Are the saturated fats that are found in plants, such as palm oil and cottonseed oil, molecularly identical to the saturated fats that are produced in animals?
Are the health consequences of consuming these the same?
Thanks.
Yes, they are. But they’re not. Sort of. According to the 548-page chemistry textbook I just happened to have on my desk (thank you, chemistry revision!), most common fats and oils contain a mixture of fatty acids such as lauric, myristic, palmitic and stearic acids, which are the saturated fats, and oleic, linoleic and linolenic acid, which are unsaturated. The difference between plant oils and animal oils is which of these fatty acids they contain.
Now, you mentioned palm oil and cottonseed oil. My book does not say anything about palm oil but according to this here chart cottonseed oil is approximately 1% myristic, 20% palmitic, 1% stearic, 20% oleic and 55% linoleic. Compare this to butter which is typically 4% lauric, 12 % myristic, 28% palmitic, 10% stearic and 26% oleic. That’s 54% saturated fat compared to cottonseed oil which is only 22%. That’s still high enough that I wouldn’t recommend you consume large quantities of the stuff but you can probably see the difference. Margarine, incidentally, must have a saturated fat content lower than 20%.
The thing is, if you went and isolated the different fatty acids within oils then there would be no distinction between “plant fat” and “animal fat”, only saturated and unsaturated. When people say plant fats are better than animal fats it is because plant oils generally contain less saturated fat than animal oils. If you decided, for instance, to start spreading solidified palmitic acid on your toast every morning it would be massively unhealthy regardless of whether it orginally came from a plant or an animal. I also notice from this chart that coconut oil is 46% lauric acid, a saturated fat, so just coming from plants won’t really guarantee that something is healthy, assuming that lauric acid is indeed bad for you. I think I will stop talking now before a make a huge blunder. Maybe soon someone who has a proper understanding of these things will come along instead of a chemistry student who is merely reading out of her textbook and making happily ignorant inferences.
Just a point of clarification: you should be aware that the saturated fats produced in animals are very different to the saturated fats found in animals. When you eat animals you may be largely eating fats that were not produced by the animal.
Animals can produce fats from carbohydrates and even protein isf they are able to get eces energy form those sources. However that’s a pretty expensive process, so animals preferentially produce fat fom the fat they eat. Fats are unusual amongst animal foods int hat the body doesn’t break them down much during digestion. Things like proteins and carbohydrates largeley need to be broken down in constituent monomers in order to enter thebloodstream. However because they are fat soluble (duh) fats can enter the bloodstream across the gut wall intact.
So what we have is a situation where fats eaten in food enter the bloodstream largely unaltered, and where aft laid down by an animal is preferentially formed by fat eaten in the food. What that means is that when an animal eats saturated plant fats it tends to deposit saturated plant fats. These fats are not only identical to the original plant fats, they quite literally are the plant fats. The exact same lipid molecule found in the peanut or cocounut is deposited in the animal’s fat cells.
This can become problematic with animals like pigs if they are fed large amounts of unsatutrated fats. Because the fats are laid down unaltered the fat of the animal becomes oily and sloppy, which is undesirable. As a result pig food tends to be pretty high in saturated fats.
In ruminants the probem is less severe, and the fats produced are usualy very different to the original plant food. that’s because ruminants rely on fermentation of food in the sotmach before it is absorbed. Any fats are fermented and chemically altered by the gut flora, and the flora are then digested. So the fat found in ruminant flesh is usually very difefrent in composition to the plant food they are consuming.
If they are molecularly identical then the health consequences will be the same of course. The body can’t differentiate between molecules based on past history. However animal and plant saturated fats are quite often different molecules and can have very different properties.
[nitpick] I am sure you know, but fats are of course triglygeride esters of fatty acids, not the acids themselves [/nitpick]
No, I didn’t know that. I was hoping I’d stopped talking before it became clear I didn’t have a clue what I was on about.
… but now I know, thanks. Did I sound angry?
of course not 
wipes brow and runs for the hills
Just a side question (naive ?): Is there a difference between butter fat and actual animal fat found e.g. in ground meat ?
Wanna hear something else that’s interesting?
Cholesterol is manufactured in a liver.
If what you’re eating doesn’t have a liver, then it does not contain cholesterol, regardless of the fat content.
This is why vegetable oil doesn’t contain cholesterol – vegetables don’t have livers.
Sorry, but that is completely untrue. All animals produce cholesterol, and that extends all the way back the sponges and jellyfish, which certainly lack anything even remotely like a liver. There are many microbes that also produce cholesterol, and being single-celled they obviously lack a liver.
Vegetables contain no cholesterol because plants can’t produce cholesterol. It’s got nothing to do with having a liver, even if plants had aliver they couldn’t produce cholesterol. Animals can and do produce cholesterol and so all animal products conatin cholesterol regardless of whether the animal has a liver or not.
Furthermore, while they can’t produce cholesterol, plants can produce other sterols. Soybeans produce enough sterols to be commercially useful in cosmetics.