No mate, you need to learn that not everyone is suffering from the same condition, and that what may have worked for you will not work for everyone as people come here suffering from many many different types of ailments caused by various different causes and, if pathogenic, by many different species of pathogens, not all of which are intestinal.
You are indeed correct in saying that your immune system and gut flora does need to be looked after and body kept in good condition using common sense and healthy lifestyle, and the immune system will do an excellent job most of the time if your body is in good condition. However, while indeed good general advice to be cautious about, that is not the be-all-and-end-all, and your immune system is not invincible even with a healthy gut, and is incapable of eradicating certain parasites that have spent millions of years evolving sophisticated ways to survive along side it.
As someone who has suffered for years and do not want others to go through the length of suffering that I have, thinking that my own body would sort it out, when clearly I was not getting any better after trying out many many common-sense things. Only through trial-and-error (as well as developing additional distinct severe symptoms such as vomiting blood, ascites, breathing difficulties and a sensation of hundreds of things migrating around my body invoking me to do additional research) I stumbled upon drastic improvement after taking antihelmentics. If I were selling something I think I would have set up my own bloody website here in the UK rather than helping others out by recommending suppliers that I had success with on the other side of the world!