Here are two posts I wrote up on a thread I started on another newsgroup:
Compared to the "studies" you hear about in the mainstream media, this one is excellent:
QUOTE: ...LDL vitamin E levels were highest in rabbits fed corn oil with added cholesterol. The significant elevations in linoleic acid [18:2(n-6)] in serum and LDL may partially explain the high oxidizability of LDL in rabbits fed corn oil. LDL isolated from animals fed corn oil, lard or milk fat had significantly greater albumin transfer across cultured endothelial monolayers compared with those of the low fat diet group. Their oxidative modification further contributed to endothelial barrier dysfunction. Dietary cholesterol supplementation to the corn oil diet decreased oxidizability of LDL and partially protected the oxidized LDL-mediated endothelial cell dysfunction as compared with the corn oil diet group... UNQUOTE.
They found that beef and chicken fat were best, but they did not test any of the highly saturated fat sources, like butter or even better, coconut oil. This is an on-point study because it focuses on LDL oxidation, which begins the heart disease process. Rabbits are more susceptible than people, but the underlying biochemical mechanisms appear to be the same (and there is no alternative to it).
Source: J Nutr. 1995 Aug;125(8):2045-54.Click here to read
http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView...
Moreover, this study is consistent with other molecular-level evidence, for example:
"Cholesterol protects the phospholipid bilayer from oxidative damage."
Source: Free Radic Biol Med. 1995 Oct;19(4):511-6.
http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView...
Just keep in mind that you should not eat foods with a rancid taste, and there is no reason to use high-heat cooking. Boiling eggs is a much better idea than frying, for example. Cholesterol can be oxidized before it gets to your mouth, but if you take precautions, it's unlikely that this will be a problem for you.
Some studies find that highly polyunsaturated oils lower cholesterol, or LDL levels, but if LDL is not oxidized, it's not a problem, and non- oxidized cholesterol, as we've seen, is protective. However, in some of these kinds of studies, the researchers find some disturbing aspects to corn oil-rich diets, such as the following:
"...In contrast [to animals fed lard or palm kernel oil], animals fed the CO [corn oil] diet exhibited a shift of more buoyant to denser LDL particles..."
This is due to oxidative processes, though the authors do not talk about them in the abstract.
Source: Arterioscler Thromb. 1993 Oct;13(10):1418-28.
http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView...
Now for those unwilling or unable to understand the evidence (such as "Ron Peterson," apparently), you have my sympathies, though I do wish you sould stop misleading others. |