Not OP, but in a similar situation. I'm 39, the last time a dentist looked in my mouth I was probably 16 or so* and I brush only once a day (after breakfast, which is the least effective over doing it before going to sleep). Never had a cavity. I don't think I have halitosis, at least the people I have kissed over the years never complained to me.
Being Italian, I eat pasta literally every day, and my daily breakfast is chocolate chip cookies.
My impression is that mouth health is 100% genetics and biome lottery.
* I have extreme mistrust in their profession, due to bad experiences. When I was a kid, I injured a milk tooth which turned black. The dentist shrugged and said that it would fall normally. It didn't and it fucked up all permanent teeth that sprouted in random directions in the area. Every single dentist surveyed to fix the problem requested gigantic payments (to the tune of tens thousands of dollars, this was in the 90s in Italy, so adjust for inflation and cost of living to know how crazy this was) without providing any result guarantees, so I kept my crooked teeth. It doesn't help dentistry in Italy is that profession where you mainly do tax evasion, and occasionally look into people mouths to pass the time.
41 here, and also not seen by a dentist since I was around 16. No cavities for now, that I know of. If I have any, they don't hurt, at least for now. Fingers crossed.
My diet is rather unremarkable, I don't consume a lot of sugar or sweets but don't refrain from them either. I brush 3 times a day. I do have occasional halitosis but it seems to be related to acid reflux, my breath seems to be fine when I have no reflux.
37 and same here. I brush twice a day with an electric toothbrush. I also brush my tongue well and rinse and gargle vigorously with water afterwards. I find I need to an electric toothbrush or I can't brush my wisdom teeth properly.
Last time I went to the dentist they removed 4 teeth because my mouth was crowded. Then I had braces. They came out when I was 16 or so and haven't been since.
I also spit several times a day. I don't know if this is relevant, but it seems to me it might be. At some point in my life I developed a habit, whenever I go to the toilet, I spit. My mouth actually salivates to get ready for it. I feel like it might do something to keep my mouth fresh.
I don't eat fruit. Very little sugar. I only eat within an 8 hour window each day. Lots of cheese. Every meal is balanced (plenty of fat to accompany any carbs, protein is incidental, I don't think about it).
Anecdata: all members of my nuclear family have crowded, crooked teeth. We all have a penchant for sweets across the day. My mom is 93 and has no cavities, but her A1c started reading for 6 in the last few years.
I'm 61 and have one filling. FWIW, offer the years, lots of dentists have found other cavities in my mouth, but no two dentists have ever found the same cavities...
Between the four of us in my family, there aren't even 5 fillings in our ugly teeth.
Being Italian, I eat pasta literally every day, and my daily breakfast is chocolate chip cookies.
My impression is that mouth health is 100% genetics and biome lottery.
* I have extreme mistrust in their profession, due to bad experiences. When I was a kid, I injured a milk tooth which turned black. The dentist shrugged and said that it would fall normally. It didn't and it fucked up all permanent teeth that sprouted in random directions in the area. Every single dentist surveyed to fix the problem requested gigantic payments (to the tune of tens thousands of dollars, this was in the 90s in Italy, so adjust for inflation and cost of living to know how crazy this was) without providing any result guarantees, so I kept my crooked teeth. It doesn't help dentistry in Italy is that profession where you mainly do tax evasion, and occasionally look into people mouths to pass the time.