Every human being on Earth is responsible for the health of this beautiful planet. Our actions, whether good or bad, have consequences. So collectively, we can have a big impact, and that’s quite a responsibility. For example, getting so many individuals to work in harmony is no small feat.
Yet, within our very own ecosystems, specifically the human gut, harmony is exactly what we need to achieve optimum health. The human gut is populated by trillions of bacteria, both good and bad. These colonies have jobs to do. Get the balance right, and you’re on to a winner, good health, but get the numbers wrong, and you could be heading towards poor health.
Nestled amongst these trillions of microbes is Faecalibacterium prausnitzii, a beneficial butyrate producer which has anti-inflammatory properties that help to support good gut health.
It is one of the most abundant species in the human gut and is considered one of the main butyrate producers, an important short-chain fatty acid. Interest in this bacterium is growing because of its crucial role in human health and gut physiology. Hence, why it has been identified as a ‘good’ gut microbe by the PREDICT 1 study.
In this article, we take a good look at this microscopic friend, what its health benefits are, and how you can help to boost its abundance in your gut.
Content outline
- What is Faecalibacterium prausnitzii?
- Faecalibacterium prausnitzii benefits
- How to increase Faecalibacterium prausnitzii
- Summary
What is Faecalibacterium prausnitzii?
Faecalibacterium prausnitzii belongs to a group of bacteria called Firmicutes and is one of the most common species found in the colon. It is rod-shaped (but you can only see it under a microscope), gram-positive (has thick mesh-like walls), and anaerobic (does not require oxygen for growth).
F. prausnitzii is a butyrate-producing bacteria. The short-chain fatty acid (SCFA), butyrate, is the main source of energy used by the cells that line the gut. It has also been shown to have anti-inflammatory properties [1]. F. prausnitzii transforms undigested dietary fibre into butyrate, where it can then be utilised for many vital functions.
Researchers from the PREDICT studies have found F. prausnitzii in the gut of nearly all study participants (99.7%) [2]. Other members of the Firmicutes phylum include Lactobacillus, Bacillus, and Clostridium.
Where is Faecalibacterium prausnitzii found in the body?
Faecalibacterium prausnitzii is found in the colon. In healthy individuals, it is normally found in high abundance. There are different suggestions surrounding its exact quantity, but the consensus is that it makes up between 5% and 15% of the total gut microbiota [3].
The numbers of Faecalibacterium prausnitzii are reduced in people suffering from inflammatory gut diseases and people who are obese. Here percentages are seen to range between 1% and 6% [4].
F. prausnitzii is a unique bacterium in that it is the only known species in the Faecalibacterium genus.
Faecalibacterium prausnitzii benefits
The reason Faecalibacterium prausnitzii is considered a good microbe is because it is one of the main butyrate producers in the gut. Butyrate is an example of a short-chain fatty acid and is important for keeping your gut healthy.
Butyrate is produced by gut microbes when they ferment or break down dietary fibre. It has numerous health and gut microbiome benefits, including:
- provides energy for the cells lining the gut
- anti-cancer and anti-inflammatory properties
- maintaining gut homeostasis [5].
The PREDICT 1 study listed F. prausnitzii as a good microbe because of its butyrate-producing properties and the beneficial impact this can have on gut health. In fact, this molecule is so powerful, it can reduce the risk of developing inflammatory bowel disease and colorectal cancer.
Lowers insulin secretion and increases healthy fats
That’s not all, the PREDICT 1 study also found an interesting link between this bacterium and insulin and fat levels. The study found that an individual’s gut microbiome composition is a good indicator of their cardio-metabolic markers [6].
The PREDICT studies found that a greater abundance of F. prausnitzii was associated with lower insulin secretion and a high level of healthy or polyunsaturated fat. But what does that mean for health?
Well, insulin is a hormone released by the pancreas in response to rising blood sugar levels. It helps to move sugar into the body’s cells where it can be used for energy. The secretion of insulin works on a feedback loop, so if there is a low level of insulin in the blood, the liver is alerted to release some stored blood sugar for energy use. Alternatively, if blood sugar levels rise, perhaps in response to food, a signal is sent to the pancreas to release insulin.
It's clever stuff but too much insulin in the blood can also be harmful for the body and can increase the risk of developing metabolic diseases such as type 2 diabetes, heart disease, and obesity [7].
The study also found that a higher abundance of Faecalibacterium was linked to higher levels of healthy fats in the blood. Previous research has also shown that fats from plant-based sources, such as nuts and oils, are associated with positive changes in the diversity of the gut microbiome and can increase the abundance of important butyrate producers, such as F prausnitzii [8].
What does this all mean?
Overall, the findings of the PREDICT 1 study and other emerging research linked to Faecalibacterium prausnitzii, show that it may be possible to target the gut microbiome through personalized nutrition to reduce the risk of developing metabolic disease.
How to increase Faecalibacterium prausnitzii
The PREDICT study found that there are links between the abundance of the 15 good and 15 bad gut microbes and specific foods. In other words, the food you eat can determine the overall composition of your gut microbiome.
In short, the best way to ensure a diverse ecosystem in your gut is to eat plenty of fiber, and by that, we mean lots of plant-based foods. Some research shows that inulin-type fructans can increase the abundance of F prausnitzii [9]. These are examples of prebiotic fibers, the type that help to nourish your gut bacteria [10] and are found naturally in many fruits, vegetables and wholegrains. Foods that increase F. prausnitzii include:
- bananas
- garlic
- leeks
- onion
- wheat [11].
If you want to improve the diversity of your gut microbiome, you’ll need to make sure you are incorporating plenty of high fiber foods into your diet. Specifically, foods such as:
- beans
- fermented foods
- fruit
- legumes
- nuts
- seeds
- vegetables
- whole grains
HMO Prebiotics and F. prausnitzii
Human milk oligosaccharides or HMOs are found in large quantities in human breast milk and are renowned for their positive health benefits for infants. More recent research, however, has shown that HMOs are also important for adult health.
In the gut, HMOs act like prebiotics, in other words, they help to nourish beneficial gut bacteria and support the immune system. In the case of Faecalibacterium prausnitzii, a study conducted in 2021 found that the HMO, 2’-Fucosyllactose, increased the stool count of F prausnitzii in adults [12].
The following figure from a previous publication also shows the presence of Bifidobacteria longum in your gut helps the growth of both B. longum spp. infantis and F. prausinitzii when fed with different HMOs.
Want to know more about HMOs? Click here.
Summary
Faecalibacterium prausnitzii is part of a group of bacteria called Firmicutes and is a common inhabitant of the human gut. Researchers from ZOE have identified F prausnitzii as one of the 15 good gut microbes outlined in their study.
The main reason for this is because this bacterium is believed to be one of the main bacterial producers of butyrate, an important microbial metabolite produced because of the bacterial fermentation of fiber. Butyrate has many important functions for human health. There is also an association between the abundance of F prausnitzii and insulin secretion and polyunsaturated fat levels.
Because Faecalibacterium prausnitzii is so important for supporting your gut and general health, it is important to eat a healthy and diverse diet as well as make healthy lifestyle choices, such as choosing prebiotics for gut microbiome health, to keep the abundance of gut bacteria linked to inflammation in check.
Author details
Written by: Beau Berman
Reviewed by: Leanne Edermaniger, M.Sc. Leanne is a professional science writer who specializes in human health and enjoys writing about all things related to the gut microbiome. She has written extensively on inflammatory bowel disease, prebiotics, and microbiome research.
Her work focuses on translating complex medical science into evidence-based, practical health guidance.
Last updated: March 2026
