Absence of vitamin D deficiency among common outdoor workers in Delhi.
Clin Endocrinol (Oxf). 2019 May 14. doi: 10.1111/cen.14012.
Dharmshaktu P1, Saha S1, Kar P1, Sreenivas V1, Ramakrishnan L1, Goswami R1.
1 Dept of Endocrinology and Metabolism, Cardiac Biochemistry and Biostatistics, All India Institute of Medical Sciences, New Delhi, 110029.
- International Conference of Vitamin D Fortification of Food (India) – Sept 2018
- Why India's vitamin D deficiency is grim - 40 pages Feb 2014
- Preterm labor 20 times more likely if low vitamin D, etc. (India) – Feb 2017
- Each hour of outdoor work in India increased vitamin D levels by 2 nanograms – March 2017
Reasons for the low vitamin D level include
- Very Dark Skins need 4X more sunshine to produce the same amount of vitamin D
- Protect against the hot sun by wearing hats and lots of clothes
- Diet
- Excessive Omega-6 (which blocks Omega-3)
- Lack of Magnesium n food and water (Mg essential in 8 stages of Vitamin D metabolism)
- Virtually no Vitamin D from food (especially for meatless diet)
- Zero Vitamin D fortification of food in India
- Air pollution greatly decreases the UVB needed to make Vitamin D
- Note: These people worked outdoors in cities (farmers have far less air pollution)
BACKGROUND:
There is reservation about accepting the notion of widespread vitamin-D deficiency (VDD) in sunny countries because information base is largely urban indoors and the cut-off serum 25(OH)D > 75.0 nmol/L to define sufficiency is perceived as high.
OBJECTIVE: We assessed the vitamin-D status of subjects engaged in six types of outdoors jobs with freedom to seek shade, when needed.
DESIGN: Descriptive observational study.
SUBJECTS AND METHODS:
573 outdoors, (hawkers, n = 144; autorickshaw-drivers, n = 113; manual-rickshaw pullers, n = 49; fuel-station attendants, n = 84; gardeners, n = 96; traffic-police personnel, n = 87) were assessed for serum 25(OH)D, iPTH and total calcium during summer and winter. Bank-employees were indoor controls (n = 72). Serum 25(OH)D was defined as sufficient if ≥ 50.0 nmol/L and deficient when < 30.0 nmol/L, as per 'Institute of Medicine'.
RESULTS:
Mean serum 25(OH)D of 573 outdoors was 44.8 ± 19.6 nmol/L and showed a physiological inverse-relation with iPTH (P < 0.001). 77.5% of the outdoors did not have VDD.
- Hawkers,
- gardeners,
- fuel-station attendants and
- rickshaw-pullers
had sufficient or near sufficient serum 25(OH)D. The mean serum 25(OH)D (30.6 ± 23.2 nmol/L) of indoors though lower by 12.7 nmol/L than outdoors, was above the cut-off of VDD. Proportions with supranormal iPTH were comparable between outdoors and indoors (14.0% vs. 20.8%). Despite winter dip the mean serum 25(OH)D (31.2 ± 14.3 nmol/l) of outdoors was not deficient.
CONCLUSIONS:
VDD is not universal. Most urban outdoor workers do not have vitamin D deficiency. This article is protected by copyright. All rights reserved.