"Everything in moderation" or "there are no bad foods" are nonsensical terms espoused by the food industry to justify eating their industrial sludge.

Random rare genetic cancers may not be preventable. But if you model your diet based on what humans evolved to eat, you'll be metabolically healthy. If you are metabolically healthy, you remove the risk of a whole plethora of health conditions including cancer.

Also, most nutritional studies are observational and based on weak data. Outcomes are often nothing better than random. We dont take nutritional advice from nutritionists.