Oral Presentation Joint Annual Scientific Meeting of the Nutrition Society of NZ and the Nutrition Society of Australia

Vitamin B12 status is lower in oral contraceptive pill users compared to non-users (228)

Jason Cocker 1 , Jill Haszard 1 , Fiona O'Leary 2 , Flavia Fayet-Moore 2 , Jennifer McArthur 2 , Samir Samman 1 2
  1. Department of Human Nutrition, University of Otago, Dunedin, Otago, New Zealand
  2. Discipline of Nutrition & Metabolism, School of Molecular Bioscience, The University of Sydney, Sydney, NSW, Australia

Background/Aims: Vitamin B12 deficiency has potentially serious lifelong consequences.The aim of this study is to explore the associations between markers of vitamin B12 status and other biochemical, dietary and physical measures.

Methods: Three data sets composed of young omnivore women (n=65; age 24.5 ± 4.4 y; mean ± SD), randomly selected young women (n=305; age 22.5 ± 3.9) and elderly women (n=44; age 80.5 ± 7.6) were examined. Associations between vitamin B12 biomarkers and other selected biomarkers of nutritional status (i.e. serum folate, erythrocyte folate), lifestyle factors such as; dietary intake, smoking, alcohol intake, oral contraceptive pill (OCP) use (in the non-elderly groups), and other factors such as BMI and age were examined using mixed effects regression, accounting for study clusters.

Results: Serum vitamin B12 concentration (pmol/L) was related positively to both serum folate (nmol/L) (B=0.018 95%CI: 0.009-0.026, p<0.001) and erythrocyte folate (nmol/L) (B=0.456 95%CI: 0.164-0.747, p<0.01). Younger women who used the OCP had serum vitamin B12 concentrations that were 72.3 (SE=12.4) pmol/L lower than non-users (p<0.001). Vitamin B12 was marginally associated with the intakes of both protein (p<0.05) and alcohol (p<0.001). Serum vitamin B12 concentration was not related to age, smoking status or iron status.

Conclusions: The association between vitamin B12 and folate status may be indicative of a higher diet quality, but requires further investigation. With vitamin B12 deficiency being linked with increased risk of neural tube defect, the use of the OCP may pose an increased risk in women of reproductive age.

Funding Source/s: NA