Our gut bacteria helps the body digest food, make key nutrients, fight harmful organisms, protect our gut lining, train our immune systems, turn genes on and off, regulate gut hormones, and can even affect our moods. Changes to our gut bacteria are often linked to a compromised immune system, weight gain, inflammation, cancer, diabetes, and heart disease.
The saying 'you are what you eat' is very true when it comes to our gut. When we eat something, the bacteria mirror it and quickly respond when our diet changes.
Just five days into a diet high in animal fat and low in fiber causes a rise in bile-tolerant bacteria, which are linked to inflammatory bowel disease1. This type of bacteria produces more secondary bile acids (carcinogenic compounds formed when bacteria metabolize bile) and fewer beneficial fiber-fermenting bacteria.
By contrast, if you eat foods that are high in complex carbohydrates and fiber it will diversify your gut bacteria, lower markers leading to colon inflammation, and lead to a 70% drop in secondary bile acids2.
Butyrate is a type of short-chain fatty acid that produces gut bacteria. It also reduces inflammation in all parts of the body and keeps the tissues of the gut healthy. Butyrate slows down the growth of harmful bacteria, kill cancer cells, stimulates appetite-suppressing hormones, and promotes fat burning in muscle cells which can lower insulin resistance3.
How is it possible to get the most out of this incredible nutrient? It all comes down to fiber, which is fermented into butyrate by the healthy bacteria in the gut. All types of fiber are necessary for a healthy diet, particularly those from a variety of plant foods, whole grains, and starches found in legumes.
Different types of foods are more likely to promote the growth of friendly gut bacteria. These include prebiotic foods such as asparagus, sweet potatoes, oats, beans, onions, and garlic. You can also provide live and beneficial bacteria to the gut by eating probiotic foods such as sauerkraut, kimchi, nondairy yogurt, and other fermented foods.
In addition to eating prebiotic and probiotic foods, it is recommended that you take a probiotic supplement daily to boost the levels of healthy gut bacteria.
https://www.ncbi.nlm.nih.gov/pubmed/?term=PMID%3A+24336217, Diet rapidly and reproducibly alters the human gut microbiome, 2014 Jan 23;505(7484):559-63. doi: 10.1038/nature12820. Epub 2013 Dec 11
https://www.ncbi.nlm.nih.gov/pubmed/25919227, Fat, fibre and cancer risk in African Americans and rural Africans, 2015 Apr 28;6:6342. doi: 10.1038/ncomms7342
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3070119/, Potential beneficial effects of butyrate in intestinal and extraintestinal diseases, 2011 Mar 28; 17(12): 1519–1528