Study · Journal of diabetes research · 2024Conflicts declared

Vitamin C, heavy metals and gestational diabetes risk

What it found

In a case-control study in Taiyuan, China, women with higher blood levels of mercury and arsenic were more likely to have gestational diabetes, but this link was not seen in women who took vitamin C supplements or ate at least 85 mg of vitamin C a day.

What they found

Studies in people

Mercury and arsenic link

Women with higher blood levels of mercury or arsenic were more likely to have gestational diabetes. This was seen in women who did not take vitamin C supplements and ate less than 85 mg of vitamin C a day from food.

Vitamin C and no link

Among women who took vitamin C supplements or ate at least 85 mg of vitamin C a day from food, there was no significant link between mercury or arsenic levels and gestational diabetes.

Vitamin C alone

Vitamin C supplement use or dietary vitamin C intake by itself was not significantly linked to gestational diabetes.

Other metals

No significant links or interactions were found for the other metals measured (nickel, cadmium, antimony, thallium, and lead).

What the authors conclude

“Our study, for the first time, suggests that vitamin C supplement use or higher dietary vitamin C intake during preconception and early pregnancy could alleviate the risk of GDM associated with exposure to As and Hg.”
Wang Y, Wu W, Zhang P, et al, 2024

Also in their conclusions

  • They say their study suggests that vitamin C supplement use or higher dietary vitamin C intake during preconception and early pregnancy could alleviate the risk of gestational diabetes associated with exposure to arsenic and mercury.
  • They call for further research to validate the findings with a larger sample size and samples taken during pregnancy.

How it was done

Heavy metals may raise the risk of gestational diabetes through oxidative stress, and vitamin C is an antioxidant. The authors wanted to see whether vitamin C could change the link between metal exposure and gestational diabetes.

They compared 776 women with gestational diabetes and 776 without, all from the Taiyuan birth cohort in China. Vitamin C intake from diet and supplements was asked about for the year before pregnancy and the first trimester, and blood levels of seven metals were measured.

What it can’t tell you

  • This was a case-control study, so it can show links but cannot prove that vitamin C or metals cause or prevent gestational diabetes.
  • Metal levels were measured from blood samples taken at delivery, so the study cannot rule out reverse causality.
  • The number of women who took vitamin C supplements was small, so the results need confirmation in larger studies.

The paper

Title
Vitamin C Alleviates the Risk of Gestational Diabetes Mellitus Associated With Exposure to Metals
Type
Study
Evidence
Studies in people
Summarised from
Full text
Cite
Wang Y, Wu W, Zhang P, et al (2024). Vitamin C Alleviates the Risk of Gestational Diabetes Mellitus Associated With Exposure to Metals. Journal of diabetes research. doi:10.1155/2024/1298122Free full textPubMed 39035682DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error