Think about frequency
Frequent sugary snacks and drinks give plaque bacteria repeated opportunities to produce acids. Instead of sipping a sweet drink throughout the day, consider water between meals. Check labels: drinks marketed as sports, energy or fruit beverages may contain substantial added sugar.
Sticky sweets can be difficult to clear from teeth. You do not need a perfect diet, but noticing when and how often you snack can reveal habits worth changing.
Build meals around variety
Choose a balanced mix of vegetables, fruit, protein, grains and dairy or suitable alternatives. Whole fruit is usually a more practical everyday choice than frequent juice. Water is a useful default drink, especially between meals.
Crunchy food does not replace brushing, and cheese or other foods do not erase the effect of sugar. Food choices work alongside cleaning rather than acting as a treatment for cavities.
Adapt the advice to your mouth
Braces, dentures, dry mouth, diabetes or recent dental work may change what is comfortable or appropriate. Discuss those needs with your dentist and, where relevant, your medical clinician or dietitian.
If you keep getting cavities, bring a typical day's food and drink pattern to your appointment. The timing of snacks, dry mouth, exposed roots and difficulties cleaning can all be part of the discussion. A tailored prevention plan is more useful than simply trying to brush harder.
Further reading
American Dental Association: Diet and dental health ↗
General education, not a diagnosis or an individual treatment recommendation. Ask your dental professional about your own care.