The Hidden Risks of Food Preservatives
Recent research has uncovered a potential link between the consumption of food preservatives and an increased risk of heart disease. These additives, commonly found in everyday products such as yoghurts, fruit juices, wholegrain bread, and many other processed foods, may significantly impact cardiovascular health.
French scientists conducted a study that revealed individuals who consumed the highest levels of preservatives were 16% more likely to suffer from heart disease, heart attacks, and strokes. They were also nearly 30% more likely to develop high blood pressure, a major risk factor for stroke. The researchers identified eight of the 17 most commonly consumed preservatives as directly contributing to elevated blood pressure.
The study, published in the European Heart Journal, involved nearly 112,400 participants. Anaïs Hasenböhler from Université Paris Cité highlighted the importance of this research, stating that while experimental studies have suggested some preservatives could be harmful, there was a lack of human evidence. She emphasized that this was the first study of its kind to explore the relationship between a wide range of preservatives and cardiovascular health.
During the study, participants were followed for an average of seven to eight years. They completed food and drink questionnaires every six months, detailing their consumption over the previous three days. Almost all participants, 99.5%, consumed at least one food preservative within the first two years of the study. However, the increased heart risk was only observed in those with the highest intake.
The lowest consumers averaged about 156mg of preservatives daily, while the highest consumed over 1g. Although the study did not provide detailed dietary examples of the highest consumers, it noted that they consumed significantly more ultra-processed foods, which made up 21.4% of their diet by weight, compared to 14.3% for the lowest consumers.
The primary sources of these preservatives included processed meats, packaged breads and cereals, processed fruits and vegetables, alcoholic drinks, and other packaged foods and drinks. The increased heart risk was attributed to eight specific preservatives, including potassium sorbate, potassium metabisulphite, sodium nitrite, and ascorbic acid. These additives are commonly used to extend shelf life and are present in a wide range of products, from baked goods to fruit juices and ice cream.
While the exact mechanism by which these additives increase heart risks remains unclear, the researchers suggested that preservatives might trigger oxidative stress, a form of cellular damage associated with inflammation, aging, and disease. However, as this was an observational study, no definitive cause-and-effect conclusions could be drawn.
The researchers concluded that regulatory authorities, such as the EFSA in Europe and the FDA in the USA, should re-evaluate the risks and benefits of these food additives. They also supported existing advice to prioritize fresh and minimally processed foods, such as fruits, vegetables, fish, legumes, and fibre-rich foods, to help prevent high blood pressure and heart disease.
They emphasized the role of healthcare professionals in educating the public about these risks. Independent experts welcomed the study but urged caution, noting that it does not prove preservatives directly cause heart disease. Rachel Richardson, a public health researcher not involved in the study, pointed out that higher preservative consumption might correlate with less healthy lifestyles, which could explain the increased ill-health.
Despite these concerns, she acknowledged that the findings warrant further investigation. Richardson also noted that the study was conducted in France and mainly involved women with healthier lifestyles than the general population, suggesting the results may not fully apply to the UK.
Other experts highlighted the importance of preservatives in ensuring food safety, extending shelf life, and reducing costs. In the UK, food additives are regularly reviewed by regulators, and unsafe substances can be removed from the market.
Professor Gunter Kuhnle of the University of Reading stressed the importance of research into additives but warned that studies must carefully distinguish the effects of preservatives from broader dietary habits that may negatively affect health.
High blood pressure affects around 14 million adults in the UK and is a leading cause of heart attacks and strokes. Often referred to as a ‘silent killer,’ it typically presents no symptoms, leaving many unaware of their condition until serious complications arise.
