Eating a big breakfast rather than a large dinner may prevent obesity and high blood sugar,
according to researchers from the University of Lübeck, Germany, who investigated whether there is daytime time variation in diet-induced thermogenesis (DIT).
Our body expends energy when we digest food for the absorption, digestion, transport and storage of nutrients. This process, known as DIT, is a measure of how well our metabolism is working, and can differ depending on mealtime. However, it is unclear whether a potential diurnal variation in DIT is preserved during hypocaloric nutrition.
The researchers hypothesised that DIT varies depending on the time of day and explored whether this physiological regulation is preserved after low-calorie compared with high-calorie intake. The outcomes are reported in the paper, ‘Twice as High Diet-Induced Thermogenesis After Breakfast Versus Dinner on High Calorie as Well as Low-Calorie Meals’, published online in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.
“Our results show that a meal eaten for breakfast, regardless of the amount of calories it contains, creates twice as high diet-induced thermogenesis as the same meal consumed for dinner,” said Dr Juliane Richter from the University of Lübeck, Germany, and the study's corresponding author. “This finding is significant for all people as it underlines the value of eating enough at breakfast."
Under blinded conditions, 16 normal-weight men twice underwent a three-day in-laboratory, randomizsd, crossover study. Volunteers consumed a predetermined low-calorie breakfast (11% of individual daily kilocalorie requirement) and high-calorie dinner (69%) in one condition and vice versa in the other. DIT was measured by indirect calorimetry, parameters of glucose metabolism were determined, and hunger and appetite for sweets were rated on a scale. They found identical calorie consumption led to 2.5 times higher DIT in the morning than in the evening after high-calorie and low-calorie meals (p<0.001). The food-induced increase of blood sugar and insulin concentrations was diminished after breakfast compared with dinner (p<0.001) The results also show eating a low-calorie breakfast increased appetite (p<0.001), specifically for sweets (p=0.007), in the course of the day.
“DIT is clearly higher in the morning than in the evening, irrespective of the consumed calorie amount; that is, this physiological rhythmicity is preserved during hypocaloric nutrition,” the authors concluded. “Extensive breakfasting should therefore be preferred over large dinner meals to prevent obesity and high blood glucose peaks even under conditions of a hypocaloric diet.”
"We recommend that patients with obesity as well as healthy people eat a large breakfast rather than a large dinner to reduce body weight and prevent metabolic diseases," added Richter.
Co-authors include Nina Herzog, Simon Janka, Thalke Baumann, Alina Kistenmacher and Kerstin M Oltmanns of the University of Lübeck.
The study was supported by the German Research Foundation.