I will just say from my point of view that it has been a total science experiment.
For years I did all the fad diets, lost, gained, lost, gained.
Then I joined Fitday, Since January I have logged every single thing. I find that if I ate lower than 1400 calories my body held on to every calorie it could. If I eat more than 1600 I gain. Then to top it all off if I eat the same calories everyday I don't do much either, I have to calorie cycle. One day I eat 1100 next day I eat 1700 and so on. So to make this long post short.
You have to experiment, every single person is different and the body is a science experiment unto itself. It is a ton of work but now I can take that knowledge and work with it.
Highest weight October 1st, 2011 247.6
Starting weight January 3rd, 2012 227.8
January pounds lost 7.8 = 220
February pounds lost 4.4 = 215.6
March pounds lost 2.6 = 213 (do better in April)
Goal weight 160.4