I know there are a lot of people on this forum that have researched this far more than I have. I also know that we have lots of medical professionals on this board as well. I have some questions that perhaps you folks can answer for me or at least point me towards the answers and share this valuable information with the rest of the group as well.

We all know about the various fasting rituals of a variety of cultures to some degree or another. Of course we all also probably know that there can be serious effects for some people (due to things like low blood sugar) even after a very short time without food.

The infamous 'rule of threes' tells us we can live 3 weeks without food but isn't the key word there "live"??? What serious health risks might we encounter before that magical 3rd weeks has concluded?

With all of this in mind I pose the following question:

With a relatively healthy person... no diabetes or hypoglycemia, etc... what are the physical and/or psychological effects of ingesting absolutely nothing other than water after 3, 7, 14, and 21 days?