Vitamin D and folate may reduce the risk of mortality associated with plastic pollutants

Researchers from the Granada Institute for Biomedical Research (ibs.GRANADA) and the University of Granada, in collaboration with the Harvard School of Public Health and Peking University, have published an international study in the journal The Lancet Planetary Health, showing that people's exposure to endocrine disruptors present in plastics is associated with an increased risk of mortality.

At the same time, the results suggest that higher levels of vitamin D and folate in the blood could protect against the adverse effects of these pollutants.

The team analyzed data from more than 8.000 adults in the National Health and Nutrition Examination Survey (NHANES) in the United States. At the start of the study, participants' urine exposure to various endocrine disruptors was measured, including bisphenol A (BPA) and different phthalates used in food packaging, canned goods, plastics in general, and cosmetics. Using population-based registries, participants were followed for an average of eight years, and the date of death from cancer, cardiovascular disease, and any cause was recorded.

After considering multiple factors such as age, weight, socioeconomic status, and lifestyle habits, the results showed that those most exposed to the mixture of these plastic pollutants had a higher risk of death during the follow-up period: 35% higher from any cause, 73% higher from cancer, and 89% higher from cardiovascular disease. Based on these data, researchers estimate that this exposure could be responsible for up to 256.471 deaths per year in the United States (10% of annual deaths), a smaller contribution than that attributed to tobacco, but similar to that related to physical inactivity.

Marieta Fernández, lead researcher of the A15-Basic and Clinical Oncology group at ibs.GRANADA, professor at the University of Granada and co-author of the study, comments: “This work confirms one of the hypotheses that the Environmental Medicine group at the University of Granada has been investigating for more than three decades: the general population is exposed to complex mixtures of endocrine disruptors, and this mixture is responsible for various harmful effects on their health. However, regulatory agencies continue to assess and regulate the risk of these substances one by one, individually. To better protect the population, we need to regulate simultaneous exposure to families of compounds with similar physicochemical and biological characteristics, for example, the chemical compounds used in plastic materials that come into contact with food.”

A healthy diet and outdoor physical activity are essential to reducing the risk.

This study also reveals that the association between exposure to the mixture of plastic pollutants and an increased risk of mortality was observed only in participants with the lowest blood levels of vitamin D and folate, but not in those with the highest levels. This novel finding could pave the way for clinical trials to counteract the adverse effects of these environmental pollutants.

Vicente Mustieles, leader of the study and Miguel Servet researcher at ibs.GRANADA and the San Cecilio University Clinical Hospital of Granada, adds: “In line with the results of experimental studies in rodents, our results suggest that optimal levels of vitamin D and folate could help counteract the adverse effects of exposure to the mixture of plastic pollutants evaluated.” However, he warns: "The protective effect was mainly observed in those participants who did not take vitamin supplements, supporting the importance of improving levels of these vitamins through a dietary pattern that is predominantly plant-based, such as the Mediterranean diet, and an active lifestyle that includes walking and sufficient outdoor physical activity."

Impact in Europe and Spain

In response to whether these results in the North American population could be extrapolated to the European and Spanish populations, Marieta Fernández indicates that: “Exposure to these endocrine disruptors is practically universal, and in both the US and Spain, more than 90% of the population has measurable levels of these compounds in their urine. Studies in European populations have also linked exposure to these same endocrine disruptors with some of the chronic diseases that cause the greatest morbidity and mortality, such as cardiometabolic diseases and cancer.”

Regarding the implications of the study, Vicente Mustieles comments: “Regulatory agencies, such as the European Food Safety Authority (EFSA), have a crucial role to play in protecting the public. However, as has happened with the recent ban on bisphenol A in food packaging, their decisions sometimes come too late.”

Researchers recommend minimizing the consumption of ultra-processed foods that not only provide no nutrition, but are also a source of exposure to the contaminants studied. “We should focus on a dietary pattern that is rich in plant-based foods, such as vegetables, fruits, legumes, whole grains, and nuts. We should also prioritize glass and stainless steel containers and utensils, avoiding the use of plastic materials in contact with our food. Along with an active lifestyle and frequent but moderate sun exposure, we believe this would be the best strategy to reduce exposure to and counteract the adverse effects of the endocrine disruptors studied.”the authors of the study conclude.