What's up with rancid oil

I have heard people talk about rancid oil as if it were poisonous. I understand that it smells bad–hence the name. But when I have tried to locate discussions of it’s dangers, I have largely struck out. My question: Is rancid oil bad for you? What would the consequences of consuming a substantial portion of rancid oil have any dire consequences for my health?

“it’s” shoulda been “its.” Sorry.

If you consume a substantial amount of any oil you will most likely end up with a case of the runs.

Not as bad as poop, but probably higher in cholesterol, and you won’t have much of a chance of being featured in a porn movie for consuming rancid oil.

Rancid oil does impart a particularly nasty flavor to anything you make with it.

I’ve never heard of it being poisonous. However, as previously noted, consuming a “substantial quantity” of oil, rancid or not, will lead to “substantial” gastro-intestinal distress.

Despite how an outside observer may assess your situation, I’d guess that you’d then find the consequences to be “dire.”

http://www.nutritionfarm.com/message%20board/Message_Board/flaxseed2.htm

Rancidness is usually caused by oxidation of the oil. This means more cancer-causing free radicals and a very nasty flavor. Also, it is within the realm of possibility that toxin-producing fungi like Aspergillus flavus could show up, although I doubt the oil is nutritionally complete enough- aflatoxin production is usually associated with raw peanuts or other unprocessed foods.

Aflatoxin is carcinogenic, but not usually deadly (to humans- it kills cows). But if you are thinking of making chips with that funny-smelling oil, I would advise you think again. If nothing else it will taste foul and result in a day-long bathroom stakeout.