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Last Updated on July 18, 2023 by Steven Root

What is Butyrate?

Firstly, butyrate is a short chain fatty acid (SCFA) produced when dietary fibers are fermented by our intestinal bacteria (1). Therefore, looking for a list of high butyrate foods or foods with butyrate as many people do, is not really what we should be asking.

Really, we are looking for fibrous foods that allow our bacteria to produce butyrate.

Firstly, Why Should We Care About Butyrate?

Most people’s search for high butyrate foods or foods with butyrate begins because they realize that butyrate reduces intestinal inflammation and restores gut barrier integrity.

More specifically, butyrate-

  • Reduces inflammation of the mucosa & oxidative stress
  • Stimulates proliferation of healthy intestinal cells
  • Inhibits proliferation of cancer cells
  • Modulates intestinal motility (2)
  • 90% of butyrate produced in our gut is metabolized by colonocytes – it is a major source of their fuel (10)

The Proof

The studies linked to below have shown the benefits of butyrate for those diagnosed with ulcerative colitis and Crohn’s disease.

Noteworthily-

  • Butyrate inhibits expressions of pro inflammatory cytokines in Crohn’s disease (3)
  • Increased fecal butyrate concentration improved symptoms in Ulcerative Colitis patients (4)
  • Butyrate combined with mesalamine was significantly more effective in inducing remission in Ulcerative Colitis patients than mesalamine alone (5)
  • Butyrate eliminated bleeding and reduced stool frequency in Ulcerative Colitis patients (6)
  • Butyrate decreased disease activity index & intestinal inflammation in Ulcerative Colitis patients, possibly through inhibition of inflammatory cytokine NF-kappaB (7)
  • Butyrate increases thickness of the mucus layer & improves gut barrier integrity (8)
  • Butyrate supplementation improved quality of life in IBD patients (9)

This is not an exhaustive list. There are many more examples in our scientific literature that attest to butyrate being able to reduce or even eliminate the symptoms of Ulcerative Colitis & Crohn’s disease.

High Butyrate Foods / Foods With Butyrate

As above, a list of foods with butyrate or high butyrate foods does not exist. What do exist, though, are bacteria capable of producing butyrate FOR us when they digest the carbs/fiber we eat. We’ll unpack this in detail below.

Which bacteria produce butyrate?

There is still a lot of research required in this area.

Interestingly, strains of bacteria commonly used in probiotic supplements today are not butyrate producers. This is because butyrate producers seem to be highly anaerobic. They die very quickly in the presence of oxygen, making delivery to the host very challenging.

However, the cross-feeding interaction between microbes present in common probiotic formulas such as bifidobacterium and the butyrate producers mentioned below have been shown to be butyrogenic – that is – butyrate producing.

The Strains Themselves

Of the known butyrate producers found in the digestive tract, most appear to be part of the Lachnospiraceae and Ruminococcaceae families (12).

Faecalibacterium prausnitzii (FP), part of the Ruminococcaceae family deserves special mention since it is one of the most abundant microorganisms present in our digestive tracts and one of the main butyrate producers. Characteristics of FP include anti-microbial activity and anti-inflammatory / immuno-modulatory activity via SCFA (butyrate) production and other complex pathways (14).

Anaerostipes, Roseburia (11), and Coprococcus (15) which are all part of the Lachnospiraceae family are also prominent butyrate producers found in the human gut, as are Eubacterium (16) which are part of the Eubacteriaceae family.

Butyrate producing bacteria are thought to colonize the host within the first year of life, and represent more than 20% of the total bacterial community by adulthood. Various disease states have shown a relative shortage of butyrate producing gut bacteria (14).

So now the question becomes..

Which foods feed butyrate-producing bacteria?

This is the question we should really be asking.. not for a list of foods with butyrate..

And there is a lot of misinformation out there on this question. The generic answer ‘fiber’ is rather vague. However, oddly enough it’s not the worst answer.. Let’s discuss.

Firstly, it’s important to understand the following point-

Strains of bacteria from the same species can respond very differently to very slightly different substrates, even substrates belonging to the same, narrow class of carbohydrate.

That is to say, that almost identical bacteria behave very differently when they encounter almost identical foods.

Example: certain bacteria are able to digest fructans, and some aren’t. And of those that can, some are able to digest fructans with a short chain length, but not fructans with a longer, inulin chain length (16).

The above is just one example of our bacteria’s varying ability to digest different substrates.

And because of this variation, we cannot make a blanket statement like ‘fiber consumption increases butyrate production’.

We need to look at specific types of fiber

One study (17) showed that the production of SCFA’s in kJ was as per the below for different types of carbohydrate:

Fructo-oligosaccharides

In the case of this study, the types of fructo-oligosaccharides (FOS) were foods like onion, asparagus and bananas. The resistant starches (RS) that were used were whole grains & legumes. Whole grains and legumes are actually two food groups that I do not generally recommend that my clients eat. They have the ability to aggravate many gut disorders for reasons that we will not discuss in this post.

Another study (18) showed that supplementation with FOS found in specific kiwifruit resulted in a 100% increase in FP over a 4 week period. This is a major finding as there are numerous studies now reporting that a relative shortage of FP bacteria is linked with several major gut disorders – most notable the inflammatory bowel diseases Ulcerative Colitis & Crohn’s disease.

This study (19) shows that avocados increased the numbers of microbes capable of SCFA production, as well as the total SCFA’s produced.

Reistant Starch

This study (20) shows a significant increase in butyrate production on a diet high in resistant starch type 2 from raw potato and high-amylose maize starch, as well as arabinoxylan found in whole grains. As stated above, I do not generally recommend whole grains to my clients.

This study (21) shows an increase in butyrate production when supplemental resistant starch from potatoes was added to the diets of 174 healthy young adults. Resistant starch from maize, chicory, and corn was also tested. However, the total fecal butyrate increased significantly only when consuming resistant starch from potatoes. In the case of this study it was Bob’s Red Mill unmodified potato starch that was used. Note that there are mixed views on whether this type of resistant starch (RS2) is ‘good’ for humans. Several sources suggest that RS3 is a better source since RS2 appears to feed problematic bacteria. You can find reference to one of those here.

Inulin

This study (22), as well as numerous studies already quoted in this article, shows that inulin can increase butyrate production. This may explain one of the reasons that bananas appear to be so effective in the diets of those suffering from ulcerative colitis & Crohn’s disease. Note, however, that it generally appears that fructans with shorter chain lengths more readily feed butyrate-producing microbes than longer chain fructans such as inulin.

This study (23), interestingly, showed that supplementary inulin, whilst capable of altering the host’s microbiota, did not increase butyrate levels. Albeit this result seems to be against the grain with numerous studies attesting to the efficacy of supplementary inulin in increasing SCFA production in our guts.

The deeper this rabbit hole goes, the more we see just how variable our abilities to produce butyrate are.

Our ability to produce butyrate by fermenting dietary fibers appears to depend on-

  • The richness of specific butyrate-producing microbes present in our guts
  • The cross-feeding interactions between microbes present in our guts
  • The specific substrate available to these microbes

Whilst this variability can make it tricky to recommend a diet capable of increasing butyrate production, the common, recurring observation seems to be

Resistant starch and fructans (both short chain FOS and long chain inulins) produce butyrate when fermented in our guts.

In the case of resistant starch, it would appear most studies have focused on RS2. However RS3 has, on a number of occasions, been reported to produce higher levels of butyrate and be more healthful to humans.

The Butyrate Foods List

(please read the Words of Caution at the end of this article before rushing to change your diet)

The following foods are likely to increase butyrate production in our guts..

Resistant Starches

Cooked and cooled: potatoes, sweet potatoes, rice, pasta, oats, beans, legumes, whole grains.

Raw: Green bananas, potatoes, potato starch, green banana flour.

Fructans

Onions, chicory, bananas, artichokes, asparagus, garlic, leeks, broccoli, pistachios, & various extracts.

In Summary

We are not looking for a list of high butyrate foods or foods with butyrate.

We are looking for foods that FEED our butyrate producing bacteria.

And due to the significant variability in resident microbes person-to-person, their varying ability to digest certain substrates, and the highly complex cross-feeding interactions between resident microbes in our guts..

Consuming a diet that includes a number of resistant starches and fructans would seem sensible to increase butyrate production.

Words Of Caution

If you are struggling with a gut disorder, ironically, some of these foods can be triggering since they do not allow for much bowel rest. Therefore, they may not be the best idea if you still have symptoms of an existing gut disorder. It may be wise to introduce them once symptoms have resolved.

If you would like help in resolving symptoms and building out a foods list that you can reliably eat day in day out to stay symptom free, you can get that here.

Share this article folks, let’s get the word out.