The first question naturally will be, "how do I change my gut bacterial composition?"
*Will this give birth to a new wave of suppository nutritional products and colon fecal transplants?
One thing I noticed is that the authors have a patent for weight loss prediction biomarkers. Not sure how that might have biased their results, or if they may have focused mainly on what they wanted to prove versus all possible explanations.
It seems like the study found no difference between the two diets for people with the low P/B community (no matter what you eat, you can't lose weight if you have low P/B), while people with high P/B community lost weight on the "new" high protein, hgh fiber, low fat diet with lots of fruits and vegetables. It seemed that, on both diets, partipants were allowed to eat ad libitum, which makes me wonder if the total calories consumed could explain the success of the high protein, high fiber diet. Many dieters claim high protein, high fiber is more satiating than high carb diets, so perhaps partipants ate less calories on the more satiating diet. This wouldn't explain why P/B ratio correlates with weight loss, though, so there's still something to further investigate there.
The authors note that only two partipants switched P/B ratio throughout the study, suggesting that diets high in fiber don't affect P/B ratio. Maybe this means, before dieting, some other intervention is required (dietary or drug?) for successful weight loss. I do still wonder how total calories or other dietary components affect the results, or if total calories or other dietary components influence gut microbe communities in ways protein and fiber don't.
Were the two different diets matched in terms of total calories consumed?
Don't Western diets have high sugar contents, and are the more important macro to be aware of?
Did each of they groups eat an equivalent amount of calories? If not, I would say the results of the study should not be viewed as conclusive.
"The research team found that relationship between two groups of intestinal bacteria was decisive for whether overweight people lose weight on a diet that follows the Danish national dietary recommendations and contains a lot of fruit, vegetables, fiber, and whole grains."
My next question would be: are these gut bacteria important because participants were placed on a high plant matter diet? Or can these results be replicated on a keto diet/western diet with calorie restriction?
So the question is: Are the people eating the New Nordic diet creating gut bacteria composition that allows them to lose more weight, and the danish national diet does not actively feed that specific biome? Or do the people naturally have that gut biome and it is maintained by some other source?