Reducing exposure to air pollutants remains a public health priority, but it isn’t always within an individual patient’s control. That’s why research is increasingly focusing on modifiable lifestyle factors that can influence a person’s vulnerability to the effects of pollution.
Among these factors, diet sits at the center: a high-quality eating pattern could help modulate the inflammatory and oxidative processes involved in damage from fine particulate matter and nitrogen oxides.
Fine Particulate Matter, Nitrogen Oxides, and the Risk of Chronic Disease
Air pollution, especially fine and coarse particulate matter (PM2.5 and PM10), is a major public health concern. Beyond the respiratory system, exposure to fine particles has been linked to an increased risk of cardiovascular, metabolic, neurological, and digestive diseases.
Because an individual’s ability to influence air quality is limited, interest is growing in lifestyle factors that can modify the effects of pollution. Among these, diet is biologically plausible given its links to inflammation, oxidative stress, and the gut microbiome.
The Meta-analysis
The authors analyzed 51 observational studies—including 30 cohorts, 20 cross-sectional studies, and one case-control study—conducted across Europe, Asia, and the Americas, involving nearly 10 million participants. The data primarily concerned exposure to PM2.5, PM10, and nitrogen oxides, while overall dietary quality was assessed using dietary-pattern models, individual foods, and nutrients.
Mediterranean Diet, Whole Grains, Dairy, and Omega-3s
Overall, for every 5 μg/m3 rise in particulate concentration, cardiovascular disease risk increased by about 7%. The association was less pronounced among individuals following dietary patterns deemed healthy, rich in fruits, vegetables, whole grains, and nuts, such as the Mediterranean diet.
A higher intake of cereals and dairy was associated with a more modest effect of particulates on blood pressure; by contrast, sugary beverages appeared to amplify the association. For chronic respiratory diseases, the relative risk increase linked to particulates (+20%) and nitrogen oxides (+7%) was attenuated by higher omega-3 intake and amplified by less healthy dietary patterns.
Also, the link between environmental pollution and metabolic diseases, such as diabetes and metabolic syndrome, appeared to be modulated by diet: risk rose by 19% for every 5 μg/m3 increase in PM and 13% for every rise in nitrogen oxides, but was mitigated in people with healthier diets and amplified by less healthy ones.
Pollution, the Brain, and the Digestive System: Evidence Still Limited
The evidence on brain and digestive health is more limited. Particulate matter was associated with a relative 9% increase in the risk of neuropsychiatric disorders and a 17% increase in the risk of digestive diseases.
A higher intake of B vitamins seemed to lessen the association between pollution and dementia, while a diet rich in fats appeared linked to a more marked risk of fatty liver disease.
Possible Biological Mechanisms: Inflammation, Oxidative Stress, and the Microbiome
According to the authors, diet could modulate the harm caused by pollution through plausible biological pathways: antioxidant and anti-inflammatory compounds, cereals, dairy products, omega-3s, and B vitamins may help improve endothelial function and curb inflammation, oxidative stress, and gut dysbiosis.
Limitations of Observational Studies
These observations do not prove a direct protective effect of diet: those who follow a healthier diet may also be more physically active, smoke less, live in less polluted areas, or have greater access to healthcare.
Even with appropriate statistical analyses, it isn’t possible to completely rule out confounding factors.
Additionally, the typical limitations of observational studies persist, including heterogeneity across populations and diseases studied and potential errors in estimating dietary intake.
Implications for Clinical Practice and Public Health
The study suggests that promoting healthy dietary patterns could help mitigate part of the health burden of air pollution. To define the true clinical relevance of this effect, targeted studies—potentially experimental and controlled—will be needed.
Study
Chen Y, Cai B, Wang F, et al. Dietary Intake Modifies the Association between Air Pollution and Chronic Diseases: A Systematic Review and Meta-analysis. Adv Nutr. Published online July 20, 2026. doi:10.1016/j.advnut.2026.100709
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