This from the NYTimes:
Two years ago, an overweight nutrition professor at Kansas State University went on a diet that was low in calories but consisted mostly of Twinkies and other junk food. In two months, he lost 27 pounds, lowered his bad cholesterol and raised his good cholesterol. His point was that for weight loss, calories mattered more than the actual content of the diet. Twinkie lovers rejoiced, but the nutrition world put its collective head in its hands.