This is very outdated.
First, I would like to point out that:
Cholesterol is an integral part of EVERY CELL membrane.
Cholesterol is the precursor for progestagens, estrogens and androgens.
Cholesterol is the precursor for glucocorticoids and mineralocorticoids.
Cholesterol is the precursor for Vitamin D.
Cholesterol as antioxidant.
Cholesterol is an essential part of myelin and signal transduction in neurons.
Hence, it is ESSENTIAL, not something we should fear.
Also, when consuming a standard American diet, only about 25% of the cholesterol comes from diet, the rest is made by the body. Meaning if you don't eat it, your body will make it!
The human body is brilliant NOT stupid. We need to change the way we think about this. Thus, if LDL (the so called bad) cholesterol is high there is a reason for it. Either we need hormones, more neurons or there is chronic inflammation. We need to look at the reason. Lowering cholesterol when it is trying to solve a deeper problem is just ignorant!
In fact, here is a large cohort study proving that more than half of the patients with CAD actually had low LDL.
Really good update and great breakdown (and source). This being said most high levels of cholesterol do come from diet and the modern American diet does have too much (though is low in other lipids).
Here is the source for the de novo cholesterol synthesis:
https://www.healthline.com/health/where-is-cholesterol-found
http://www.proofofcare.com/2015/11/what-does-high-cholesterol-do-to-your-body/
These sources do not support my other information though. Again outdated.
I would like to add two more great sources, including the Framingham Heart Study.
In the elderly the higher Cholesterol is associated with better cognition.
https://www.ncbi.nlm.nih.gov/pubmed/15673620
https://www.ncbi.nlm.nih.gov/pubmed/18757771