Preservatives are used in the food industry to extend shelf life by inhibiting microbial growth and slowing chemical changes leading to spoilage. Some preservatives raise concerns about possible health effects, especially in relation to cancer. Experimental studies have shown that nitrates and nitrites used in processed meat can be converted in the body to N‑nitroso compounds, which are proven carcinogens in animals and potential carcinogens in humans. The European Food Safety Authority has recognized the risks of nitrates and nitrites and established acceptable daily allowances for them. In practice, however, there is a large consumption of industrially processed foods and significant differences in the content of additives between individual brands. In this context, in a linked study of 105,260 adults from the NutriNet-Santé cohort, Hasenböhler and colleagues comprehensively examined the association between exposure to food preservatives and cancer risk. The article emphasizes the need for a detailed assessment of these risks in real conditions of normal industrial food consumption.