Is a Breakfast like a King and a Supper like a Pauper good for type 2 diabetes?
A recent paper in Diabetologia adds further evidence that meal pattern and contribution to overall energy (and macronutrient) intake may be of equal importance when deciding what macronutrient profiles are optimal to help with the management of type 2 diabetes. An earlier study published in Diabetologia in 2014 found that following a hypocaloric diet for 12 weeks eating only breakfast and lunch reduced not only body weight but also hepatic fat content and fasting glucose. The current paper has taken this approach a step further.
Jakubowicz et al.[^1] maintained the typical three meal a day pattern but either distributing the energy breakfast: lunch: dinner as 45%:40%:15% for the energy rich breakfast arm, or 15%:40%:45% for the energy rich dinner or evening meal arm to measure acute post prandial effects on the seventh day of following the dietary protocol. The 18 participants followed both diets for 7 days and had a two week washout period in between each. All meals were low fat (<30% energy from fat) and the meals differed also in how much energy they contributed to the total of ~6300Kj (~1500kcal) per day. The smaller meal had a lower percentage energy contributed from carbohydrate of 27% compared to the near 50% for the larger meals, with more energy being contributed from protein (43%). This in part highlights one of the challenges of nutritional research, in that it is possible to match diets for energy, but matching for individual nutrients can be more challenging. So, although any benefits may be attributed to the energy differences, is there also an effect of differing quantities or ratios of individual nutrients?
In this group of people with type 2 diabetes, a mean age of 57 years and a mean Body Mass Index of 28 kg/m2, switching the proportion of energy from evening to morning had the effect of reducing the area under the curve for glucose by 20%, whilst increasing increased GLP-1 levels. This in turn seems to have had the effect of increasing the area under the curve for both insulin and c-peptide. The net effect of enhanced insulin secretion was a reduction in post-prandial glucose levels, which potentially could help in reducing the risk of cardiovascular and other complications associated with type 2 diabetes.
So, what implications does this study have for people with type 2 diabetes? Firstly the evidence and guidelines including those of the American Diabetes Association[^2] and Diabetes UK[^3] for the nutritional management of diabetes suggest that for people with type 2 diabetes with a BMI above 25 kg/m2 (and perhaps lower in some ethnic populations) the principal goal should be weight management. With respect to weight loss, both the caloric intake in the earlier work of Kahleova et al.[^4] and the ~6300kj (1500kCal) per day in this study represent an apparent caloric deficit. However, given the similar caloric deficit in the control arm it should be recognized that the observations were additional to those seen from energy restriction. therefore, this relatively small study supports the idea that changing the energy (and possibly macronutrient) balance of meals, may help to moderate post-prandial glucose excursions. As such, the results from this study suggest that eating breakfast like a king and eating supper like a pauper might be an additional approach for nutritional management of type 2 diabetes, as long as the individual can adhere to such an approach.
Duane Mellor, Section Editor Diet & Nutrition