One of the more firmly established cautions covered on this site — not another wellness trend.
This page is general education, not a diagnosis. If you're dealing with persistent or severe symptoms, please see a doctor — lifestyle tracking can be a useful complement to medical care, never a substitute for it.
Nitrates and nitrites are compounds used to cure processed meats (bacon, deli meat, hot dogs) — they extend shelf life and give cured meat its characteristic colour and flavour, and also occur naturally in some vegetables like spinach and beets.
International health bodies have classified processed meat as a substance with sufficient evidence linking regular consumption to increased colorectal cancer risk — a notably firmer classification than exists for many other food-related claims discussed on this site, worth taking seriously rather than dismissing as another wellness trend.
The research concern is specifically about processed meat (cured, smoked, salted) — unprocessed red meat and the naturally occurring nitrates in vegetables are generally treated as a separate question in this research, not lumped in with the same level of concern.
A reasonable, non-alarmist takeaway: treating processed meat (bacon, deli meat, hot dogs) as an occasional food rather than a daily staple is well supported by the evidence — no need to eliminate it entirely for most people, but frequency is worth noticing.