Many processed foods (mostly processed meats) have nitrates, which, according to some studies, are carcinogenic. However, some vegetables also contain nitrates. In some forms, nitrates and nitrites can be hazardous. However, they may also have health benefits.

You can check the label of processed meat for nitrites or nitrates in the ingredient list. If there are no added nitrates, the front label will say “Uncured.”

Should nitrates/nitrites be avoided? That’s for you to decide!

The Nitrate and Nitrite Myth
http://chriskresser.com/the-nitrate-and-nitrite-myth-another-reason-not-to-fear-bacon/

NOTE: “Adventist non-vegetarians” (who eat only “clean” meat) can eat turkey, chicken, or beef bacon, as well as beef hot dogs, beef pepperoni, turkey sausage, etc.

Dietary Nitrates, Nitrites, and Nitrosamines Intake and the Risk of Gastric Cancer: A Meta-Analysis
https://pubmed.ncbi.nlm.nih.gov/26633477/