Wednesday, December 12, 2012

Human Food Project article on fat and gut bugs

This article is awesome for 2 reasons.  For one, I have been discussing with clients how the Paleo diet doesn't tend to work if you don't eat loads of vegetables.  Secondly, I am halfway done a blog post on a presentation at the Ancestral Health Symposium on why we have evolved to eat fat.  So what is the interesting tidbit about this article?

The author of this article discusses an interesting link between eating fat and a species of gut bacteria called bifidobacterium.  In mice fed a high fat diet in the absence of bifidobacterium in the gut, obesity ensued.  In mice with bifidobacterium fed the same diet, they remain lean.  So what is this link and how does it work?

A high fat diet leads to low grade inflammation that correlates with an increase in an endotoxin called lipopolysaccharide (LPS).  The LPS leaks from the gut in to the serum and can lead to a whole host of problems including obesity and diabetes.  But how does the LPS get from the gut to the serum?  One study tested this out.

Researchers fed one group of mice a high fat diet and another group a high fat diet and a prebiotic that feeds bifidobacterium.  They found an increase in serum LPS in the group fed only the high fat diet while the group fed the prebiotic with the high fat diet had normal LPS levels.  The theory is that the prebiotic feeds the bifidobacterium which then increase in number and produce fatty acids that heal the gut lining, preventing LPS from entering the serum and causing problems.

So what foods do these prebiotics come from?  The soluble fiber found in plants such as onions, garlic, leeks, and dandelion greens just to name a few.  This explains why a paleo diet that focuses only on meat fails in some people, especially people who are obese and have low levels of bifidobacterium in the first place.  Fix the gut imbalance and fix the problem.