The Good Gut

The Good Gut by Justin and Erica Sonnenburg is an interesting first look at the state of research into our gut. They are good at pointing out that we don’t know much yet and that much more research needs to be done. There are some recommendations (eat more fibres) sprinkled throughout the book. And they use their personal life to reflect on the choices they have made regarding nutrition.

One thing that is very interesting about the gut, is that we can have much more influence over it than our genes (at least at this moment in time). If we eat right, manage our stress, and exercise, our gut might make us very happy.

The interaction between our gut, brain, and rest of the body is not very clear. What is suggested, is that the interactions go both ways. Stress will negatively impact your gut. And your gut microbiota will influence how you feel.

One of the more striking examples they use is autism. They argue that your gut microbiota might have an influence on how you interact with the rest of the world. The research is still in the early stages, and although it isn’t clear-cut, they do make a good case to keep on researching this.

The gut and inflammation are also linked. One of the things I’ve learned about longevity is that inflammation increase with age (the background level of inflammation, inflammaging) and that, of course, this is bad. You want your body to react to pathogens, but not be constantly active.

Here are some quotes/ideas:

  • “Thanks to our typical diet, the average American’s gut bacteria are starving.” They mention that we have about 1/3rd less diversity (which you want) than people living in more indigenous cultures.
  • Our gut contains 100 trillion bacteria. Some live in your stomach, some in your small intestine, most in your large intestine.
  • They use the analogy of a tube, for our body, that starts at the mouth and ends at the anus.
  • “Close to half of the mass of stool are bacteria”
  • Because of (mass) agriculture, we eat mono-crops and mess up our digestive system.
  • Antibiotics kill bacteria in your gut. Kids in the US undertake (on average) more than 1 antibiotics session per year. Although antibiotics are awesome (they save millions of lives), the overuse of them is terrible for your gut.
  • Having a non-c-section birth helps you with starter bacteria. Again in the US, too many babies are born through a c-section. If remembered correctly, the Netherlands is one of the best countries (least c-sections).
  • Our gut microbiota is in contact with the immune system and communication goes both ways.
  • One hypothesis is that because we’re too hygenic, our immune system isn’t doing much, so has ‘time’ to react to pollens and other allergens.
    • “The microbiota is like a mercenary in the eyes of the immune system, paid (in slimy mucus) for helping to exclude bad germs but not trustworthy enough to go completely unmonitored.”
    • “The microbiota … also tunes the magnitude and duration of the immune system response”
  • Owning a pet can help you have a more diverse microbiota
  • Probiotics might help your microbiota, yet we don’t know enough about it to be sure which ones help best. Supplements should therefore be looked at with caution and eating yoghurt, kimchi, tempeh and other fermented foods are probably best.
  • Prebiotics (the food-derived components, polysaccharides/dietary fibre) is what your microbiota likes to eat. Inulin is a good example. The skin of fruits also has them. Your gut loves them.
  • One of the food recommendations is sourdough bread. I might take them up on the offer. What they put it against is white flour and other ‘rich man’ foods that contain no fibre.
  • Another food thing to watch for is to see if your yoghurt contains live bacteria or that they are missing them.
  • With regards to aging, eating a diet rich in MACs (fibres/food for your microbiota) and low in saturated fats from animal sources, you might add some years.