Husband’s Bad Breath

I need help! My husband’s breath is so horrible. It’s always been a little different but as we’ve gotten older, it’s only gotten worse. We are only 35. He is a very healthy, clean man. I can even smell it right after he brushes his teeth. I have gotten a heighten sense of smell so maybe that’s why but it’s so hard to be intimate with him. Any ideas or do y’all know any medicines or vitamins I might can offer him?

Edited to add-he has been to the dentist. He goes regularly. He flosses occasionally. I do agree that he needs to see his doctor about it because it could be GI.