>For the first month aka half of the entire study duration. As for "satisfaction" it didn't: diet satisfaction was reported lower in the vegan group. But while

>For the first month aka half of the entire study duration. As for "satisfaction" it didn't: diet satisfaction was reported lower in the vegan group. But while there may have been cheating, we know that the vegan group was consuming less calories, because they lost more weight. If they had been provided the same number of calories, that would tell us that they were cheating less or something similar. Because they were not though, we have no idea how much of it is due to some advantage of the diet vs. the difference in provided meals. The issue is not that this problem disproves advantages of a vegan diet. The problem is it makes it impossible to know. They have hopelessly confounded with a factor that we know is incredibly important in nutrition related health outcomes. And the authors know it too: >Fifth, our study was not designed to be isocaloric; thus, changes to LDL-C cannot be separated from weight loss observed in the study. I personally think that this one throw away sentence is far too small for what is probably the largest methodological issue in the study. Again, this problem doesn't disprove anything about vegan diets, it just makes it nearly impossible to learn anything from this study.