This is part of a review I posted on Amazon for "Muscle Myths: 50 Health & Fitness Mistakes You Don't Know You're Making:"
There is new research now that certain foods heavily influence your gut bacteria, and that the type of gut bacteria you have has a lot to do with your weight.
Actual scientific studies, published in Nature, show that the obese patients in the study (about 80% of the group studied) had lower counts of gut microbiota. These people were more obese than those with higher counts of gut bacteria. They also tended to put on weight faster.
If a calorie is just a calorie, then nobody in the groups should have put on weight unless they were eating more calories than they were burning. So it seems that there is more to it than just calories in vs. energy expended. Hmmm.
I highly recommend getting a copy of Dave Asprey's "Bulletproof Diet" and "Go Wild: Free Your Body and Mind from the Afflictions of Civilization," by John J. Ratey and Richard Manning. Both books go beyond the calorie. The types of food you eat do influence gut bacteria, and these books explain that very well.