The study randomly assigned 5,145 overweight or obese people with Type 2 diabetes to either a rigorous diet and exercise regimen or to sessions in which they got general health information. The diet involved 1,200 to 1,500 calories a day for those weighing less than 250 pounds and 1,500 to 1,800 calories a day for those weighing more. The exercise program was at least 175 minutes a week of moderate exercise.

But 11 years after the study began, researchers concluded it was futile to continue -- the two groups had nearly identical rates of heart attacks, strokes and cardiovascular deaths.

Looks like it was caloric-restriction diet. Maybe the next study should put them on a high-fat high-protein low-carb diet and see what happens. Via Diabetes Study Ends Early With a Surprising Result -