A study in the British Medical Journal showed an 11% increase in cancer risk for every 10% increase in ultra processed foods.
This is where snack prep is crucial. Chop fruits & veggies twice per week. Grab and go with nuts, hummus, turkey, cheese, etc. If you get low blood sugar it makes it much more tempting to make a convenience food purchase.
Fiolet T, Srour B, Sellem L, et al. Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort. BMJ. 2018;360:k322.