I'm sorry to hear that your daughter is going through this. It's difficult for you as well, I know.

First, you meant that she's 5'6" tall, right? Not 6'6". Depending on how she's built, 140 isn't really that heavy for someone 5'6". It may be cosmetically more than she prefers, but in my opinion it's a mistake to base diet on purely cosmetic considerations, which are way out of whack these days. The "ideal figure" is just too slender for most of us to attain. I would attempt to move her focus away from her looks and onto her health and well-being.

I'd also double-check the amount of protein she's getting. It sounds far too low. There are various ways of estimating a person's protein requirements, but the lowest I calculate for someone weighing 140 pounds is in the neighborhood of 52 grams/day. I would guess that an adolescent needs a fair amount more than that. My method of choice is Protein Power, and here is a direct quote from Michael Eades's website, specifically the page at (http://www.proteinpower.com/drmike/...es-lean-mass/):

" ... let’s take the so-called average person who weighs 70 kg (154 lbs) and calculate daily protein requirements based on the protocol of this study. 70 kg X 1.6 g/kg/day = 112 gm protein per day."

Good luck to both of you.