Only people with 0 IQ in regards to what your body actually needs to survive would do and advocate that crap.
Doing this is the worst idea ever. Its basicly signing a death sentence.
You need to consume at least 1200 calories a day to make your heart beat. Now add to that you moving around for work or whatever to that, and you'll have what you at least need to eat.
Now, for the proper substance in your diet. Don't eat flippin junk food and think that that is 'food'. It is very low on the things you need (minerals, vitamins, fiber, etc) and high on salt (sodium) greasy fat, refined sugar or artificial sweeteners (mostly found in soda like cola or pepsi but who knows what else they've added them in), pesticides/herbicides (=poisons), and possibly even human remains. There has been a sermon or topic in the past mentioning human flesh being added in meat and sold at MC Donalds or something.
Who knows what other kind of crap is in their food?
The best way to know what you eat, is to make everything from scratch and buy from trusted sources (often locally grown stuff). As for additional supplements, there is a topic on that too.