Researchers in Malmö, Sweden conducted a blind cross-over trial with 13 healthy adults to see If bread made largely with intact wheat kernels satisfied subjects longer than bread made with whole wheat flour, or refined wheat flour, and how the addition of vinegar would affect satiety. (Acetic acid, or vinegar, is known to increase satiety and lower postprandial blood glucose and insulin response.) The whole-kernel wheat bread with vinegar satisfied longest, even though it had the same amount of fiber as the whole wheat flour bread.
Nutrition Journal, April 27, 2008; 7:12