration of lipoproteins in the blood.

While there are some historical reasons for that and some influence of one on the other, there is no effort to explain in and the article basically switches to a different topic. IMO, this whole section should be removed and instead discuss the link between hypercholesterolemia and the cholesterol molecule and make the distinction clear.

There is already an article on hypercholesterolemia, and this page reenforces the confusion between cholesterol molecule and lipoproteins like LDL/HDL. Slow.capibara (talk) 05:17, 19 February 2025 (UTC)