:: the stubborn fat cells theory - by mum ::

I was talking to my Mum yesterday. As usual, she asked if my weight changed. I told her it was holding steady at 159. She offered a theory that after significant weight loss, once needs to maintain the weight for 6 months before additional weight can be lost. She suggested that I'm going through a phase now that the fat cells are resisting the changes and wants to go back to their "old ways". So I have to keep fighting them until they "give up".

Is there any truth in this theory or is this just like the time she told me that I must eat more mushrooms to make my hair grow faster?