I wonder why that is. The key point is "voluntary" starvation, read fasting. Why not make a study with consenting participants to fast for a specific time? Which "clear ethical barrier" is broken here?
It also may put pressure on them to continue where they normally would have stopped because they feel pressure because “those scientists invested so much time in it”.
And of course, they may suffer long term health effects, even if they fast for a period that typically doesn’t have any on subjects.
You can see these kinds of ethical issues clearer by exaggerating. Replace “fasting” by “being hit in the face”, for example. What’s wrong with looking for volunteers who want to be hit in the face every hour for weeks?
People when watched behave different. People under contract behave different.
It is one thing to take notes when someone does this voluntarily. It is quite another to put people under contract for something like this.
I am under the close supervision of my 30 old son and have been since he was 13. It's a completely different dynamic than reporting results to a doctor or lab for a study.
As noted by another poster, extreme fasting is sometimes fatal.[0] I've also heard elsewhere that it can be fatal and a physician should be consulted before fasting more than a couple of days.
Dr. Jason Fung [1] has some fascinating videos on Youtube about why fasting isn't bad. I am just curious why there's a mainstream view that it's bad and the exception is that it's good, vs the other way around?
[0] http://www.nbcnews.com/id/16614865/ns/us_news-life/t/woman-d...
[1] https://www.youtube.com/watch?v=v9Aw0P7GjHE https://www.youtube.com/watch?v=tIuj-oMN-Fk
Edit: Dr. Fung points out one common misconception that fasting causes muscle to be eroded.
When I was in middle school, I remember my friend's older sister being on some kind of snack diet that was supposed to keep metabolism high by never going more than an hour or so without food when not sleeping.
I seem to remember Brad Pilon in "Eat Stop Eat" briefly mentioning the origin of the myth that your metabolism tanks rapidly if you skip a meal, but I could be wrong.
I do intermittent fasting myself, and it drives me a little crazy when my wife tries to convince me that it's bad for my health to skip dinner once in a while on one of my non-fast days.