I am very petite but not even I would survive on 1000 calories per day. That’s a very bad advice because you are making your body to go into emergency “OMG, I’m starving!” mode. And having run a few long runs, I know something about how crap you feel when hypoglycemic.
Avoid or watch your fruit but drink sugary water? How about the nutrients you get from the fruit? The minerals, vitamins? Why deprive yourself of it? I don’t think you are seeing anything else than weight loss but you forget that your body needs other stuff to work properly, such as minerals (magnesium, iron, calcium anyone?) and vitamins (D, E, B, C etc.) and it can get them easily, without taking supplements just by making the right choices when it comes to food. That means eat a piece of fruit or vegetables or both instead of drinking sugary water.
In terms of dietary advice, this one is really bad.