I would like to share my story and tell you what has worked for me at last.
As far as I can remember, since my childhood, I suffered from bad breath. No matter how often I brushed my teeth, used mouthwash, or (as an adult) flossed after every tiny piece of food, the bad breath (and taste) came back after one hour or so.
I always was very self-conscious about this topic, and, over the years, I developed downright mental issues, like severe depression and some kind of social phobia. My social life was, of course, quite limited. I habitually chewed gum and I always made sure that I didn't have close contact with others. As a teenager, I even started smoking and drinking alcohol to "camouflage" the foul smell.
I was too ashamed to consult a doctor about it. But I had my tonsils removed at the age of twenty, and a wisdom tooth was removed in my early thirties. But this did not improve anything.
So the years went by, with flossing, all kinds of mouthwash, chewing gum, smoking, and drinking ( I very often found an opportunity to have a beer or two, or some cocktail).
Overall, I was not a very healthy person. I suffered from several severe allergies all year round, I often had sinusitis, plus I was a bit overweight, and I had some kind of binge eating disorder (self-diagnosis). (Perhaps because eating continually didn't make me notice the foul taste in my mouth?!
)Four years ago, I became interested in a healthier lifestyle. So I tried Yoga and eventually quit smoking and drinking (after 25 years!!!)
Nearly three years ago, I read the popular book "wheat belly: lose the wheat, lose the weight" by William Davis,
which was an international bestseller. I found it very convincing. According to the author, the so called "brain fog" (a certain dizzyness or numbness in the mind) is related to gluten sensitivity - even though a celiac testing might be negative! I chronically suffered from brain fog since my childhood! So I gave it a try and started a strict gluten-free diet.
In the following months, I began to feel much better! The brain fog vanished, my mind was much clearer. My allergies became less grave. And the best thing: the bad breath vanished and never came back!!!
In a popular German pharmacy journal, I found that celiac disease can indeed be a rare cause of bad breath. Herehttps://www.glutenfreesociety.org/denti ... ensitivity
an English article.
In early 2018, I went even one step further. Again inspired by a book - this time by Helmut Wandmaker, a German author - I started to follow a strict raw vegan diet, as the book promised miraculous benefits from that lifestyle.
With only one exception during a three-week holiday in Japan, I eat exclusively fruit, raw vegetables, and some nuts and oils. No spices, almost no salt, and no coffee.
What shall I say?
My breath (and other body odours) got even better! Even in the morning, my breath is fresh. My tongue, which used to be grey or white all the time, is now always a healthy pink.
Other benefits:
My allergies have completely vanished. I have lost a significant amount of weight. I am really athletic now, and I have a lot more energy. I never get sick (before I caught a cold quite easily). My mood stabilises more and more (I was depressive for years).
At last, I am "redeemed" from bad breath. This, plus the other benefits from the radical change of my diet, has made my life much better. It was really worth the effort.
! Once I made this decision, it wasn't too difficult to sustain... I just wanted to stay slim, fit, healthy, and pleasant smelling! 
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