We know to multiple decimal places what a lifetime of regular caffeine intake in the form of coffee or tea will do to a person (not much, with the health benefits mildly outweighing any negatives) whereas no one has ever spent the bulk of their lifetime using this kind of brain stimulation regularly.
It may very well be harmless or even long-term beneficial. Or not. The only way to really tell is to perform the experiment, and as usual the early adopters will be taking the risks for the rest of us.
I'm excited for the possibilities here, but I'm in no hurry to be a guinea pig.
Most of the data is of the kind "people who drink moderate amounts of coffee show lower $BAD and/or higher $GOOD", so it isn't enormously compelling on the benefits (could easily be some confounding population characteristics despite attempts to get good controls) but is pretty compelling on the lack of harms.
Tea data are similar but quite a bit weaker. Can't find any sources but WebMD is reputable and has a nice summary: http://www.webmd.com/diet/features/tea-types-and-their-healt...
There is at least some biochemical justification for the belief that coffee and tea are good for us--they contain things that are thought to have positive effects--but the chemistry is complicated and not well-understood.
And since humans are omnivorous hunter-gather-scavengers we are able to eat pretty much anything and still stay moderately healthy, so any strong claims relating diet and health are pretty close to Creationism: for humans to have a narrow, deep dietary optimum would have required our ancestors to be selected by processes that produced such a thing, and the life of omnivorous hunter-gather-scavengers is pretty much the opposite of that.
It gets a bad rep because of the existence of involuntary treatments. That doesn't mean that there are people that consent to it, because it can be highly beneficial to specific types of psychiatric illnesses.
As far as I've understood from a doctor friend that explained it to me, the patient is fully under narcosis and paralysed (otherwise the muscles will do all sorts of dangerous things), so they don't notice a thing, apart from probably waking up with a sore arm. This is because (I've been told) they leave one arm not paralysed for feedback and monitoring the process.
See Wikipedia for more info:
ECT has been construed poorly in the media, typically as abusive towards patients (or as a threat). However, it's a legitimate technique that's been proven in clinical trials repeatedly. In popular lit, you can read about the experience of going through (and receiving help from) ECT in Sylvia Plath's The Bell Jar; I've personally experienced a thorough ECT treatment, and her depiction of the relief (the titular bell jar imprisoning her/suffocating her is lifted to sweet relief).
Medically, it's introducing small (but seizure-inducing) voltages to the brain. The patient is typically given a muscle relaxant and/or a sedative for the duration of the administration. They are tied down—not to stop the patient from resisting, but to stop them from hurting themselves during the administration through involuntary muscle movements. This is repeated, multiple times in a week, for several weeks until being able to discern either a positive effect or lack thereof.
When I last researched, it was not entirely understood why this treatment provides such a fundamental relief. One theory (I tend to hold this one, as it just makes sense) is that some peoples' depression emerges from an overconnected brain, seeing patterns and associations that others do not (as easily). Under this model, the ECT severs some portion these connections and brings "quiet" to the depressed person's brain; again, this is similar to what I have personally observed in myself.
I should note, the ECT is a serious treatment with long-term neurological effects. Short-term memory loss is common, with other complications being much more rare. It should not be taken lightly as it can cause perceptible, permanent changes to the person's emotions, memory, personality, and cognitive ability, with by far the largest symptom being impairment of short-term memory.
I know someone who had this treatment for extremely severe depression and it worked remarkably well. Short-term memory loss is a common side effect, but it doesn't last.
Caffeine and alcohol have horrible side effects on my mind, and my body. I didn't realize for years, about the caffeine. I don't know about this kind of electrical stimulation. The fear that I wouldn't have the predictable kind of control over the growth and direction of my neural connections doesn't sound like something I want. I tend to think of these things in terms of trade-offs though.
I personally do not think it is very intelligent to place control over a highly sophisticated organ in the hands (or brain) of another being, unless I am certain to trust that being in that they know what they are doing. Very generally, it just seems like allowing someone else to manipulate, shape, and mold my mind, without me having a choice over it. I don't know if that is paranoia, or a kind of 'survival of the mentally fittest'.
I know that when I feel like it is highly probable that I have been duped into thinking a certain way because someone else thinks it better for me, and I find out that they intended to do this, there is a certain kind of rage that manifests in me, that is unlike any other. It begins with the assumption that they thought they were more intelligent than me. I've thankfully never been proven correct on this, but I tend to disconnect from people that don't have the ability to maintain a constant of mental equality throughout interaction. This is fairly tangential to the topic, but I think it's somewhat relevant in a broader context of the potential consequences of science poking at the brain, without understanding how the brain might fight back.
I remember a time when there was always somebody telling me what was good for me, making me write essays about things that didn't seem relevant, etc.; It lasted for years, and yes, it has shaped my mind.
I practice what I call 'conceptual destruction', where I identify the foundational elements of a thought process, and I practice thinking without being able to use them. It can sometimes be difficult, but my ultimate goal is to have a sharp, stable, quick, flexible, cautious, careful, discerning, and so on, mind, that I created myself. I don't know if I am fooling myself half the time with things my mind does anyway without my explicit direction, but I like having a vast, partially independently established, pedantically defined and carefully organized system for 'ways of thinking'.
It's the only thing I really truly care about maintaining myself: having the capacity to condition myself, and having the intuition to be able to detect and identify when someone is trying to do it for me, or something is doing it for me by chance. I don't like having to depend on culture for how to think, I want to be able to know how to think on my own. It just makes the world less scary for me; it's an ability to rely on myself.
I don't dispute anything of what you're saying in itself, but if you mean to imply that it's hard to go wrong with direct current stimulation to the brain because the currents are much smaller than what's needed to drive household appliances, I'm highly skeptical of that claim.
I was shocked with it dozens of times, we all were, and only once did it really hurt. I couldn't walk for a few hours. For some reason my left leg went numb and didn't feel right.
Boys will be boys.