Oat flakes have played an important role as a food since the beginning of history. While oats were long considered a simple food in times of crisis and "poor man's food", they have received more and more attention in recent years - and rightly so. Scottish cuisine has helped oats gain global fame with its national dish, "brochan" (English "porridge"). But why are oats a special food that we should include in our diet? How and why can we benefit from consuming oats?
A study recently published in the Nutrients Journal addressed exactly this question. A team of researchers from the USA and Brazil investigated the connection between the consumption of oats and the human gut microbiome. The scientists discussed the health benefits of the metabolites produced by the gut microbiome, primarily short-chain fatty acids.
In this article we would like to focus on the findings of this study.
Oats – A traditional & underrated superfood
Oats have a long history as a food, dating back to ancient Rome and Greece. During the Middle Ages, oats were a staple food for the lower classes in many regions of Europe, particularly as animal feed and as a meal in the form of porridge or bread.
Oatmeal has established itself as a staple food over the centuries because it is a source of proteins such as prolamins and globulins, as well as fiber that keeps you full for a long time.
Today we know that the nutritional properties of oats go far beyond the satiating effect. Oats are a healthy, fiber-rich food that can have a positive effect on our intestinal flora because fiber is fermented in the intestines to form short-chain fatty acids.
Short-chain fatty acids (SCFAs) are metabolic products that are produced in the intestine through the fermentation of indigestible fiber and other carbohydrates by certain intestinal bacteria. SCFAs help maintain the integrity of our intestinal barrier by increasing the density of tight junctions (= tight junctions are protein structures between the cells of the intestinal mucosa that control the permeability of the mucosa). An intact intestinal barrier is important to prevent unwanted substances from entering the body.
Short-chain fatty acids also have anti-inflammatory properties. They can reduce the release of inflammatory cytokines and thus help reduce inflammation in the intestine. This is particularly relevant in chronic inflammatory bowel diseases such as Crohn's disease or ulcerative colitis.
Short-chain fatty acids (SCFAs) can also modulate the immune system. They can support regulatory T cells, which play a role in maintaining immune homeostasis and preventing excessive inflammatory responses.
All of these bioactive properties make oats a valuable food for the intestinal flora, as they are a valuable source of both soluble and insoluble fiber. Oats also contain plant proteins and antioxidant compounds.
Due to its phenolic compound, lipid and fiber content, it is considered a healthy and efficient food that is a good source of prebiotics . Oats can even be consumed by people with celiac disease due to its lack of gluten.
With their prebiotic potential, the fiber-rich oat flakes are considered a functional food that can have a positive effect on our intestinal microbiome and our general well-being. Functional foods are foods that have properties that go beyond pure energy supply. Functional foods are said to offer health benefits.
To understand more precisely why oats should be considered a functional food, we need to look at its effects on our gut microbiome. But what exactly is the gut microbiome?
What exactly is the gut microbiome?
Our gut microbiome consists of a number of microorganisms that colonize the intestines and ferment not only nutrients but also fiber from our food. A healthy gut microbiome, which is mainly populated by beneficial microorganisms, has a positive effect on digestion and plays an important role in disease prevention.
Dysregulation of our gut microbiota can lead to various diseases. Our diet therefore plays an important role in determining the composition of the gut microbiota.
The effects of oat consumption on the gut microbiota have not yet been fully investigated. Relationships between oat consumption and the abundance of probiotic gut bacteria such as Akkermansia muciniphila, Roseburia, Lactobacillus, Bifidobacterium and Faecalibacterium prausnitzii have already been observed and proven.
Therefore, the study discussed in this article summarizes an integrative review of previous findings from studies on the relationship between oat consumption, the gut microbiota and the metabolites it produces, mainly short-chain fatty acids.
The effects of oat consumption on our gut microbiome
Our diet has a significant impact on our health, which is determined not least by the diversity and functionality of our gut microbiome. The gut microbiome plays an important role in metabolism, nutrient digestion and absorption, as well as immunomodulatory and endocrine functions. In addition, the gut microbiome is also involved in maintaining the integrity of the mucus layer and improving intestinal permeability.
Foods containing fiber with prebiotic properties contribute to the modulation of the intestinal microbiota and have therefore recently been of great research interest.
The main bioactive compounds in oats include β-glucan, flavonoids, vitamin E, phenols, avenanthramides and phytosterols.
Vitamin E is known to have anti-inflammatory and antioxidant properties that are believed to reduce the risk of cardiovascular disease and cancer. Phenolic compounds such as caffeic, phytic, coumaric and vanillic acids, as well as over 25 avenanthramides found in oats, are also thought to have powerful antioxidant properties.
Many studies have also investigated the antiatherogenic (prevention of arteriosclerosis), proapoptotic (programmed cell death), antiproliferative (inhibition of uncontrolled cell growth) and anti-inflammatory properties of avenanthramides.
The contents of the study – The relationship between oat consumption and the gut microbiome
In the present study, researchers conducted an integrative review of original articles including in vivo, in vitro and clinical studies published between 2012 and 2023 investigating the use of oat products and oat-containing supplements in modulating gut microbiome function.
The soluble fiber β-glucan has been extensively studied as a prebiotic and has cholesterol-lowering and hypoglycemic effects. Furthermore, fermentation of β-glucan by the gut microbiota is believed to produce acetate, butyrate, propionate, short-chain fatty acids and thus affect the composition of the gut microbiome.
Unique phenolic compounds such as avenanthramides, avenacolysates and avenacins found in oats are believed to have anti-inflammatory and antioxidant properties and may protect against colon cancer, coronary heart disease and dermatological problems.
Dysbiosis (pathological disturbance of the bacterial colonization of the intestine) of the gut microbiome has been linked to various diseases such as psoriasis, tuberculosis, Parkinson's disease and even psychological and cognitive problems.
The results of the study – Oats are beneficial for the intestines and a functional food
The results of the study show that oats are an excellent source of fiber and can help meet the adequate fiber needs of adults.
Furthermore, oats should be considered a functional food due to their protein, carbohydrate, unsaturated fatty acid, mineral, vitamin and insoluble fiber composition, as well as the presence of β-glucan, which has cholesterol-lowering properties.
While the U.S. Food and Drug Administration (FDA) does not have a regulatory definition for the term “functional food,” it has approved the use of soluble fiber from oats to reduce the risk of coronary heart disease.
Other studies also show that consuming oats is effective in lowering low-density lipoprotein and total cholesterol levels in overweight or obese individuals and in patients with type 2 diabetes.
A meta-analysis in the review found that β-glucan consumption was associated with a significant reduction in total cholesterol. The researchers discussed several mechanisms by which β-glucan may lower cholesterol levels.
β-glucan is thought to increase the viscosity of intestinal contents, thereby limiting the reabsorption of bile acids in the terminal ileum, the last section of the small intestine, resulting in the excretion of bile in the feces. The reduction in bile acids triggers the de novo synthesis of bile acids, which utilizes cholesterol.
Furthermore, β-glucan is thought to modulate the composition and function of the gut microbiome, with the increase of bacteria such as Lactobacillus, Bacteroides and Bifidobacterium with high bile salt hydrolase activity playing an important role in deconjugating bile acids and limiting their reabsorption.
New data also suggest that fermentation of fiber by the gut microbiome produces short-chain fatty acids that inhibit the release of renin by activating receptors in the blood vessels and kidneys, thereby lowering blood pressure.
While further studies on the health benefits of short-chain fatty acids are needed, initial evidence suggests that β-glucan from oats promotes the growth of beneficial gut microbiota and exhibits prebiotic properties through fermentation and production of short-chain fatty acids.
Overall, the review in the study provided a comprehensive overview of current research on the positive effects of oat consumption on gut microbiome function and short-chain fatty acid synthesis.
Evidence from various studies suggests that the soluble and insoluble fiber and phenolic compounds in oats provide a wide range of health benefits, including cholesterol-lowering, anti-inflammatory and antioxidant properties.
oat products from THE CHANGE
Microbiome Porridge
Our gut microbiome porridge was designed based on the health benefits of oats, among other things. The microbiome porridge is an easily digestible oat meal with Swiss organic oat flakes and Swiss milk protein. The porridge contains no sugar or artificial additives. The oat flakes are rich in beta-glucans, which help maintain normal blood cholesterol levels and regulate the function of the gut microbiome.
A positive effect can be seen with a daily intake of just 3g of oat beta-glucans. The low glycemic response of the formula is gentle on the pancreas.
The fructo-oligosaccharides (FOS) and a little banana powder contained in the porridge provide a natural and mild sweetness. Our porridge not only provides a healthy and filling meal, but also nourishes the good intestinal bacteria. Our microbiome porridge can help build up the intestinal flora and keep it fit.
Protein Porridge ORGANIC
The Swiss Smart Food® Protein Porridge is a delicious and nutritious oat meal and perfect for a healthy and filling start to the day. The oat flakes are rich in fiber and high-quality protein and are made from selected organic ingredients. The porridge is available in three different varieties: Berries, Swiss Chocolate Cacao Nibs and Dates, Figs & Cinnamon.
Our Protein Porridge BIO has a low glycemic response to regulate blood sugar and protect the pancreas. The oat flakes also contain numerous vitamins, such as vitamin B1, vitamin B2, vitamin B6, vitamin K and vitamin E. The oat flakes are also rich in trace elements and minerals: iron, calcium, potassium, phosphorus, zinc, copper, magnesium, selenium and manganese are all contained in oat flakes.
Sources :
- Fabiano, GA; Shinn, L.M.; Antunes, AEC Relationship between Oat Consumption, Gut Microbiota Modulation, and Short-Chain Fatty Acid Synthesis: An Integrative Review. Nutrients 2023, 15, 3534.
- EFSA Panel on Dietic Products, Nutrition and Allergies (NDA). Scientific Opinion on the Substantiation of a Health Claim Related to Oat Beta Glucan and Lowering Blood Cholesterol and Reduced Risk of (Coronary) Heart Disease Pursuant to Article 14 of Regulation (EC) No 1924/2006. EFSA J. 2010, 8, 1885.
- Chavez de la Vega, MI; Alatorre-Santamaría, S.; Gómez-Ruiz, L.; García-Garibay, M.; Guzmán-Rodríguez, F.; González-Olivares, LG; Cruz-Guerrero, A.E.; Rodríguez-Serrano, GM Influence of Oat β-Glucan on the Survival and Proteolytic Activity of Lactobacillus Rhamnosus GG in Milk Fermentation: Optimization by Response Surface. Fermentation 2021, 7, 210.
- Butt, MS; Tahir-Nadeem, M.; Khan, MKI; Shabir, R.; Butt, MS Oat: Unique among the cereals. Eur. J. Nutr. 2008, 47, 68-79.
- Carlson, J.; Erickson, J.; Hess, J.; Gould, T.; Slavin, J. Prebiotic Dietary Fiber and Gut Health: Comparing the in Vitro Fermentations of Beta-Glucan, Inulin and Xylooligosaccharide. Nutrients 2017, 9, 1361.
- Fehlbaum, S.; Prudence, K.; Kieboom, J.; Heerikhuisen, M.; van den Broek, T.; Schuren, F.; Steinert, R.; Raederstorff, D. In Vitro Fermentation of Selected Prebiotics and Their Effects on the Composition and Activity of the Adult Gut Microbiota. Int. J. Mol. Sci. 2018, 19, 3097.
- Rose, DJ Impact of Whole Grains on the Gut Microbiota: The next Frontier for Oats? Br. J. Nutr. 2014, 112, S44–S49.