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.