The reason that I see is because of yeast, that is what would cause a stall and why you would cut out things like mushrooms, cheese, and sour cream, etc. Here's a link to some informaiton about it:

http://atkins.com/Archive/2001/11/28-709329.html

"However, if you do have a yeast overgrowth, there is another category of food that you will need to avoid: yeast- and mold-containing foods. This includes cheese (except for mozzarella and cream cheese), vinegar, soy sauce and other fermented condiments, plus mushrooms, sauerkraut, sour cream, peanuts, cashews and pistachios (all nuts are subject to mold, but these last two often contain the greatest amount). The list also includes smoked or cured foods, yeast-containing vitamins (make sure the label says they are yeast-free) and wine, beer and spirits."

"It is important to remember that yeast overgrowth stresses the immune system, undermining your total health. When it comes to weight loss, a yeast overgrowth in combination with mold sensitivity may lead to a suppressed metabolism. This may deplete your body of the energy it takes to burn fat. Of course, there may well be other causes that have not yet been identified. Researchers and doctors still don't fully understand what candida overgrowth does to the human body."