Cholesterol is a very, very complicated subject. We make it, but it’s also in foods such as dairy products, red meat and processed meat such as sausages. We NEED it [it’s found in the cell membrane of every cell in your body and its required for digestion (because it’s the basis of bile constituents, and bile is necessary for the absorption of certain foodstuffs including some vitamins), as well as being the basis of steroid hormones and vitamin D (which we DO make)].
There’s lots of talk about high density lipoproteins (HDL – ‘good’ cholesterol), intermediate density low density lipoproteins (IDL – so-so) low density lipoproteins (LDL – not so good) and very low density lipoproteins (VLDL very bad). The names come from the relatively crude method of centrifuging blood plasma, which results in separation of these molecules; those right at the bottom are HDL molecules, etc. etc..
There’s less talk of CHYLOMICRONS, but they’re also involved. Eat fatty cheese, wait a while and then take a blood sample, spin it down and the blood plasma (the liquid in which blood cells float) will be opaque because of chylomicrons containing the fat that’s been absorbed from the cheese.
Essentially, because cholesterol is required all over the body, and because it’s not very soluble in blood, it’s taken hither and thither by lipoproteins. Think of them as Uber cars. HDL is good because of where it takes the cholesterol.
When you go to the doctor and have your cholesterol level measured, it will be a measure of total cholesterol, in all the different lipoprotein types. Too much is associated with atheroma formation in blood vessels (see previous posts), and that’s linked to death by heart disease or stroke (aka CEREBROVASCULAR disease – the clue’s in the name).
Sterols and stanols in foods can lower cholesterol A LITTLE because most of the cholesterol in your body is made by you. They work by competing with cholesterol in the diet. STATINS work by lowering your own cholesterol production and are therefore more effective.