Vitamin B status and metabolic health in women of reproductive age: Population-based biomarker survey.

BACKGROUND AND AIMS

In clinical populations, vitamin B deficiency has been associated with adverse metabolic health (e.g., gestational diabetes). Population-level data among women of reproductive age could inform screening and interventions. The objective of this analysis was to examine the prevalence of adverse metabolic characteristics (elevated adiposity and central adiposity, hypertension, elevated glycated hemoglobin [HbA1c]) and associations of vitamin B status with metabolic characteristics in women as part of a population-based biomarker survey in Southern India.

METHODS

Participants (n = 980 women 15-40 y; not pregnant or lactating) were assessed for total vitamin B, holotranscobalamin, methylmalonic acid, homocysteine, and HbA1c. Categorical anthropometry assessments and bioelectrical impedance analysis (e.g., whole body (WF%) and trunk (TF%) fat) were assessed among adults (≥18 y). Linear and binomial regressions were used to examine associations of vitamin B status with metabolic characteristics.

RESULTS

Overall, 25 % of participants had HbA1c ≥5.7 % (HbA1c ≥5.7-<6.5 %: 20.0 %; ≥6.5 %: 5.0 %), and 18.6 % had hypertension (Stage 1: 16.4 %; Stage 2: 2.2 %). Among adults, 23.4 % had body mass index of (BMI) 25.0-<30.0 kg/m, 9.6 % had BMI ≥30.0 kg/m, 13.4 % had elevated waist circumference (WC; >88.9 cm), and 20.8 % had elevated waist-hip ratio (WHR; ≥0.85 cm). Overall, higher vitamin B concentrations were associated with lower BMI and WC. Among adults, higher vitamin B concentrations were associated with lower WF% and TF%; and lower prevalence of overweight (BMI ≥25.0 kg/m) and elevated WC, WHR, and WF%. Similarly, vitamin B <148 pmol/L was associated with higher BMI and WC overall and, among adults, higher WF% and TF%, and increased overweight (BMI ≥25.0 kg/m; prevalence ratio: 1.31; 95 % confidence interval: 1.09-1.58), and elevated WC (>88.9 cm; 1.85 [1.32-2.60]), WHR (≥85.0; 1.38 [1.07-1.78]), WF% (>35 %; 1.29 [1.10-1.51]), and TF% (>35 %; 1.25 [1.06-1.49]).

CONCLUSIONS

The burden of adverse metabolic characteristics was substantial in this population of young, apparently healthy women. Among those with vitamin B <148 pmol/L there was increased central adiposity and overweight status. Evaluating vitamin B and metabolic outcomes prospectively could inform screening and interventions to improve women's health.

REGISTRATION NUMBER

NCT04048330.