The people who have given advice know pretty well that is is from the inside of your body. Your digestive system is the inside, You may think it's just your mouth but guess what your mouth is attached to your stomach, and believe me we would all be surprised at how easy it is to digest stuff in our systems that we are not even aware of.
There are certain types of fish you can eat that if it has bacteria in it is is not even removed by cooking. Like I said some times our systems get off through fungal infections as well as Canidia and eating stuff with Ecoli.
I had taken some Iodine for my thyroid and it clogged my liver and caused a horrible smell. I had to stop taking it and since I started detoxing with dandelion and using the antifungals and taking acv my system is getting much, much better.
Probiotics may not be the answer for everything. But a lot of these people are speaking through their experiences. Maybe you should see a GI doc and see what they have to say, God bless.