"Nicotine is not good for you" is slightly misleading - smoking tobacco is really bad for you, and the reasons for that have nothing to do with nicotine; smoking nicotine free tobacco would be pretty much as bad health-wise.

To the first order of approximation, nicotine addiction is bad for your health because it causes you to burn and inhale plant matter, the common delivery methods of nicotine are horribly unhealthy but if you're talking about nicotine as such (for example, through a transdermal patch) then it doesn't really have significant adverse health effects.

What about chewing tobacco? All smokeless tobacco has risks of cancer. I would not say that nicotine is harmless without a large amount of proof, and it should take about as much proof to say that it is not a carcinogen.

The US surgeon general has a really nice, fucking long, document about tobacco.

Everything in it is evidenced by as much research as they can get.

https://www.surgeongeneral.gov/library/reports/50-years-of-p...

I agree that it's a bad idea to take nicotine in any form unless you need to, but it seems that nicotine is one of the less harmful parts of tobacco.

For chewing tobacco it's probably not the nicotine that's causing cancer, but all the other stuff.

There's actually been a lot of research on nicotine, and the conclusion is that it's _slightly_ carcinogenic.

But more to the point, there was little reason to believe it would cause cancer in the first place, compared to any other random compound. Its association with tobacco is a wash, because other compounds, like aldehydes, are completely sufficient to explain the carcinogenicity of smoking tobacco.

Tobacco is full of really carcinogenic stuff other than nicotine.

For analysis of nicotine as such, you can refer to the known side-effects of nicotine dermal patches; they're well researched, approved by FDA, etc - the place of application can get skin irritation and itchiness; overdose of nicotine can get dizziness, headache, rapid heartbeat, and nausea (same as for too much nicotine through other means), but they're not known to cause cancer or other significant damage despite being used by very many people over very long time.

Nicotine is a neurotoxin. I'm sure it's fine though, as long as you didn't need your neurons anyway.

Weird how it makes you perform better on mental tasks though

Aren't there a lot of drugs which enhance performance in the short term but are harmful in the long term?

That would be a paradox resolution. I suggest to likewise think of the short term effect as harm, so the long term effect is the accumulated harm.

Just like a light hit on the head would increase awareness, but increasing the force and repetition of the hits on the head is not well advised, when the effect wears off after overuse - to say nothing about the immediate effect of getting hit.

The perceived short term benefits are only secondary effects. And with regards to nicotine, all the arguments in favor are to be treated as extraordinary claims.

I wonder how the testing methodology works.

>Nicotine is not good for you.

Nicotine also has benefits - most notably, it is a stimulant. The question is what tradeoffs you are making by consuming nicotine.

https://www.gwern.net/Nicotine

For completeness, one of the issues with e-cigs is that it heats a hydrocarbon by passing it over a poorly-regulated heating element. That's a recipe for creating random organic molecules, many of which are most definitely harmful. Probably not as harmful as old-school smoking, but definitely a case of "do not use around others and do not use except as a substitute for smoking."

can you explain how that's different from toasting bread or roasting vegetables to someone who has a weak understanding of chemistry and what makes molecules harmful?

As someone with a smell allergy, my first approximation to a guess (I am not a chemist), please correct me if I'm mistaken, is something to do with the alcohols contained in most e-cig recipes and borrowed from the perfume industry. Alcohols when aerosolized tend to travel farther than most other smell carriers (that's why perfumes use alcohol) and more directly enter the bloodstream, skipping the body's filters (which makes it particularly useful to e-cigs as a carrier).

I'd suppose other chemicals in traditional cigarettes fill very similar roles.

E-cigs involve direct contact with the heating element at a much higher temperature than food would normally be exposed to. A quick google shows that the element can be as hot as 500F, and the fluid will be in direct contact. Also, the organics used in e-cig fluid are smaller and more easily ripped apart by heat.

Imagine you want your house to smell like coffee. So you heat a baking tray until it is white hot. Then drip coffee onto the tray (don't actually try this). Much of the coffee will be vaporized with the water in it providing a nice aroma. But some of it will be in direct contact with the tray and will burn and have a nasty smell. The hotter the tray is, the more the coffee gets burned and transformed into not-coffee. E-cigs are like that, except one doesn't notice the nasty aroma of the accidental chemicals.

Well, humans have evolved to eat cooked nutrition. We did not evolve to inhale that cooking smoke.

Inhaling stuff is bad for you. Nicotine itself is not terribly different than other stimulants, e.g. caffeine.

> It doesn't look like there's any question as to whether or not e-cigs cause harm, only a question of how much harm

Same goes for almost everything.

I haven't heard much to support nicotine being significantly worse than caffeine.