A 105,000-person study published in The BMJ found that sodium nitrite — the preservative in bacon, deli ham, hot dogs, and pepperoni — is associated with a 32% higher risk of prostate cancer.
The research tracked participants for an average of 7.5 years, making it one of the largest diet-cancer studies ever conducted on food preservatives.
But sodium nitrite isn't the only preservative in the crosshairs. The same study found potassium sorbate — used in wine, baked goods, cheeses, and sauces — linked to a 26% higher risk of breast cancer and a 14% increase in cancer overall. Potassium nitrate, found in cured meats, was associated with a 22% higher breast cancer risk.
WHAT’S NEW
Here's what makes this different from the usual "processed food is bad" story. This wasn't a study about ultra-processed food broadly — it was specifically about preservatives, the chemicals added to food to extend shelf life. Researchers tracked 17 individual preservatives and found that several of the most widely used ones show meaningful associations with cancer across multiple cancer types.
The nitrites problem isn't new, but this data is. The World Health Organization classified processed meats as a Group 1 carcinogen in 2015. The NutriNet-Santé study, published January 2026 in The BMJ, adds significant weight to that finding — tracking actual brand-specific food intake across 105,260 participants rather than relying on broad dietary categories.
And these ingredients are everywhere. Sodium nitrite appears in virtually every cured or processed meat product on the market — it gives ham its pink color and hot dogs their shelf stability. Potassium sorbate is one of the most common preservatives in the food supply, appearing in packaged baked goods, shredded cheese, wine, condiments, and some dried fruits. Most people consuming these products have no idea.
The swap worth making:
You don't have to quit sandwiches — but reading the ingredient list takes 10 seconds. Look for "sodium nitrite" or "potassium sorbate" on the back of deli meats, packaged cheese, and baked goods. Brands like Applegate and Boar's Head Naturals sell nitrite-free deli meats at most major grocers. For baked goods and cheese, a shorter ingredient list is usually the signal you want.
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The Tox Report is an independent publication. We are not affiliated with any food, pharmaceutical, or supplement company. Content is for informational purposes only and does not constitute medical advice.