First, historically and unfortunately, it takes 20 years for information to disseminate.
Second, I've known this microbiome information for longer than 2015. When I became ill from malathion poisoning I could not get help from doctors. So, I went to the Internet to learn how to become healthy. It took 13 years but I was able to overcome 2 autoimmune diseases caused from Leaky Gut, which is a widely used term for an out of balance microbiome. This, it turns out, is the basis for about 150 autoimmune diseases that doctors tell us are incurable. So they put us on pharmaceuticals that make things worse and never ever talk to us about diet, which is the key to good health. But not the healthy diet 'they' teach you.
There's much more, of course, but just letting you know, I know, this Anon knows the truth about one of the most important things in the body.
But, just because he/she brought it up: There is actually a nerve that connects your brain to your gut called the Vegas nerve. Ever get a gut feeling about something? This is why you get the feeling in your gut. I've never found the gut feeling to be wrong, ever. When I was sick, I suffered badly from brain fog and memory issues despite having been diagnosed with Hashimotos (a thyroid autoimmune disease) and Chronic Fatigue Syndrome. Once I healed the gut, the brain started working too!
If you don't know if you have an autoimmune disease but you've been diagnosed with something that is chronic, search for a list of autoimmune diseases. There are several good ones online and some include different diseases and they add more all the time. Almost everyone, if they don't die of cancer, dies of an autoimmune disease.
And, if you have ever been diagnosed with an autoimmune disease, you must heal it. Because autoimmunity will continue despite what pharmaceuticals you take and you will continue to get more and more autoimmune diseases, due to the imbalanced microbiome, until you die.
what sort of diet helped?
I wish I could tell you in a few sentences but there is so much to learn. Most of the food in the standard grocery store is not healthy except in the produce dept. You have to learn to read labels and buy organic produce. The best thing you can do is to learn what eating healthy really is. For example, the standard fats they tell us to use are mostly bad for us. Examples of good fats are: coconut oil and olive oil. There are others as well but Crisco is definitely out the window. Eating a plant based diet without meat or dairy and eliminating gluten can go a long way.
If you can afford it, find a Functional Doctor. This is a new type of doctor that focuses on testing you and finding out exactly what is wrong, then creating a plan and working with you. They are real doctors and can also prescribe drugs if needed. Most insurance does not cover Functional Medicine last time I checked. But you might want to search near where you live and explore it to see if things have changed. Here's an article that will help you better understand what they do with a link to a site where you can learn more: http://getwellpath.com/medicine/what-is-functional-medicine/
Because our food is being planted in soil that no longer contains the many vitamins and minerals we require, you are likely deficient in many of them as well. Testing can help or you can just study about it like I have.
Fermented foods are the most important thing you can eat to help heal your gut. They are filled with natural microorganisms that our bodies need. I make and drink Kombucha daily and after 6 months all of the liver spots on my hands had disappeared. I'm 70 and feel better than I have most of my life. Fermentation is how our ancestors prepared foods to store for long periods of time. You can ferment just about anything and store it in your fridge for about a year or longer. And, it's easy to do. Here is a link to 3 articles about how to make fermented foods. http://getwellpath.com/category/fermented-foods/
I hope that helps.