A small, Israeli study involving 48 overweight and obese older adults with Type 2 diabetes (average age 59) has found that those who ate a large breakfast containing whey protein managed their diabetes better.
Participants in the study were randomly alloted to one of three diets that contained the same number of calories, and followed the pattern: large breakfast, medium-sized lunch and small dinner. They followed this diet for 23 months. The groups varied in the type of breakfast: primarily whey protein; other proteins such as eggs, soy and tuna; a meal high in carbohydrates or starch.
After 12 weeks, the group on whey protein lost the most weight: 7.6 kg (16.7 pounds), compared to 6.1 kg (13.4 pounds) for those on the other proteins, and 3.1 kg (6.8 pounds) for those in the carbohydrate group. Those on whey protein were also more satiated and less hungry throughout the day, with lower glucose spikes after meals compared to the other two diets, and their HbA1C also decreased more than with the other two diets.