# Fine Dust Tied to Lighter Babies Mainly Without Early Folic Acid

_Evidence Level: Moderate · Ge Y et al., Environment & health (Washington, D.C.), DOI 10.1021/envhealth.5c00779_

*Preconception Folic Acid Supplementation Associated with Attenuated Effects of Air Pollution on Birthweight Outcomes.*

- **Evidence Level**: Moderate
- **Why this grade**: A large observational study of 10,579 mother-child pairs; folic acid was not assigned, and air pollution was only estimated at home addresses.
- **Facts**: Design: Prospective cohort study · Funding: National Institute of Environmental Health Sciences; National Basic Research…
- **Publication Types**: Journal Article
- **Journal**: Environment & health (Washington, D.C.)
- **Sample Size**: 10,579 mother-child pairs in Shanghai, China
- **Authors**: Ge Y, Zhang Y, Liao J, Lin Y, Yang Z, Berhane K, Bai Z, Han B, Xu J, Gilliland F, Chen Z, Yan W, Huang G, Zhang JJ
- **Graded and published**: 2026-06-27
- **Last edited**: 2026-10-23
- **Topics**: Supplements, Women's Health, Air Pollution
- **DOI**: https://doi.org/10.1021/envhealth.5c00779
- **Free full text**: https://pmc.ncbi.nlm.nih.gov/articles/PMC13681435/
- **Original Source**: https://pubmed.ncbi.nlm.nih.gov/42903402/

## Summary

Low birthweight is among the leading reasons children under five die or fall ill worldwide. A large study from Shanghai found that dirty air during pregnancy was linked to lighter babies mostly in women who had not taken folic acid before conceiving. In women who took it early, that link was hard to see.

Researchers analysed data from 10,579 mothers and their children. Taking folic acid early meant using it, alone or in a multivitamin, in the three months before conception. The team estimated fine dust levels at each home with computer models. Without early folic acid, babies weighed 62.8 grams less on average for every extra 10 micrograms of the finest dust per cubic metre. They were also more often small for their stage of pregnancy. With early folic acid, no clear link showed up. The difference was stronger in boys than in girls.

The authors see early folic acid as a possible shield. The study cannot prove that, because the women were only observed. Most of them also took folic acid during pregnancy. Whether folic acid before conception alone is enough could not be tested, and no dose information was available.

## Practical Takeaway

Without folic acid before conception, more fine dust was linked to lighter babies; with early folic acid, no clear link showed up.

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_Canonical: https://longevity-cities.com/en/research/fine-dust-tied-to-lighter-babies-mainly-without-early-folic-acid · Part of Longevity Cities · Updated 2026-10-23_