The aim of this study was to examine the relationship between main air pollutants and all cancer mortality by performing a meta-analysis. We searched PubMed, EMBASE (a biomedical and pharmacological bibliographic database of published literature produced by Elsevier), and the reference lists of other reviews until April 2018. A random-effects model was employed to analyze the meta-estimates of each pollutant. A total of 30 cohort studies were included in the final analysis. Overall risk estimates of cancer mortality for 10 µg/m³ per increase of particulate matter (PM)_2.5, PM₁₀, and NO₂ were 1.17 (95% confidence interval (CI): 1.11–1.24), 1.09 (95% CI: 1.04–1.14), and 1.06 (95% CI: 1.02–1.10), respectively. With respect to the type of cancer, significant hazardous influences of PM_2.5 were noticed for lung cancer mortality and non-lung cancer mortality including liver cancer, colorectal cancer, bladder cancer, and kidney cancer, respectively, while PM₁₀ had harmful effects on mortality from lung cancer, pancreas cancer, and larynx cancer. Our meta-analysis of cohort studies indicates that exposure to the main air pollutants is associated with increased mortality from all cancers.

Lee DC, et al. Yonsei Med J. 2005 Aug;46(4):471-479. http://dx.doi.org/10.3349/ymj.2005.46.4.471

Evidence regarding the effect of fruit and vegetable consumption on metabolic syndrome remains inconclusive. Using MEDLINE, EMBASE, and Cochrane, we searched for relevant studies published before 10 December 2013. Of the 383 articles identified, eight randomized controlled trials with 396 participants (205 in intervention groups and 191 in control groups) were included in the final analyses. Fruit and vegetable intake was associated with a reduction in diastolic blood pressure (standardized mean difference: −0.29; 95% confidence interval: −0.57 to −0.02; p = 0.04); however, such intake did not affect waist circumference, systolic blood pressure, fasting glucose, high-density lipoprotein cholesterol, and triglyceride levels in metabolic syndrome patients. In a subgroup analysis, there were no statistically significant differences found according to the intervention period and provision type. Our results suggest an inverse association between fruit and vegetable consumption and diastolic blood pressure in metabolic syndrome patients.