Despite the abundant sunlight, vitamin D deficiency is prevalent in South Asian countries including Bangladesh. Information on vitamin D level is insufficient in adults particularly in female garment workers in Bangladesh. This study was designed to evaluate the status of vitamin D, parathormone (PTH), calcium, and alkaline phosphatase (ALP) among the female garment workers in Bangladesh. Blood samples were collected from female garment workers (
Vitamin D is a fat soluble steroid hormone which plays an important role in maintaining normal level of calcium and phosphorus in blood. It promotes bone mineralization and is considered as an important determinant of bone health status through absorption of calcium and the secretion of parathyroid hormone (PTH) [
Vitamin D deficiency is prevalent in various parts of the world including South Asia [
Bangladesh is well known worldwide for its garments products. A large number of young female workers about 4 million worked in export based garment industries in Bangladesh. The female garment workers are mainly from rural areas with low socioeconomic background and they work typically 10–12 hours/day in an overcrowded and substandard environment [
Although a major part of garment workers in Bangladesh are young females, so far, only one study has been conducted to investigate the vitamin D status among them [
This study was conducted in an export-oriented garment factory located in a suburban area belonging to “The Immaculate Textile Ltd.,” Dhamrai, Dhaka, Bangladesh. The garment factory was a multistoried building which maintains a standard quality of working environment for the workers. A total of 80 blood samples were collected in April 2015 from the garment female workers (
Serum 25(OH)D was used to evaluate the vitamin D status among the study subjects. The laboratory analysis was carried out at the Department of Biochemistry, BSMMU. Serum concentration of 25(OH)D was measured by chemiluminescence microparticle immunoassay (CI 4100 ARCHITECT, USA). The intra- and interassay coefficients of variation (CV) were 6.5 and 7.4, respectively. The serum parathormone (PTH) was measured by chemiluminescence microparticle immunoassay (CI 4100 ARCHITECT, USA). The intra- and interassay CV for PTH were 6.8 and 5.4, respectively. Moreover, serum levels of alkaline phosphate activity (ALP) and calcium were also analyzed by chemiluminescence microparticle immunoassay (CI 4100 ARCHITECT, USA). The inter- and intra-assay CV for ALP and calcium analyses were less than 7%. Vitamin D deficiency was defined as a serum 25(OH)D level below 20 ng/mL and insufficiency as a serum 25(OH)D level of 21–29 ng/mL recommended by the Institute of Medicine 2011 [
The statistical analysis was carried out using the software IBM SPSS Statistics version 22. Data are presented as mean, median, and ranges of the parameters. Comparison between the groups was made by independent sample
In Dhamrai region of Dhaka district, the number of case and control female study subjects was equal. Their mean age was
Baseline demographic characteristics of study subjects.
Characteristics | All | Case | Control |
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( |
( |
( |
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Age (year) | 27.8 ± 5.1 | 27.2 ± 5.5 | 28.3 ± 4.6 | 0.32 |
Weight (Kg) | 52.2 ± 5.2 | 50.9 ± 5.6 | 53.5 ± 4.4 | 0.03 |
Height (cm) | 152.1 ± 5.1 | 151.3 ± 5.1 | 152.9 ± 4.9 | 0.78 |
BMI (Kg/m2) | 22.6 ± 2.4 | 22.2 ± 2.5 | 22.9 ± 2.2 | 0.23 |
Waist circumference (cm) | 72.1 ± 6.2 | 72.6 ± 6.6 | 71.6 ± 5.8 | 0.51 |
Hip circumference (cm) | 81.3 ± 5.4 | 81.9 ± 5.9 | 80.8 ± 4.8 | 0.38 |
Education level | ||||
≤primary | 30 | 20 | 10 | 0.68 |
Primary-junior level | 30 | 10 | 20 | |
≤secondary | 20 | 10 | 10 |
Values are presented as mean ± SD. Independent sample
The serum concentration of 25(OH)D reflects the nutritional status of vitamin D. The average level of serum 25(OH)D was significantly higher (
Categorization of study subjects depending upon vitamin D [25(OH)D] status.
Vitamin D | Case | Control |
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Deficient (<20 ng/mL) | 40 (100) | 7 (17) |
Insufficient (21–29 ng/mL) | 0 | 32 (80) |
Sufficient (≥30 ng/mL) | 0 | 1 (3) |
Serum vitamin D [25(OH)D] concentration was categorized according to Institute of Medicine (IOM) 2011.
Serum concentration of vitamin D [25(OH)D], PTH, calcium, and ALP in the study subjects.
Variables | Case ( |
Control ( |
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Mean ± SD | Median (range) | Mean ± SD | Median (range) | ||
25(OH)D (ng/mL) | 14.2 ± 2.6 | 14.3 (7.0–18.5) | 22.4 ± 2.4 | 22.1 (18.6–30.1) | <0.001 |
PTH (pg/mL) | 33.9 ± 17.2 | 32.6 (7.9–90.0) | 35.9 ± 16.3 | 34.5 (12.0–80.0) | 0.609 |
Calcium (mg/dL) | 9.1 ± 0.6 | 9.2 (7.5–10.0) | 9.3 ± 0.6 | 9.3 (7.5–10.5) | 0.057 |
ALP (U/L) | 117.2 ± 14.4 | 123.0 (80.0–135.0) | 80.5 ± 30.6 | 79.0 (36.0–125.0) | <0.001 |
There was no significant difference at the mean level of calcium and PTH between case (
Correlation of serum concentration of vitamin D [25(OH)D] with PTH (a), calcium (b), and ALP (c).
Based on information provided in the short food frequency questionnaires (FFQ), possible correlations were analyzed between serum 25(OH)D and food consumption in the cohorts. Serum 25(OH)D level was slightly high in more egg and fish consumption group. However, no significant difference was found within the groups (Table
Intake of vitamin D containing selected food and vitamin D levels among the study subjects.
Food items | Case | Control |
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Mean ± SD |
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Mean ± SD | ||
Egg consumption | |||||
Not at all | 5 | 12.4 ± 2.2 | 2 | 21.4 ± 2.1 | 0.152 |
1–4 times/month | 15 | 13.5 ± 2.4 | 10 | 22.1 ± 1.9 | |
1–4 times/weekly | 10 | 14.9 ± 3.1 | 15 | 22.6 ± 2.3 | |
1-2 times/day | 10 | 15.4 ± 2.6 | 13 | 23.1 ± 3.4 | |
Fish consumption | |||||
Less than 3 times/month | 10 | 13.9 ± 2.2 | 3 | 21.8 ± 3.2 | 0.459 |
1–6 times/week | 20 | 14.3 ± 2.6 | 25 | 22.4 ± 2.2 | |
1-2 times/day | 10 | 14.5 ± 2.9 | 12 | 22.7 ± 2.2 |
One-way ANOVA was used to find out the level of significance.
Vitamin D deficiency is prevalent in several parts of the world, but relatively a few studies have been carried out to investigate the vitamin D status in working populations. In Bangladesh, there is an insufficient information about vitamin D [25(OH)D] level in indoor female workers. The present study results indicate a high prevalence of vitamin D deficiency in female garment workers (100%) and low prevalence in female general workers (17%) in Bangladesh (Table
In present study, we noticed that the garment workers spent a major part of the day time (10–12 h/d) in the office building. In general, they have a regular sunshine exposure (5–15 min/d) in the very early morning on their way from living place to their working places [
The prevalence of vitamin D deficiency has been reported in different degrees in several countries in Asia. Low level of vitamin D has been reported in the adult population of Malaysia [
In present investigation, four in 80 participants had hyperparathyroidism (serum PTH > 65 pg/mL), which could not explain why serum PTH was increased in participants with low level of serum vitamin D [25(OH)D]. The present study findings comply with the report that low level of vitamin D does not always increase the serum PTH level [
In addition, a higher level of ALP was found in the study subjects and it was higher in case than the control group (Table
In the study, we found that the mean concentration of serum calcium was relatively low in case compared to control group. A lower level of calcium in garment workers has also been reported in the previous study [
The time of year is an important factor in measurement of vitamin D levels in the diagnosis of insufficiency or deficiency. A previous study found that summer is the ideal time to measure vitamin D levels as there is seasonal variation with a 14% increase of 25(OH)D concentrations in men in summer [
In our study, intake of selected vitamin D containing food did not show significant correlation with vitamin D. A similar finding was also found in Norris [
The present investigation evaluates the serum vitamin D status in female garment workers as well as female general workers in Bangladesh. The results indicate a high prevalence of vitamin D deficiency in the Bangladeshi female garment workers (100%) which could be a serious concern. Therefore, both governmental and nongovernmental health professional and health policy maker should pay attention to increase the awareness on vitamin D deficiency and its adverse effects on health especially in adult female garment workers in Bangladesh. A comprehensive programme including extensive awareness of the importance of sunlight exposure and improved dietary supplies of calcium and vitamin D as well as inclusion of food fortification is recommended to prevent the vitamin D deficiency in Bangladeshi women.
None of the authors have any conflicts of interest to declare.
The authors wish to thank the officials of the directory and Chief Medical Officer Dr. Hafizur Rahman of the “The Immaculate Textile Ltd.” for their valuable cooperation of the study. The authors are grateful to the volunteers for their participation. This study was partly supported by internal grant of BSMMU.