Both. Even vaping 0mg nicotine is bad for you, but not nearly as bad as smoking.

Has it really been proven that nicotine itself is dangerous?

I'm thinking of articles like https://www.scientificamerican.com/article/is-nicotine-all-b...

I'm obviously talking about moderate doses. I know concentrated nicotine is very toxic :)

Definitely not "proven" to be dangerous, in fact evidence is more compatible with (low dose) nicotine being quite safe.

Best summary I'm aware of (note the many caveats): https://www.gwern.net/Nicotine

What are the health risks of vaping with non-nicotine-containing fluid? I thought that it was just atomized vegetable glycerin with a bit of flavoring, but I've not done much research into the matter.

Personal anecdote: I was never a cigarette smoker, but I started vaping because I tried a friend's vape once and liked it.

I am a pretty serious athlete. Vaping - whether it was 3mg or 0mg e-juice - fucked with my lungs pretty badly, and caused a noticeable drop in athletic performance. Also made me feel way less motivated to lift weights and train, which I chalked up to the instant gratification of nicotine. When I did lift weights and train, I always felt like I wasn't able to give 100%.

I quit, but goddamn it was a pain in the ass to quit. It's not even the nicotine I miss, really, so much as it is the whole experience. The heat, the vapor, the flavor, the habit.

Friends of mine that have switched from smoking cigarettes to vaping e-juice have reported an increase in cardiovascular capacity; but as a non-smoker that started vaping, I definitely noticed decreased performance.

yeah, i definitely noticed that my lungs were better off vaping than smoking but they are certainly not 100% vaping

It's quite hot air in your lungs, and isn't gonna do anything good. Not hot enough to scald you but the interface in alveoli is very sensitive to changes in consistency, thickness and makeup and it'll change how well you can absorb oxygen. Plus it's irritating which can cause inflammation, making it harder to breathe. Not something you'd notice normally but all of that will lower your lung capacity for quite a while.

At super low power it's pretty much totally safe and the impact on breathing is temporary[1]. At ~>18 watts formaldehyde starts to become a possible irritant, and there are also lots of other carbonyls. One of the really fun ones in the graph in [1] is acrolein- it's still at extremely low levels but that shit is not anything you want in your body. It's generated in small amounts any time anything fatty is burned, but absorbing it through your lungs daily is a totally different thing.

Vaping at low power (<20 watts) is pretty safe, but my girlfriends vape goes up to 200 and she uses it constantly at 85 or so. There are definitely significant amounts of chemicals besides glycerine and propylene glycol.

[1]: https://monq.com/vg/

Heating glycerin can produce acrolein and formaldehyde, and this has been reported in ecigs in several studies. The amounts are minuscule compared to cigarettes and don't seem to show up in second-hand vapor, but it's plausible that this could cause some long term harm.

This is why I really wish someone would sell an ultrasonic vape, which the original patent included. That should be far safer, but so far, nobody seems to be making them.

The current concern is metal nanoparticles coming off of the heating coils.

I wonder about this every time I replace a coil that is toasted. There are several types of coils now (Ni, kanthal, stainless) - it'd be nice to know more about the degradation of the metals and its effects for sure.

Kanthal is basically stainless steel with more chromium and a slight amount of aluminum. Which one is better depends heavily on the exact alloys and how they are assembled, unfortunately.

Kanthal requires a very specific heating profile after installation to develop its protective coating. Without that its basically just weird, fancy stainless steel. It becomes very brittle after the heat treat which causes gradual degradation especially during repeated, fast heating cycles. I would not use it.

I would also avoid low-alloy stainless like 400 series. That's the cheapest kind and at elevated temperature it oxidizes and corrodes. 300 series would be better, 500 would be best. Even within those two series though, some alloys will be much better than others.

Nickel... I don't know. It's very sensitive to composition and some can leach into liquid and others don't. It's more toxic than iron or chromium, but pretty resistant to temperature. Kind of a wash.

I don't think nicotine itself is that bad for you, it seems like nicotine inhaled via cigarettes is an entire different league to other nicotine/tobacco forms.

Cigar and pipe smokers as a rule don't have the kind of compulsive many a day habits that cigarette smokers do.

With cigarettes, it's the burning that creates the issue, as the excessive amounts of heat create the carcinogens and the smoke.

It's not just the burning, many toxic chemicals are already present and the processing[1] makes it worse. The processing converts things like nicotine, and happens at relatively low temperatures- lower than those in vaporizers. Plus, keep in mind that nicotine is in tobacco as a poison for insects. Tobacco doesn't want to be consumed by humans either.

[1] https://en.wikipedia.org/wiki/Tobacco-specific_nitrosamines

Chewing tobacco is still carcinogenic.

What in tobacco makes tobacco so bad, compared to all the other plants and animals people chew on?

But perhaps not because of the nicotine.

http://www.medicinenet.com/smokeless_tobacco/article.htm

To me it's unclear whether or not nicotine itself is actually bad.

I haven't said nicotine is carcinogenic.

Lean over an open fire and take a deep breath of the smoke.

I don't think it takes a huge leap to realize inhaling smoke is not good for you.

I might be wrong but I thought the whole point of vaping was you are getting the liquid/material hot enough for it to turn into vapor but not hot enough to burn. Same principle with vaping weed. Sure its not "healthy" but its much healthier than burning. I think your example is extremely wrong.

The whole point of vaping is that there's no smoke.

But vapor isn't smoke.

Vapor is not smoke.