I love mutts. Always have and always had one or two.
Sadly, the last two died of different types of cancer.
Dog food? Not sure, I always fed good food. Not the bottom, bargin basement stuff.
M last two were the best... I no longer believe that mutts are are “immune” thgan purebreds. Sad but true.
Mixed breeds are (mostly in the US) mixes of various purebreds, so they can be prone to the same health issues.