Hi T 1986,
I had the same problem as you for 35 years. I thought it was my body but it wasn't. I even came to this forum years ago. I thought it was TMAU and just accepted it was something I may have to live with.
Well God is a good God. I do find out I had a probleme with gum disease. I hadn't beeen to a dentist on a regular basis only to get teeth pulled that were bad. After wanting to get some liners I got my teeth examined.
Anyway to make a long story short. I went to YT and online but I would mix bottled water, peroxide,baking soda,and a little bit of mouth rinse in a container and rinse several times a day.
Tea tree oil and water is good too but do not swallow it cause tea tree oil isn't good for swallowing.
I did find a product online but I cannot post it here. If u email me I can let u know. I don't sell or endorse anything. The lord just put it on my heart to share.