The modifiable effect of vitamin D in the association between long-term exposure to ambient air pollution and glycosylated hemoglobin in patients with hypertension
Nutrition . 2022 Nov 29;107:111920. doi: 10.1016/j.nut.2022.111920
Lulin Wang 1, Ziyi Zhou 1, Dankang Li 2, Mingyang Wu 1, Yingping Yang 1, Yonghua Hu 3, Youjie Wang 1, Yu Sun 4, Yaohua Tian 5
Objectives: Evidence on the association between long-term exposure to ambient air pollution and serum glycosylated hemoglobin A1c (HbA1c) is limited and inconclusive. In addition, whether vitamin D can modify the association between air pollution exposure and glucose metabolism has not been previously investigated. We aimed to evaluate the effects of various air pollutants on serum HbA1c levels in patients with hypertension and, further, to explore the modification effect of individual serum vitamin D levels.
Methods: This study was derived from UK Biobank study, and 246 027 participants with hypertension were included in our analysis. Individual exposures to particulate matters (PMs) and nitrogen oxides were estimated using the land use regression model. The associations between air pollutants and HbA1c were assessed using the multivariable linear regression model. Among the 222 845 participants with a measurement of serum vitamin D, we explored the associations in subgroups stratified by vitamin D levels.
Results: Long-term air pollutant exposures were significantly associated with higher HbA1c levels. After adjusting for potential confounders, 10-µg/m3 (or 1-m-1) increases in concentrations of PM with diameters =2.5 µm (PM2.5), PM with diameters =10 µm, PM with diameters from 2.5 µm to 10 µm, PM2.5 absorbance, nitrogen oxides, and nitrogen dioxide were significantly associated with 0.59 (95% confidence interval, 0.28-0.89), 0.49 (0.33-0.65), 0.81 (0.48-1.14), 0.56 (0.44-0.69), 0.06 (0.04-0.09), and 0.16 (0.12-0.21) mmol/mol increase in serum HbA1c levels, respectively.
The associations were weakened but remained significant after additional adjustment of vitamin D.
In addition, the associations of air pollutants with HbA1c were more evident in participants with low serum vitamin D levels (all P values for interaction <0.001).
Conclusions: Long-term exposures to ambient air pollutants were associated with higher levels of HbA1c in a dose-response fashion in a large UK cohort. Serum vitamin D status significantly modified these associations, and high serum vitamin D levels may attenuate the relationships between air pollution exposures and HbA1c levels.
VitaminDWiki - Air Pollution reduces Vitamin D contains
Fact: Pollution reduces the amount of time that people are outdoors
Fact: Pollution is often associated with hot temperatures - another reason to not go outdoors
Fact: Less time outdoors results in lower Vitamin D levels
Fact: Pollution attenuates the amount of UVB getting to the skin (but by only a few percent)
Fact:The body's ability to fight Irritation/Inflammation is aided by vitamin D
Fact: All of the types of PM2.5 deaths are also associated with low vitamin D
Conclusion: Vitamin D supplementation helps the body fight the effects of pollution.
- There were 60+ references in Air Pollution reduces Vitamin D page as of June 2023
- Inhaled vitamin D might turn out to be especially good form as it goes directly to the lungs.