Re: Look out
"WRONG. get your facts right. some of your points are 'ok' and the biscuit analogy wasn't bad, but then you went off the rails making claims about nicotine that just are NOT true.
Nicotine exists in some foods. "
You may be right, but your point is completely moot. If he had said "your brain would never have been exposed to in natural life" he would have been a hundred percent correct.
There may be nicotine in vegetables, but there exists a thing called the first-pass effect. Blood-flow from your intestines does not enter the general circulation right away (as blood flow from the lungs does), but goes through the portal vein system through the liver first, where a lot of potentially harmful substances are metabolised first. So any nicotine ingested will be mostly metabolised to cotinine and trans-3'-hydroxycotinine and no nicotine will reach the brain. The levels of nicotine in vegetables are in the orders of nano-grams per gram. So to get as much nicotine in the intestine as a cigarette delivers, one would need to eat a hundred kilos of aubergine. Take in account the oral bio-availability of nicotine and in order to get the same blood levels as from a cigarette, you would need to eat 500 kg of aubergine. I would not call that "being exposed to".
And before someone mentions it: chewing tobacco works mainly through absorption of nicotine through the oral mucosa, which is not plumbed into the portal vein system.
Also not plumbed into the portal vein system is the rectum. Nicotine suppositories, anyone?
Icon: because face-palm becomes fail.