I want to talk about that fascinating @davidludwigmd study, finding that people on low-carb diets burned more calories during weight maintenance after weight loss than people on high-carb diets. nytimes.com/2018/11/14/wel…
The people on the low-carb diet burned about 200 calories more per day than the people on the high-carb diet (mid-carb was in between). bmj.com/content/363/bm… 
So the first question is: did those people lose more weight? If they're burning 200 cals/day more over 20 weeks, you'd think they would. Or at least they'd have an easier time maintaining. But no. Neither of those things happened.
Why not? Well, for starters it turned out that the low-carb folks ate more. About 130 calories more per day. This, despite the fact that diets were carefully prescribed to be the right amount for weight maintenance.
Also, we don't know why the low-carbers burned more. It wasn't because their resting energy went up, and it wasn't because their activity went up. There are other things it could be, but we're guessing.
The other issue is the accuracy of doubly-labeled water as a measurement of total energy expenditure, but I don't begin to understand that and sure wish somebody who does could explain it for the class.
So, bottom line. Super interesting finding. But if low-carbers burn more energy, but it doesn't help them either maintain their weight loss or lose more weight, it's of limited utility. THE END
