October 1, 2020
The microbes living in your gut - known as the microbiome - are crucially important to your health.
Results from our PREDICT study show that there is a distinct signature of ‘good’ and ‘bad’ microbial species in your gut that are strongly associated with 'good' and 'bad' markers of health. We have also identified specific foods and dietary patterns that encourage these ‘good’ and ‘bad’ bugs to thrive.
The gut microbiome is hugely variable from person to person. Through our research, we have found that even identical twins have very different gut microbiomes, with unrelated individuals sharing 30% and twins sharing 34% of the same gut microbes.
If we zoom in even closer it becomes clear that each of us has a unique set of genetic variants (strains) of each microbial species present in each of our guts. This makes us unique microbially!
But just because your microbiome is unique to you doesn't mean it's permanent. While you can’t change your genes, you can modify your microbiome.
You may have heard the terms prebiotics, probiotics, and postbiotics, referring to foods and supplements that claim to boost the ‘good’ bacteria in your gut.
Prebiotics are nutrients in food that we can't digest ourselves, such as fiber. Instead, they provide food for the bacteria in your gut and encourage their growth.
The microbiome functions like any ecosystem – survival of the fittest - so the bugs that survive in your gut are the ones that have plenty to eat.
And if you provide the right food, the microbes that like to eat it will come, just like putting out birdseed will encourage feathered friends to visit. So eating prebiotics can help increase the number and diversity of organisms in our microbiome.
Unsurprisingly, lots of the molecules we need to feed our gut bacteria come from our food.
To count as a 'prebiotic,' the molecule must selectively stimulate the growth or activity of microbes that are beneficial to our health. Most prebiotic molecules are plant fibers, so eating lots of plants is always a good start!
Here are some of the most common prebiotic molecules and where you can find them:
The World Health Organization defines "probiotics" as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host." In other words, they are living microbes in food that make it to your gut and (hopefully) set up camp there, providing some kind of benefit.
Eating probiotics may help increase the number and diversity of the bacteria in our gut, this can help reduce the growth of pathogenic microbes living in our gut, aid digestion, boost the helpful chemicals that our gut bacteria produce (more on that below), and prime our immune system.
Fermented foods, including yogurt, kefir, kimchi, and sauerkraut contain live bacteria and act as probiotics.
As microbes in your gut eat prebiotics in your food, they produce waste molecules called metabolites. These waste molecules, along with dead cells and parts of cells produced by your microbiome, are known as 'postbiotics.'
In this case, our gut bugs’ trash is our body’s treasure.
Scientists have identified hundreds of postbiotic chemicals that are produced in the microbiome and play many different roles in protecting your health. They include:
A healthy, diverse microbiome that is well fed will naturally produce metabolites, so if you keep your microbiome robust and healthy, it will keep churning out those yummy postbiotics. Some foods also contain postbiotic chemicals like short-chain fatty acids, and you can buy supplements containing postbiotics, which may offer some benefits to some people.
If you want to learn more about the microbes in your gut, take a look at the ZOE test kit, which includes the most advanced gut microbiome test in the world. We use deep shotgun sequencing to understand exactly which bacteria call your gut home to provide you with personalized recommendations for foods that support optimal gut health.
Want to understand how ZOE can help you discover the best foods for your gut bugs? Click here for our free evaluation.