As discussed in Part I, blood cholesterol levels can be affected by the intake of various fats. The other factor impacting blood cholesterol levels is the cholesterol absorption in the body. Blocking cholesterol absorption in the body is the basis of statins, and statins are effective at lowering cholesterol, their side effects notwithstanding. But for those of us wanting to go the natural route in lowering cholesterol absoption, there is another method - plant sterols.
Plant sterols are a natural substance found in various plant foods. Here is a great paper that reviews plant sterols and their effect on blood cholesterol levels. It points out that "plant sterols were briefly used in the reduction of blood cholesterol levels before the introduction of pharmacological agents". Therefore, in a sense plant sterols were a precursor to modern array of statins. This review also shows that plant sterols are effective at blocking cholesterol absoption and lowering LDL cholesterol levels.
For a person wanting to increase their intake of plant sterols, they could simply eat more plant food. But you have to eat a great deal of plant food just to get a few grams of plant sterols. An easier method might be to use a modern product like Benecol, which is a butter substitute that contains plant sterols. Of course, there are other benefits to eating plant foods besides just plant sterols, and a person will miss out on these benefits by eating little plant food and just the plant sterols. But the sterols by themselves are still effective at lowering cholesterol.
Another newer option is to consumer plant sterol in a supplement pill form. A recent study shows that plant sterols in pill form are equally effective.
Tieing all this together, you can see that a hunter-gatherer diet would naturally lead to low blood cholesterol levels. First, they ate a diet that even though it was high in fat, contained low saturated fat and no trans fat. Second, they did consume a good deal of dietary cholesterol, but as I've shown this only has a small impact on blood cholesterol levels. Third, they ate a large amount of plant food, which provided the plant sterols which helped to block cholesterol absoption.
Hunter-gatherers had total cholesterol levels around 120. I think Loren Cordain has show pretty convincingly ( papers #28 and #34 ) that lower LDL cholesterol, in the range of 30 to 70, is optimal. The current cholesterol guidelines need to be revised downward, and with the appropriate dietary changes and supplements, blood cholesterol levels can be lowered to these healthy levels.