Thanks for the links and your answers. It seems from your answers as if
shortening could come from either animal fat or veggie fat. The text of Mary
Enig which roused the question for me is below. It seemed to make a big
difference if they used "Wesson oil" or "shortening" together with
cholesterol; that's why I wondered.

http://www.westonaprice.org/know_your_fats/oiling4.html

"Actually the controversy dates back to 1954. In the rabbit studies that
launched Kritchevsky on his career, the researcher actually found that
cholesterol fed with Wesson oil "markedly accelerated" the development of
cholesterol-containing low-density lipoproteins; and cholesterol fed with
shortening gave cholesterol levels twice as high as cholesterol fed alone.65
Enig's work-and that of Kummerow and Mann and several others-merely
confirmed what Kritchevsky ascertained decades ago but declined to
publicize, that vegetable oils, and particularly partially hydrogenated
vegetable oils, are bad news. "





> According to Mary Enig in Know Your Fats: "Shortening is the term used
> to designate a fat in its anhydrous form
>Technically margarine is not shortening.