Type 2 diabetics and everybody else gets told that breakfast is the most important meal of the day. The problem for Type 2 diabetics is that breakfast is also often the biggest meal of the day. People with diabetes wake up in the morning ready to eat eggs, sausages, cereal, doughnuts, potatoes, juice, tomatoes, ready to eat everything in sight. But there is a way to fight off morning cravings.

Dr. Karen R. Kelly of the Cleveland Clinic in Ohio in the United States tried an experiment with 17 diabetic volunteers, all of them between 65 and 67 years old. Keeping all the volunteers on a constant-calorie diet (that is no additional food, but no weight loss dieting either), Dr. Kelly assigned:

9 volunteers to eat a high-glycemic index diet, averaging over 80, and
8 volunteers to eat a low-glycemic index diet, averaging below 40

• A high-glycemic index diet includes potatoes, bread, rice, sweets, and breakfast cereals, although not in unlimited quantities. Remember, these test subjects did not get to eat extra calories.

• A low-glycemic index diet eliminates potatoes, bread, rice, sweets, and breakfast cereals, and really does not leave a lot of room for fruit. There can be small servings of fruit, maybe a single piece of candy every few days, and so on, but mostly the diet is high-protein, low-fat foods plus vegetables.

All the volunteers were assigned to an exercise program 1 hour a day, 5 days a week. Remarkably, (this is actually rare in exercise programs), the participants lost an average of 16.7 pounds (7.6 kg), some as much as 3 pounds (1.5kg) more, and some as much as 3 pounds or 1.5 kgs less! But all the participants lost weight by doing exercise, because they did not consume more calories.

This study shows Type 2 diabetics actually can lose weight eating the “wrong” foods if they just exercise and do not eat too much. But the volunteers who ate the high-glycemic index diet found that to be a lot harder to do. Dr. Kelly looked for the underlying reason why.

There is something about eating foods that are low on the glycemic index that reduces secretion of the hormone GLP-1, also known as glucagon-like peptide-1. This is the hormone the small intestine secretes when there’s digested food inside. It signals the pancreas to release insulin to transport sugar and store fat. It also tells your stomach that its work is done and you are ready for more.

Because the volunteers in both groups limited the amount of food they ate, they did not have high blood sugars and they also lost weight. But the people in the high-glycemic index group made more GLP-1. Their stomachs got the signal, “OK, fill me up again,” and it was especially strong in the morning. This study tells us that if you don’t want to wake up hungry and stay hungry all day, eat vegetables, low-glycemic index fruits, and protein foods.