Oatmeal has had an important role as a food since the beginning of history. While oats have long been considered a simple food in times of crisis and a "poor man's food", they have received more and more attention in recent years - and rightly so. Scottish cuisine has its national dish, “brochan”, oats. “Porridge”, helped to achieve global fame. But why are oats a special food that we should include in our diet? How and why can we benefit from consuming oats?
A recently published study in the Nutrients Journal addressed exactly this question. A team of researchers from the USA and Brazil examined the connection between oat consumption and the human gut microbiome. The scientists discussed the health benefits of the metabolites produced by the intestinal 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. In the Middle Ages, oats were a staple food for the lower classes in many regions of Europe, particularly as livestock 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. The 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 mucous membrane). 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 gut. This is particularly relevant for 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, with their valuable source of both soluble and insoluble fiber, a valuable food for the intestinal flora. 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 their lack of gluten.
With their prebiotic potential, the fiber-rich oat flakes are considered a functional food that can positively influence our intestinal microbiome and our general well-being. Functional foods are when the properties of a food go beyond pure energy supply. Functional foods are said to provide health benefits.
To further understand why oats should be considered a functional food, we need to look at their effects on our gut microbiome. But what can you actually imagine by the intestinal microbiome?
What exactly is the gut microbiome?
Our intestinal microbiome consists of a number of microorganisms that colonize the intestine and ferment not only nutrients but also fibers from our food. A healthy intestinal microbiome, populated primarily 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 intestinal microbiota.
The effects of oat consumption on the intestinal microbiota have not yet been fully researched. Associations between oat consumption and the abundance of probiotic intestinal 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 the 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 influence on our health, which is determined not least by the diversity and functionality of our intestinal 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 are therefore of great research interest recently.
The most important 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 reported to have powerful antioxidant properties.
Many studies have also examined 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 intestinal 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, examining 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 exhibits cholesterol-lowering and hypoglycemic effects. Furthermore, it is assumed that the fermentation of β-glucan by the intestinal microbiota produces acetate, butyrate, propionate, short-chain fatty acids and thus affects the composition of the intestinal microbiome.
Unique phenolic compounds such as avenantramides, avenacolysates and avenacins found in oats are believed to have anti-inflammatory and antioxidant properties. They could protect against colon cancer, coronary heart disease and dermatological problems.
Dysbiosis (pathological disorder of intestinal bacterial colonization) 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 adults' adequate fiber needs.
Furthermore, oats should be considered a functional food due to the 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 eating oats is effective in reducing low-density lipoprotein and total cholesterol levels in overweight or obese people and in patients with type 2 diabetes.
A meta-analysis in the review found that consumption of β-glucan was associated with a significant reduction in total cholesterol. The researchers discussed various mechanisms by which β-glucan can 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 portion of the small intestine, resulting in the excretion of bile in feces. Lowering bile acids triggers de novo synthesis of bile acids that utilizes cholesterol.
Furthermore, β-glucan is believed to modulate the composition and function of the gut microbiome, with the increase in 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 suggests 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 are needed on the health benefits of short-chain fatty acids, initial evidence suggests that oat β-glucan 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.
The evidence from the various studies suggests that the soluble and insoluble fiber as well as the phenolic compounds in oats provide a wide range of health benefits, including cholesterol-lowering, anti-inflammatory and antioxidant properties.
Oat products from THE CHANGE
Our intestinal microbiome porridge was designed based on the health benefits of oats, among other things. The Microbiome porridge is an easily digestible oat meal with organic Swiss oat flakes and Swiss milk protein. The porridge contains no sugar or artificial additives at all. The oat flakes it contains are rich in beta-glucans, which help maintain normal blood cholesterol levels and regulate the function of the intestinal microbiome.
A positive effect can be seen from a daily intake of 3g of oat beta glucans. The formula's deep glycemic response is gentle on the pancreas.
The fructo-oligosaccharides (FOS) contained in the porridge and a little banana powder ensure 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 deep glycemic response to regulate blood sugar and protect the pancreas. The oat flakes also contain numerous vitamins, such as: E.g. vitamin B1, vitamin B2, vitamin B6 as well as vitamin K and vitamin E. Oat flakes are also not lacking in trace elements and minerals: iron, calcium, potassium, phosphorus, zinc, copper, magnesium, selenium and manganese are contained in oat flakes.
- 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.