You have to be so careful what you find out there on the web. There is no possible way that grape juice will help the digestive tract become slippery to expel the yeast. The yeast once it has gone into overgrowth has "rooted" into the intestinal walls and that is what causes us to have symptoms and diseases. I have read The Yeast Syndrome and The Fungus Link and watch Doug Kauffman, author of the Fungus Link and along with curezone they all back up the theory (and actually this is proven stuff) you can't get rid of candida overgrowth easily, it takes time, perseverance, will power and even prescribed and or over the counter treatments.
I agree with the person who said they'd be scared of all the sugar. I would be too. To get rid of candida the first thing one has to do is clean up their diet by getting rid of all carbohydrates, this means all baked goods, flours, sugars, rice, pasta, potatoes, peas, legumes (lima beans, navy beans, pinto beans, refried beans etc.), corn basically anything that is an American standard LOL. There are also other things you need to avoid like aged cheeses (they have mold), mushrooms, vinegar, pickles and other things that are prepared with vinegar. Condiments like ketchup, tarter sauce, miracle whip anything that is sweetened. Doug Kauffman also does not recommend eating peanuts because of a mold that can grow on them call afatoxin, it is a carcinogenic mold, it also is partial to corn as well so he suggests always avoiding these two foods.
If you can get a doctor to prescribe, he always recommends taking nystatin and diflucan, but if your Dr won't cooperate (as many don't) you can take many natural things, just be sure to rotate them in a 4 - 7 day cycle. Grapefruit seed extract, caprylic acid (a personal favorite of mine), olive leaf extract, Pao D'Arco tea and many other things.
Hope this helps give you a little more insight into ridding the body of yeast.