I brush twice a day, I stay away from drinks that stay like coffee and teas (i drink tea occasionally), mostly do not eat hard candy..Outside of that, I get 2 cleanings a year.
But I think its genetics more than anything. No BS I have the goat dental health. I'm 33 and have never had cavities or mouth pains. My wisdom teeth came in perfectly and even improved my mouth structure in some ways. Those 10 months of invisalign in 2020 are the only reason brush 2x a day. And only got them to close a few gaps in my teeth and lessen my underbite.
Teeth whitning is overrated. I've tried it and very few ppl noticed. I've learned if your teeth are clean and straight, ppl will only see clean and straight teeth. Found that out when I closed my gap and no one could tell the difference. My teeth always looks white because I have dark skin