Association between pre-pregnancy consumption of meat, iron intake, and the risk of gestational diabetes: the SUN project

Eur J Nutr. 2018 Apr;57(3):939-949. doi: 10.1007/s00394-017-1377-3. Epub 2017 Mar 11.


Purpose: We assessed the association of total meat, processed, and unprocessed red meat and iron intake with the risk of developing gestational diabetes mellitus (GDM) in pregnant women.

Methods: We conducted a prospective study among 3298 disease-free Spanish women participants of the SUN cohort who reported at least one pregnancy between December 1999 and March 2012. Meat consumption and iron intake were assessed at baseline through a validated, 136-item semi-quantitative, food frequency questionnaire. We categorized total, red, and processed meat consumption and iron intake into quartiles. Logistic regression models were used to adjust for potential confounders.

Results: We identified 172 incident cases of GDM. In the fully adjusted analysis, total meat consumption was significantly associated with a higher risk of GDM [OR = 1.67 (95% CI 1.06-2.63, p-trend 0.010)] for the highest versus the lowest quartile of consumption. The observed associations were particularly strong for red meat consumption [OR = 2.37 (95% CI 1.49-3.78, p-trend < 0.001)] and processed meat consumption [OR = 2.01 (95% CI 1.26-3.21, p-trend 0.003)]. Heme iron intake was also directly associated with GDM [OR = 2.21 (95% CI 1.37-3.58, p-trend 0.003)], although the association was attenuated and lost its statistical significance when we adjusted for red meat consumption [OR = 1.57 (95% CI 0.91-2.70, p-trend 0.213)]. No association was observed for non-heme and total iron intake, including supplements.

Conclusions: Our overall findings suggest that higher pre-pregnancy consumption of total meat, especially red and processed meat, and heme iron intake, are significantly associated with an increased GDM risk in a Mediterranean cohort of university graduates.

Keywords: Gestational diabetes mellitus; Heme iron intake; Mediterranean population; Red and processed meat; Total meat.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Cohort Studies
  • Diabetes, Gestational / epidemiology
  • Diabetes, Gestational / ethnology
  • Diabetes, Gestational / etiology*
  • Diabetes, Gestational / prevention & control
  • Diet / adverse effects*
  • Diet / ethnology
  • Dietary Supplements / adverse effects
  • Female
  • Follow-Up Studies
  • Heme / adverse effects*
  • Humans
  • Incidence
  • Iron, Dietary / adverse effects*
  • Maternal Nutritional Physiological Phenomena* / ethnology
  • Meat / adverse effects*
  • Meat Products / adverse effects*
  • Preconception Care
  • Pregnancy
  • Prospective Studies
  • Risk Factors
  • Self Care
  • Self Report
  • Spain / epidemiology
  • Young Adult


  • Iron, Dietary
  • Heme