New Study Links Common Food Preservatives to Increased Cancer Risk
A recent study has raised concerns about the potential health risks associated with certain preservatives commonly found in a variety of everyday food products. These include items like cured meats, toothpaste, salad dressings, ketchup, and mustard. The research, conducted by French scientists, highlights a possible link between these additives and an increased risk of developing cancer.
The study involved data from over 100,000 participants, with an average age of 42 and nearly 80% being women. Researchers tracked the dietary intake of various preservatives using detailed 24-hour dietary records over a period of 7.5 years. They then used health questionnaires and official medical and death records to monitor cancer cases from 2009 to 2023.
By the end of the study, 4,000 participants had been diagnosed with cancer, with breast, prostate, and colorectal cancers being the most common types. The team analyzed 17 different preservatives, including citric acid, lecithins, total sulphites, ascorbic acid, sodium nitrite, potassium sorbate, sodium erythorbate, sodium ascorbate, potassium metabisulfite, and potassium nitrate.
Their findings revealed no association with cancer incidence for total preservatives or 11 of the individual ones. However, several preservatives were linked to an increased risk of cancer. These included potassium sorbate, potassium metabisulfite, sodium nitrite, potassium nitrate, acetic acid, and sodium erythorbate.
Those who consumed higher amounts of these preservatives showed a greater likelihood of developing cancer compared to those with lower consumption levels. These preservatives are mostly non-antioxidants, used to extend the shelf life of food by preventing microbial growth or chemical changes.
For instance, potassium sorbate, which was associated with a 14% higher overall cancer risk and a 26% increased risk of breast cancer, is commonly found in dried meats, apple cider, baked goods, canned fruits and vegetables, cheeses, ice cream, pickles, and ice creams. Total sulphites, present in some processed meats, soft drinks, and jams, were linked to a 12% increased risk of overall cancer.
Sodium nitrite was associated with a 32% increased risk of prostate cancer, while potassium nitrate was linked to a 13% increased risk of overall cancer and a 22% higher chance of breast cancer. Total acetates were also associated with a 15% increased risk of overall cancer and a 25% higher risk of breast cancer. Acetic acid, often found in pickled foods and sauces, was linked to a 12% increased risk of overall cancer.
Among antioxidant preservatives, only total erythorbates and a specific type, sodium erythorbate, were found to be associated with a higher incidence of cancer.
The researchers emphasized that this was an observational study and does not directly prove that consuming these preservatives increases cancer risk. However, they noted that the study was large and long-term, and existing experimental data suggests potential adverse effects of several of these compounds. They have called on manufacturers to limit the use of unnecessary preservatives and encourage consumers to choose freshly made, minimally processed foods.
In their publication in The BMJ, the researchers concluded: “This study brings new insights for the future re-evaluation of the safety of these food additives by health agencies, considering the balance between benefit and risk for food preservation and cancer.”
Expert Reactions and Ongoing Concerns
Experts reacting to the findings acknowledge that the study does not prove causation but consider the observations “interesting.” Professor William Gallagher from University College Dublin highlighted the associations between higher intake of non-antioxidant preservatives and higher rates of overall cancer, breast, and prostate cancer. He noted that while the increased risks are modest (e.g., 10-30% increased risk), they could have significant population-level impacts.
Rachel Richardson from The Cochrane Collaboration added that the associations found were generally modest, and the margins of error mean the true effect could be very small.
As the debate continues, questions remain about the hidden culprits in so-called “healthy” foods and the potential impact of food additives on cancer risk. Researchers are urging further investigation into the long-term effects of these preservatives and advocating for clearer guidelines to protect public health.
