Microbiome Diet ~ 3. Boost the Beneficial Microbes
What you eat plays a big role in your gut health. Some foods are beneficial for your gut bacteria, while others have the opposite effect. So which foods are boosts the beneficial microbes that live in your gut?
This is part 3 of the articles about the Microbiome Diet. Read part 2 here: Microbiome Diet 2: Animal foods and part 4.1 here: Microbiome Diet 4.1: Harmful foods - Alcohol .
Plants are preferred
Current dietary guidelines targeting the gut microbiome [ 1 , 2 , 3 , 4 , 5 ] seem to disagree on the specifics. However, there is general agreement that eating more plant-based foods is good for you, the planet, and your gut health.
Plant-based foods contain many nutrients, such as vitamins , minerals and dietary fiber . In addition, they are rich in a universe of active chemicals that not only feed the good bacteria, but also provide countless benefits for your overall health: polyphenols.
Researchers suggest that long-term consumption of a diet rich in plant polyphenols provides protection against the development of cancer, cardiovascular disease, diabetes, osteoporosis, and neurodegenerative diseases. Those who eat a plant-based diet tend to have a much lower risk of developing serious health conditions .
But what exactly are polyphenols?
First of all, they are a large and diverse family of natural antioxidants in our diet. They are found widely in vegetables, fruits, grains, but also tea, coffee and wine.
More than 8000 individual polyphenols have been identified. They can be divided according to their chemical structure. Phenolic acids, flavonoids, stilbenes and lignans are some of the most common groups.
A large portion of the polyphenols we consume are not absorbed in the upper intestines. Instead, they travel down to the large intestine, where most of them are metabolized by our gut bacteria. Here they are transformed to bioactive metabolites known to have the following beneficial effects on our gut health and overall well-being :
- Strengthen the connection between the cells in our intestines, which prevents bacteria or toxins from entering our bodies.
- Increase the production of mucus, which serves to defend against invading microbes.
- Stimulate the beneficial microbes in our gut to produce antimicrobial chemicals, which act as another layer of defense.
- Reduce the aggressiveness of our own immune system, to reduce inflammation in the gut.
- Positively modulate the gut microbiome by inhibiting bad microbes and increasing probiotic organisms in our gut.
The richest sources and our recommendations
The levels of polyphenols vary depending on the food source and the way the food has been prepared. It can also be affected by reacting with other chemicals in our food.
This makes it a bit challenging to give precise recommendations. But with this in mind, we have compiled a reference list of foods high in polyphenols:
1. Olive Oil
Consuming olive oil regularly, especially virgin olive oil (VOO), is associated with health benefits , such as reducing the development of atherosclerosis, diabetes, obesity, cancer, and neurodegenerative diseases (such as Alzheimer's).
This is partly due to its unique fatty acid profile, but VOO is also an excellent source of polyphenols, with concentrations ranging from 50 to 1000 mg/kg. The phenolic fraction of VOO also acts as a promoting factor for the well-being and growth of beneficial Lactobacillus species, and acts as an inhibitor of the growth of pathogenic bacteria .
Therefore, we recommend a daily consumption of approximately 40g, which corresponds to approximately 3 tablespoons.
2. Polyphenol boosters
In addition to olive oil, we have identified several foods that are super rich in polyphenols. We call these: polyphenol boosters.
We recommend consuming at least 2 or 3 servings/day of the richest sources, which help promote the growth of beneficial microbes.
Fermented foods
Fermented foods are defined as those foods that are produced by desired microbial growth and enzymatic processes. They are nothing new. In fact, they have existed for thousands of years and are very common in many cultures around the globe. They have become increasingly popular due to their potential health benefits, particularly mediated by the gut microbiota.
In addition to improving the taste, texture, and digestibility of our meals, fermented foods contain beneficial bacterial communities that inhibit pathogens and prevent spoilage microbes from growing in them. Fermenting food is said to increase the concentration of vitamins and bioactive compounds, increasing its nutritional value.
Fermented foods have the potential to increase the diversity of the ecosystem within us and reduce inflammation. A diverse microbiome is more resilient to change and able to function better.
We recommend at least 1 to 2 servings per day.
Conclusion
Polyphenols are a large group of antioxidants found in vegetables, fruits, spices and plant extracts. They have anti-inflammatory and anti-carcinogenic properties that help reduce the risk of developing serious diseases. They affect the gut flora in a number of ways that support beneficial bacteria. By eating plenty of plant-based products, you can benefit from these properties. Fermented foods can be part of a balanced and healthy diet because they contain beneficial microbes, which are known to have a number of health benefits, especially for the gut.
Author: Cecilia Clausen (Clinical Dietitian)
