Dietary supplementations to mitigate the cardiopulmonary effects of air pollution toxicity: A systematic review of clinical trials.
Level 1 - systematic review of randomized trials
Systematic review of clinical trials
PubMed 38870164 · doi:10.1371/journal.pone.0304402
What was done
A systematic review was conducted across PubMed/Medline, EMBASE, CENTRAL, and ClinicalTrials.gov for records up to March 31, 2023. The review evaluated clinical trials examining dietary supplements (such as fish oil, olive oil, vitamins, sulforaphane, L-arginine, N-acetylcysteine, and B vitamins) on cardiovascular outcomes (blood pressure, heart rate, heart rate variability, brachial artery diameter, flow-mediated dilation, lipid profiles) or pulmonary outcomes (lung function, airway inflammation) related to air pollution exposure.
What was found
From 4,681 identified records, 18 studies met inclusion criteria. The abstract provides no quantitative effect sizes or pooled numerical data. Qualitative findings showed contradictory results for fish oil and olive oil on cardiovascular endpoints, though fish oil provided limited evidence of protection against pulmonary dysfunction. Vitamin C alone largely failed to demonstrate cardiovascular benefits, whereas combining vitamins C and E protected against pulmonary dysfunction but yielded conflicting cardiovascular effects. Sulforaphane, L-arginine, N-acetylcysteine, and B vitamins showed potential benefits in a limited number of trials.
Why it matters
This review aggregates human trial evidence on nutritional countermeasures against air pollution toxicity. It clarifies that while antioxidant combinations and fatty acids show promise for pulmonary endpoints, evidence across cardiovascular outcomes remains heterogeneous.
Limits
The abstract provides no numerical data, pooled effect estimates, or formal risk-of-bias evaluations. The total evidence base is small, spanning only 18 trials divided among multiple distinct nutritional interventions and physiological endpoints. Optimal dosages, long-term safety, and broad efficacy remain undetermined.
Cited by
- supports Omega-3 supplementation has been shown in research to help blunt the adverse effects of air pollution.