I think the upshot of much of this research is that sugar and fat aren’t directly the issue. That gut bacteria actually have a much bigger impact on both energy

I think the upshot of much of this research is that sugar and fat aren’t directly the issue. That gut bacteria actually have a much bigger impact on both energy expenditure and appetite than we thought. Insofar as diet has a major effect on obesity (in the epidemic sense we’re seeing in the US) it might be due to diet having a harmful effect on gut bacteria. Or it might not. It’s an intriguing hypothesis, and it’s disappointing to see it devolving into an argument about “not eating too many sweets.”