Ketogenic diets may or may not provide a metabolic advantage
Findings from a recent Mendelian randomization study have further suggested that reduction in post-prandial plasma insulin levels as achievable by KD (Hall et al., 2016) might be capable of reducing the prevalence of between 1 and 10% of obesity at the population level (Astley et al., 2018). Consistent with this, (Ebbeling et al., 2018a, 2012) reported a “metabolic advantage” of isocaloric carbohydrate restriction that may substantially increase energy expenditure. However, in a widely circulated critical re-analysis by Kevin Hall and Juen Guo available in pre-print (Hall & Guo, 2019), the latest of these findings have been contested on a number of technical grounds. Moreover, as shown by recent meta-analysis, the findings of these studies (Ebbeling et al., 2018b, 2012) are themselves extreme outliers among more than 30 similar controlled feeding studies, which on average show a slight metabolic advantage in fact for low-fat diets (Hall & Guo, 2017).