Food preservatives thought of as ‘natural’ linked to high blood pressure and heart disease

Study Reveals ‘Natural’ Food Preservatives Linked to Cardiovascular Risks

Food preservatives thought of as natural – A recent investigation conducted by researchers in France has uncovered a connection between commonly used food preservatives and an increased likelihood of developing cardiovascular conditions, including high blood pressure and heart disease. The findings, published in the European Heart Journal, suggest that even preservatives labeled as ‘natural’ may contribute to these health risks. For instance, antioxidants like citric acid and ascorbic acid—often associated with freshness in fruits—were found to raise the risk of elevated blood pressure by 22% in individuals consuming more processed foods containing these additives.

The study, part of the NutriNet-Santé research initiative, tracked the dietary habits of over 112,000 participants aged 15 and older. Each volunteer documented their meals and beverages by brand name every three days over a period of six months, enabling researchers to analyze long-term consumption patterns. By cross-referencing this data with medical records from the French national healthcare system, the team identified the impact of 58 different preservatives on cardiovascular health. Among these, 17 were selected for deeper examination based on their prevalence in the diets of at least 10% of participants.

“Naturally occurring ascorbic acid and added ascorbic acid—whether chemically synthesized or extracted—may have distinct effects on the body,” explained Mathilde Touvier, the study’s senior author and director of research at France’s National Institute of Health and Medical Research. “This means the health outcomes observed for these preservatives aren’t necessarily the same as those from natural sources like fruits.”

Among the preservatives under scrutiny, eight were associated with a significant rise in blood pressure over a 10-year period. Three of these—potassium sorbate, potassium metabisulphite, and sodium nitrite—belong to a category of non-antioxidant preservatives, which primarily function to inhibit bacterial growth and spoilage. While potassium sorbate is frequently used in products such as wine, baked goods, and cheeses, potassium metabisulphite releases sulfur dioxide when dissolved, commonly found in juices, wines, and fermented beverages. Sodium nitrite, a chemical salt, is prevalent in processed meats like bacon, ham, and deli products.

The research also highlighted a broader concern about ultraprocessed foods (UPFs), which have been previously linked to a 50% higher risk of cardiovascular disease-related mortality. Additionally, these foods may elevate the chances of obesity by 55%, sleep disorders by 41%, and type 2 diabetes by 40%. Since these conditions are closely tied to heart health, the findings underscore the potential role of preservatives in amplifying their negative effects.

“This is one of the first large studies to examine individual preservatives rather than treating ultra-processed foods as a single entity,” noted Tracy Parker, a nutrition lead at the British Heart Foundation. “UPFs have long been scrutinized for their high content of sugar, salt, and fat, but these factors alone have never fully explained their greater harm compared to their nutrient profile.”

Parker emphasized that the new study helps bridge that gap by isolating the specific contributions of preservatives. The research aligns with the recent consensus from the European Society of Cardiology, which has identified ultraprocessed foods as a major public health challenge. However, the study also revealed that preservatives are not confined to ultraprocessed items. According to Anaïs Hasenböhler, the lead author of the research, prior studies by her team found that ultraprocessed foods accounted for only 35% of all preservative-containing foods in the average diet. This implies that preservatives are widespread, appearing in various food categories.

“There is no single food group that can be removed to eliminate the risk,” Hasenböhler stated in an email. “Preservatives are embedded in the everyday foods people consume, making it necessary to consider their cumulative impact.” The researcher recommended a shift toward minimally processed options, stating that consumers should prioritize fresh, uncooked, or frozen foods. “Frozen items are preserved through low temperatures, which may not always require the addition of chemical preservatives,” she added.

The study’s methodology involved analyzing a database of product ingredients, which allowed researchers to categorize preservatives and track their usage over time. Participants were asked to record every food and drink they consumed, including brand names and quantities, which provided detailed insights into preservative exposure. The data was then compared with medical outcomes, such as instances of heart attacks, strokes, and hypertension, to determine correlations.

While the study did not establish a direct causal link between preservatives and heart disease, it identified a significant association. For example, individuals who consumed higher amounts of potassium sorbate, a preservative used in dairy and sauces, showed a 29% greater risk of elevated blood pressure. Similarly, sodium nitrite, often used in cured meats, contributed to a 16% higher likelihood of heart attacks or strokes. These results suggest that even small amounts of certain preservatives may accumulate over time, influencing cardiovascular health in measurable ways.

“The findings support the recommendations to favor non-ultraprocessed foods,” Hasenböhler said. “Consumers should aim for fresh produce, unprocessed grains, and frozen options that rely on natural freezing rather than chemical additives.” This advice resonates with existing dietary guidelines that advocate for whole foods as a foundation for healthy eating. However, the study also raises questions about the safety of ‘natural’ preservatives when used in industrial quantities.

Touvier added that the study’s results do not discredit the benefits of naturally occurring antioxidants in fruits and vegetables. “While these substances can be found in unprocessed foods, their role as preservatives in packaged products may differ,” she said. “It’s possible that the way they’re applied in food manufacturing affects their health impacts.” This distinction is crucial for consumers seeking to make informed choices about their diet.

As the popularity of convenience foods continues to rise, the implications of this study are particularly relevant. Ultraprocessed foods are often marketed as healthy or natural, yet they contain additives that may subtly increase the risk of chronic diseases. By highlighting the specific preservatives linked to poor cardiovascular outcomes, the research provides a clearer picture of which ingredients to watch for. For example, sodium nitrite and sulfur-based compounds, which are already known to contribute to heart disease, now have further evidence supporting their role in elevating risk.

The findings also encourage a broader conversation about food labeling and consumer awareness. Many products label their preservatives as ‘natural’ to appeal to health-conscious buyers, but the study suggests that these terms may not always reflect the preservatives’ true impact. As Parker noted, “These results add another layer to the understanding of why ultraprocessed foods are more harmful than they initially appear.” The study serves as a reminder that even seemingly healthy ingredients can have unintended consequences when used in excess.

With over 112,000 participants contributing to the research, the study’s scale strengthens its credibility. The NutriNet-Santé project, which has been analyzing dietary patterns in France since 2009, offers a unique opportunity to study the long-term effects of preservatives. By linking individual additives to health outcomes, the research paves the way for more targeted interventions and dietary recommendations. As the debate over food processing continues, this study highlights the importance of scrutinizing not just the overall category of ultraprocessed foods but the specific components within them.

Ultimately, the research urges a reevaluation of preservative use in food production. While these additives serve important functions in preserving shelf life and safety, their potential health risks cannot be ignored. As the study’s authors emphasized, the goal is not to eliminate all preservatives but to understand their role in the broader context of diet and health. This insight could lead to more informed consumer choices and improved food labeling practices, helping to reduce the hidden dangers of everyday meals.