TUESDAY, Feb. 24, 2015 (HealthDay News) -- Eating a big breakfast but a light dinner may help people with type 2 diabetes keep their blood sugar in check, a small trial hints.
The study of 18 adults with type 2 diabetes found that people had lower blood sugar levels on days where breakfast was their biggest meal and dinner the lightest. On average, their blood sugar levels after meals were 20 percent lower, versus days where they had a small breakfast and feasted in the evening.
But before people with diabetes start hitting the all-you-can-eat breakfast buffet, there are big caveats, experts said.
First, the study looked at blood-sugar effects over just one week. "Now we need to demonstrate that the meal schedule with a high-calorie breakfast and reduced dinner works in the long term -- three or six months," said lead researcher Dr. Daniela Jakubowicz, of Tel Aviv University in Israel.
Plus, the diets in this study were carefully controlled, with each meal having a particular balance of carbohydrates, protein and fat. The overall calorie intake was also capped at about 1,500 calories for the day.
According to Jakubowicz, the same principle should hold even if people ate more daily calories. A proportionately big breakfast and small dinner could still help with blood-sugar control.
But other researchers who reviewed the study pointed to some obstacles in bringing this diet into the real world. One is practicality.
"If most people were still farmers, this would be natural," said Judith Wylie-Rosett, head of health promotion and nutrition research at Albert Einstein College of Medicine in New York City.
In today's society, people are often in a rush in the morning, Wylie-Rosett noted. "A lot of people skip breakfast altogether, and then load up at dinner," she said.
This study, according to Wylie-Rosett, does reinforce something that research -- and conventional wisdom -- hold true: Bypassing breakfast is probably unwise.
And while sitting down to a feast every morning might not be feasible, people with diabetes may still benefit from less dramatic changes, Wylie-Rosett said.
"I think it's reasonable for people to at least eat some breakfast, and a smaller dinner," she said. "And smaller changes are often easier to maintain over time."
For the study, Jakubowicz and her team had each of their participants spend two weeks on a controlled diet. They were given the same "large" and "small" meals each day, with the same lunch in between. The only thing that changed was the timing. For one week, people ate their large meal in the morning and the small meal at night. During the other week, they reversed that pattern.
The small meal was around 200 calories, consisting of salad, three slices of turkey breast and a cup of coffee.
Lunch was always the second-largest meal of the day, at about 600 calories. It included a salad with olive oil, vegetable soup, roasted chicken, a baked potato and an apple.
For their large meal, participants were allotted 700 calories -- one scrambled egg, some olive oil and tuna, two slices of whole wheat bread, yogurt and cereal, a granola bar and a latte with nonfat milk.
And therein lies another issue with bringing this to the real world, according to Dr. Osama Hamdy, medical director of the obesity clinical program at the Joslin Diabetes Center in Boston.
"This is not what breakfast looks like for most people," he said.
To most Americans, the phrase "big breakfast" probably conjures up images of pancakes smothered in syrup, buttered toast and a pile of bacon. But these findings do not give a green light to that kind of eating, Hamdy cautioned.
He said it would be more helpful to study the blood-sugar effects of meals that are more similar to the "way people really eat."
"From a clinical perspective, translating this [study] diet to the real world would be nearly impossible," Hamdy said.
Beyond that, it's not clear how effective the big breakfast/small dinner schedule really is. The study participants' blood sugar levels were measured shortly after each meal. Hamdy said that does not give a true indication of longer-term blood-sugar control.
Hamdy agreed that eating breakfast -- with some protein -- is a healthy idea. But he cautioned against seeing a big breakfast as the "magic bullet" for type 2 diabetes management.
The findings were published online Feb. 24 in the journal Diabetologia.
More information
The American Diabetes Association has more on meal planning.
