Here is the link to the open access article.
It’s an interesting study that many here are missing the details. It’s not a no meat diet but avoiding things like ground beef and having a steak instead. It’s not avoiding carbohydrates, but it’s replacing things like: puffed rice cereals, fruit juices, sugary drinks, American cheese, and vanilla wafers, with things that are high in resistant starch like: nuts, beans, lentils, brown rice, quinoa, etc.; and they made a distinction that things are not ground for the healthy versus unhealthy diet. This means, no nut butters or ground oat flour, etc.
The whole study hypothesis is food that is digested further in the digestive tract and can reach the intestinal bacteria is far healthier than food that is digested in the stomach and upper GI tract. What they found is far more calories are absorbed by the easy digestion food, with almost 100% of calories being absorbed. Whereas the food that doesn’t get digested until the lower GI tract have few calories absorbed by the human, more calories absorbed by bacteria, and the bacteria population grows with more healthy bacteria. These bacteria in turn produce a lot of healthy short chain fatty acids which are known healthy fats for both the vascular system and brain plasticity.
It really is a big deal because it is one of the first studies to really show that things matter and why they matter. Many experts in diet and nutrition considered something like this to be the case, but we’ve been awaiting actual evidence for this. They carried out a great preliminary study, and now we need to see if they can get the same results with a larger population.