Abstract
The most read article of 2018 published in The BMJ (https://doi.org/10.1136/bmj.k4583) claimed that restricting dietary carbohydrates offers a metabolic advantage to burn more calories and thereby help patients maintain lost weight. However, analyzing the data according to the original pre-registered statistical plan resulted in no statistically significant effects of diet composition on energy expenditure. Furthermore, the large reported diet effects on energy expenditure calculated using the revised analysis plan depended on data from subjects with excessive amounts of unaccounted energy. Adjusting the data to be commensurate with energy conservation resulted in a diet effect that was less than half the value reported in The BMJ paper. Diet adherence is key to sustained weight loss, and no diet has yet demonstrated a clinically meaningful superiority for long-term maintenance of lost weight. More research is required to better understand the factors that sustain healthful diet changes over the long-term.
Footnotes
The revised manuscript corrects the calculations of unaccounted energy.
