An unhealthy gut can cause many problems, starting with digestive issues or food intolerances but also less obvious things are controlled by big parts via you gut. This includes your mood, your energy levels, your weight or even your immune system.
The purpose of this blog is to provide you with five easy but scientifically proven ways to boost your gut health and thereby, improve your overall health and mood.
Before we start, I want to clarify that these tips probably work for most people but you might have reasons why something is not working for you. However, these tips are very easy to implement in your daily life, which means that you don’t need to follow a radical diet to live a healthy life.
So, let’s start with the first one:
Avoid processed foods
Obvious, right? Let me explain it quickly with some science, as we have learned that unless we know the “why” behind something, we probably won’t do it.
Processed foods are full of added sugar, artificial sweeteners and emulsifiers. Research over the last years has shown that these three by itself can have detrimental effects on the health of the microbiome. [1-7]
Maybe the biggest problem of processed foods is not even what is in it, but what is missing; Fiber.
Fiber is usually removed when food is processed to change the consistence, to make it taste better and to increase the shelf life . However, by removing the fiber we remove the food for our microbes and will potentially starve them.
Which brings me to the next point; Eat more fiber.
Eat more fiber
Fiber is more than just the indigestible part of food that helps us poop. Even though it does…help us poop.
Some people don’t do well on high amounts of fiber but most of us can benefit from increasing the fiber intake a little bit. The typical western diet is deprived fiber and even though the current dietary recommendations suggest a daily fiber intake of 30 grams but the average is barely at 15 grams per day. [8, 9]
Although we cannot digest fiber, our gut bacteria digest certain kinds of fiber, which they need it for growing and they show their gratitude by producing different molecules that are beneficial for us.
One group of molecules produced by our microbes are short-chain fatty acids (SCFAs). Science has shown that SCFAs play an important role in health and diseases, especially via their function to regulate the immune system and to provide energy to the cells that line the gut wall. [10-12]
Research also suggests that starving gut microbes start eating the mucus layer, which is a protective slimy substance that lines the inner walls of the intestine. The mucus layer prevents the direct contact of the trillions of microbes in our gut with the cells lining the gut, including the gut-resident immune cells. If bacteria get too close to the gut wall, they can set off alarm bells within the immune system.
This can ultimately lead to chronic inflammation and you really don’t want to have that. It had been shown over and over again that chronic inflammation can cause or aggravate almost any disease, including cancer, Alzheimer’s and heart diseases. 
Researchers found that just a couple days on a western style diet that is extremely low in fiber reduced the mucus layer extremely, but just adding back some fiber and probiotic bacteria could restore the protective mucus layer in a short time. [14, 15]
Some high-fiber foods that are good for the microbiome are:
But also Cacao (so dark chocolate might not be too bad for you. Just get the really dark version)
Eat a more diverse diet
The next advice would be to eat a diverse diet. We know that the diversity of our gut microbiome is one of the most important indicators for our health, but how do we get there? [16, 17]
Professor Tim Spector, author of the fascinating book “The Diet Myth” explains in his talk at the King’s College London what matters the most for a diverse microbiome:
In brief, he points out that eating a wide variety is the most important factor for maximum diversity and that this factor was more important than following any specific diet (vegan, vegetarien, etc)
An easy trick to increase the variety on your plate that has worked for me is that every time I go grocery shopping, I try to buy something I never had before or didn’t have in a long time. Some spices, some veggies or some fruits. Whatever it is as long as it is unprocessed. It might be you don’t like it but who knows… you might discover your new favorite food.
Of all the tips on the list, the next one might be the most controversial one. Include some probiotic food.
Some people say that probiotics don’t do anything, others say it is harmful and again others praise them as cure for all.
Well, obviously it is not a cure all. However, more and more scientific studies are released that show positive effect of either probiotics or fermented food on reducing inflammation, supporting the immune system, helping with weight loss, improving digestion, supporting the detoxification of the body, improving mood levels and many other things (including cancer and T2D).
People who eat a lot of yogurt appear to have more lactobacilli in their intestines. These people also have fewer Enterobacteriaceae, a bacteria associated with inflammation and a number of chronic diseases 
Supplementation with Lactobacilli casei improved diseases symptoms in patients with rheumatoid arthritis. The beneficial bacteria helped to regulate the immune system by lowering pro-inflammatory proteins and increasing anti-inflammatory ones .
A meta-analysis found that probiotics supplementation was associated with significant improvement in HbA1c and fasting insulin in type 2 diabetes patients 
I want to add that most microbes found in probiotic food or supplements don’t really stay in our GI tract for very long but they still seem to do something beneficial for us while they pass through and they can also change the overall microbial community on the way. [31-32]
I usually would recommend to get your probiotics from fermented food as this is easy, fresh and cheap and also provides the prebiotics – that is the food for the microbes.
Probiotics might not be necessary if you have a healthy gut community but there are so many factors that can disturb your gut health. Some examples are antibiotics, medication, heavy drinking or simply an unhealthy diet.
I am also aware that it is still a big debate to whether probiotics really help to resurrect the microbiome but I found that this helps very well for me. So, I wanted to give that tip here as well.
The science also seems to back this up to some extend: A review of 63 studies found mixed evidence regarding the efficacy of probiotics in altering the microbiome BUT their strongest effects appeared to be restoring the microbiome to a healthy state after being compromised. 
The last point on the list if probably the hardest for most people. It definitely is for me. Reduce your stress levels.
I am sure everyone knows this weird feeling in the gut before a test or a presentation. I don’t think we can avoid that and temporal limited stress is not the issue but chronic stress. I found that the only time I still experience gut issues is when I work under high pressure for a couple days. What helped me probably the most is to simply sit down with a fantasy book and let my mind wander in the imaginary world.
Two other things to reduce stress would be to go out into nature or play with some animals. Ever played with a dog or cat and still in a bad mood? I don’t think that’s even possible.
Playing with animals might also give your microbiome an extra kick. Researchers found that children who were exposed to dogs and cats during their first year of life experienced less allergies, which is probably due to the fact that the animals share some of their microbes. 
Okay that’s it. To sum up:
Avoid processed foods
Increase your fiber intake
Choose a wide diversity of food
Include some fermented food
Reduce your stress levels
If you want to add something extra: Exercise has also been shown to be good for the microbiome. [35, 36]
And, especially if you live in the USA, you might want to choose organic whenever possible. Some recent studies show that pesticides like glyphosate negatively affect the microbiome. [37-40]
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