|Even if animal fats were the best frying fats, this wouldn't turn doughnuts into "health food" and french fries into raw carrot sticks.|
How on earth could F. Aladedunye, and R. Przybylski, the authors of the previously cited study even dare stating that high-oleic low-linolenic rapeseed, high-oleic sunflower oils are good frying oils?
But enough of the sarcasm: In today's installment of "True or False" (read previous installments) we will focus solely on the cholesterol-containing animal fats, and save the one and only "coconut miracle" (Coconut oil - virgin, of course - must be good for everything, right? There have after all (E)-Books been written about it ;-) for another installment of this series. So, where do we start then? I guess, we could start by rendering down a big packet of butter in my frying pan... but *wtf* what's that? It's turning tar black!? Can that really be the ideal frying fat? Probably not, but if regular butter sucks, what about clarified butter aka "ghee", then? It's easier to process and there are not tarry clouds floating in the pan, when you heat it.
"But don't we all know that cholestrol ain't bad for us?"
Unfortunately, there are other problems with ghee; problems that are related to the heat-induced oxidation of cholesterol and the presence of large amounts of cholesterol oxides in commercially available "clarified butter" even before you even start heating it as it was reported by Kubow et al. in 1993 (12.3% w/w of total sterols).
|If rancid fish full of oxidized PUFA ain't bad for us (read previous article), why would we want to use saturated animal fats for frying then? Please note that the overwhelming evidence says that oxidize PUFAs are bad for you.|
As mentioned before, butter is unfortunately, not the only high cholesterol item on the Internet's list of "best, because highly saturated, frying oils". Next to butter (215mg of cholesterol / 100g) you will also find lard (95mg of cholesterol / 100mg) or tallow (109mg of cholesterol / 100mg) on these lists.
|Figure 1: Even if you believed that cholesterol was bad for you, the ~50% reduction in intact cholesterol that occurs, when you heat tallow at temperatures of 155°C and 190°C should not be a reason to celebrate (Park. 1986a)|
In 1986, a group of researchers who conducted research for the French government found that 78% of the total cholesterol that was lost (23% of total cholesterol) from beef tallow during deep frying was recovered in form of the four best known forms of oxidized cholesterol, i.e. Triol-, 7a-, 7/3-, and 7-Oxo-cholesterol (Bascoul. 1986).
The latter have been shown to decreases barrier function of cultured endothelial cell monolayers (induce leaky gut; Hennig. 1987) and smooth muscle cells (Zwijsen. 1992).
Aside from their previously mentioned effect on the progression of atherosclerosis and their direct effect no the gut lining and other protective barriers in your body. These cholesterol oxidation products (COPs) have also been shown to promote the growth of colon (Kendall. 1992) and other forms of cancer (Sevanian. 1986; Gabitova. 2014), figure in the development of type II diabetes (Mol. 1997), block the production and blood pressure lowering effects of nitric oxide (Brown. 1999) and have been implicated in the development and progression of Alzheimer's disease (AD) and vascular dementia, as well as kidney failure (Sottero. 2009)
|Total amounts of COPs (mg/100g) in the extracted fat of raw, fried w/out and w/ corn, olive and partially hydroge- nated vegetable oil, and steamed salmon (Al-Saghir. 2004).|
|Figure 2: Not all oxysterols are created equal. Those your body creates by enzymatic reactions figure in cholesterol homeostasis (Otaegui-Arrazola. 2010)|
These "good oxysterols" do thus appear(!) to play a subtle but important role in the control of cholesterol homeostasis. In the context of this true or false question, their existence, functions and benefits are however irrelevant. Apropos, question! What's the answer to our question, after all?
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