Assessment of serum 25(OH)D concentration in women of childbearing age and their preschool children in Northern Jordan during summer

Abstract

Objective: To assess vitamin D status in women and their children aged 4-5 years in Northern Jordan during summer. Design: A cross-sectional study in which 93 mother-child dyads volunteered through local community centers between June and July 2007. Anthropometric measurements were performed and information on socioeconomic status, health issues, lifestyle factors and nutritional intake were obtained from mothers through a questionnaire. Main measures: Serum 25(OH)D and serum parathyroid hormone (PTH) levels were measured. Results: Mean age (s.d.) was 34.0 (6.0) years for mothers and 60.7 (5.4) months for children. Maternal body mass index (BMI) was 29.6 (5.6) kg/m 2 with 77% of women having a BMI X25 kg/m 2 . Mean concentration of serum 25(OH)D was 25.6 (9.6) nmol/l in mothers; only two women (2.2%) had 25(OH)D concentrations o12.5 nmol/l, but 48.9% of women had o25.0 nmol/l, and 97.8% of women had o50 nmol/l. No woman had values above 75 nmol/l. Children had higher (Po0.0001) serum 25(OH)D concentrations than did their mothers with a mean of 55.8 nmol/l. The children also had lower (Po0.0001) mean serum PTH concentrations than did their mothers (1.47 vs 3.12 pmol/l, respectively). Only three children had serum 25(OH)D concentration o25 nmol/l, but 39% (n ¼ 34) had 25(OH)D o50.0 nmol/l. Older women and those with five or more pregnancies had significantly reduced mean serum 25(OH)D concentrations. Children living in families with lower income had significantly higher mean serum 25(OH)D concentration as did children consuming fortified milk compared with those consuming non-fortified milk. Conclusion: Despite the abundant sunlight during summer, vitamin D status is a concern for mothers and children in Jordan.

Vitamin D Deficiency and Its Determinants in Adults: A Sample from Community-Based Settings in the United Arab Emirates

“…As for gender, most studies have reported that women had lower levels of vitamin D compared to men due to high body fat composition and the effect of childbearing [29]. Our results did not support such a claim—both men and women exhibited similar rates of vitamin D deficiency.…”

Predictors of vitamin D status and its association with parathyroid hormone in young New Zealand children

“…Although there is evidence for an inverse relation between 25(OH)D and serum PTH in older children and adolescents, estimates of 25(OH)D required for maximal suppression of PTH vary from 30 to 100 nmol/L (4,12,13,15,18,32). In our study, a serum 25(OH)D concentration of '61 nmol/L was needed to minimize PTH concentrations.…”

“…Studies assessing the association of serum 25(OH)D and PTH concentrations have been largely based on older children and adults (4,5,(12)(13)(14)(15)(16)(17)(18)(19). Little information is available about whether a plateau in PTH concentration is also evident in young children.…”

Prevalence and Predictors of Hypovitaminosis D Among Female University Students in Tabuk, Saudi Arabia

“…Prior research has emphasized that it is vital that individuals allow themselves sufficient exposure to sunlight to avoid vitamin D deficiency 37. On average, 5 to 10 minutes of direct exposure of limbs to sunlight (half the minimal erythema dose) produces approximately 3000 IU of vitamin D 3 3; however, the surface area of a person’s body exposed to direct sunlight depends on their choice of clothing, deployment of sunscreen, and general lifestyle 38. The high prevalence of vitamin D deficiency among Middle Eastern women has previously been associated with inadequate exposure of their skin to sunlight because of their countries’ conservative clothing customs, which specify that when outside they should wear items (eg, niqab, hijab) that cover most of their bodies 12,16,18.…”