The information in this thread is wrong. There is a difference between fat loss and water loss. At the risk of insulting anyone's intelligence it is important to understand the difference and how they work.
Fat loss or gain is an equation of energy. Your body converts food to energy. Eat more energy than your body uses and you add to fat stores. up the difference. Energy is measured in calories.
No matter what you think now, or what your IP coach told you, or what you read on the internet on in a book or whatever - the above is the only way fat is ever lost. This is a very basic fundamental principle.
Sadly - there is no easy way to measure fat loss or gain over short periods of time so we stand on a scale which measures our weight. Water flux affects the scale in the short run much more than fat loss or gain, especially in women.
The point of this is that you may be losing fat still and the scale may not be reflecting it. If you're following the IP protocol 100% then for sure, you're losing fat. You're just retaining water.
This is very common. Weight loss is rarely linear. People (even very smart ones) use their own experience to determine how to break a "plateau". Common ways you'll read about are to have a "cheat meal", or to change up one's exercise routine, or to eat an extra packet, or mix up one's diet. The truth is, your body is going to release the water it's holding sooner or later and you'll experience a "whoosh" whether you change anything or not.
Good article on the subject.