Yeah, it gets back to the question of, "what caused the difference: was it what they ate, or what they *didn't* eat?"

>>"eating whole-grain foods, especially fiber-rich cereals, appears to improve insulin sensitivity and lower the risk of the metabolic syndrome. "

This is the part I have a problem with. What the study said (from what I understand) is that people who *habitually* ate more whole grains had less metabolic syndrome than people who didn't. This probably means the latter group ate more refined grains and sugar. It's a little inaccurate to conclude that whole grains will *improve* insulin sensitivity.