|Time for carbs, or time for protein? Not really a useful question, as a closer analysis of a recent study shows.|
Why? Well, the conclusion of the study, which investigated the effects of macronutrient timing on on body weight and composition, energy metabolism, and biochemical markers in overweight/obese men, speaks of increased dietary thermogenesis of eating carbs at night and a negative impact of eating protein mostly at dinner and carbohydrates at lunch on glucose management.
What is actually interesting is not what happened, when the scientists messed with the diets of their 18-45 year-old subjects with body mass indexes ranging from chubby 26kg/m² to obese 35 kg/m² and stable weight (±3 kg) during the previous 3 months, though. What is interesting is what happened, when they were eating mixed meals like any sane individual that has not been infected by the Internet "macronutrient timing" virus.
|Figure 1: Detailed breakdown of the macronutrient composition of lunch and dinner in the three intervention group; relative energy and total macronutrient content were identical (Alves. 2014)|
Don't fall for what the abstract suggests
Now the initially mentioned conclusion in the abstract on pubmed and elsewhere suggests that it would be beneficial to postpone your carbohydrate intake to the evening hours. I mean, an increase in DIT (=dietary thermogenesis) sounds great and the absence of the nasty ups and downs of the glucose metabolism in the DPNC group certainly ain't bad, either. So why shouldn't we eat all our protein at lunch and the carbs at night?
Well, the reason is easy. The abstract does not mention the most important observation: The fact that the control diet was superior in the practically all relevant study outcomes. So, the increase in DIT as nice as it may sound - What is it worth, if it does not translate in increased fat loss?
|Figure 2: Changes in body composition and glucose & lipid management (Alves. 2014)|
- Alves, Raquel Duarte Moreira, et al. "Eating carbohydrate mostly at lunch and protein mostly at dinner within a covert hypocaloric diet influences morning glucose homeostasis in overweight/obese men." European journal of nutrition 53.1 (2014): 49-60.