Vitamin D deficiency in western dwelling South Asian populations: an unrecognised epidemic

Abstract

Vitamin D deficiency (25-hydroxyvitamin D; 25(OH)D) is at epidemic proportions in western dwelling South Asian populations, including severe deficiency (<12⋅5 nmol/l) in 27–60% of individuals, depending on season. The paper aimed to review the literature concerning vitamin D concentrations in this population group. Research from the UK and Europe suggests a high prevalence of South Asians with 25(OH)D concentration <25 nmol/l, with most having a 25(OH)D concentration of <50 nmol/l. In Canada, South Asians appear to have a slightly higher 25(OH)D concentration. There are few studies from the United States, South Africa and Australasia. Reasons for vitamin D deficiency include low vitamin D intake, relatively high adiposity, sun exposure avoidance and wearing of a covered dress style for cultural reasons. Possible health effects of deficiency include bone diseases such as rickets and hypocalcaemia in children and osteomalacia in adults. Vitamin D deficiency may also increase the risk of other chronic diseases. Increased fortification of food items relevant to South Asian groups (e.g. chapatti flour), as well as increased use of vitamin D supplements may help reduce this epidemic. Introducing culturally acceptable ways of increasing skin exposure to the sun in South Asian women may also be beneficial but further research is needed to assess the effectiveness of different approaches. There may be a need for a South Asian specific vitamin D dietary intake guideline in western countries. To conclude, vitamin D deficiency is epidemic in South Asians living in western countries and there is a clear need for urgent public health action.

Vitamin D and COVID-19: evidence and recommendations for supplementation

“…A meta-analysis of 394 cross-sectional studies showed a correlation between vitamin D levels and latitude in Caucasians (−0.69 ± 0.30 nmol l −1 per degree, p = 0.02), but not for non-Caucasians (0.03 ± 0.39 nmol l −1 per degree, p = 0.14) [ 12 ]. Vitamin D deficiency (low serum 25(OH)D) is very common in western dwelling South Asian populations, including very severe deficiency (less than 12.5 nmol l −1 ) in 27–60% of individuals [ 13 ]. Although seasonal variation in vitamin D is found, a study from Birmingham, UK showed that 94% were vitamin D deficient in winter and 82% in summer [ 14 ].…”

Effect of Vitamin D Deficiency on Liver Cancer Risk: A Systematic Review and Meta-Analysis

“…Vitamin D deficiency and insufficiency is a global phenomenon, and it has been estimated that approximately 60% of adults worldwide are vitamin D deficient and insufficient (Daly et al, 2012). It is known that Vitamin D deficiency is particularly prevalent in South Asian, including severe deficiency (<12.5 nmol/l) up to 27-60% of individuals (Darling, 2020). In India, vitamin D deficiency prevails in epidemic proportions, with a prevalence of 70%-100% in the general population (Ritu and Ajay, 2014).…”

Implementation strategies for improving vitamin D status and increasing vitamin D intake in the UK: current controversies and future perspectives: proceedings of the 2nd Rank Prize Funds Forum on vitamin D

“…Regardless of the season when the samples were taken, median serum 25(OH)D concentrations for Indian, Pakistani and Bangladeshi participants were all close to, or below 25 nmol/L, with summer concentrations being only slightly higher than during other seasons (22) . During winter and spring, approximately 60% of participants had a serum Accepted manuscript nmol/L; 20% had 25(OH)D <15 nmol/L.…”

“…Data from the 2010 Health Survey for England has also highlighted that Asian participants (over 16 years) had a lower mean 25(OH)D status (20.5 nmol/L) than White participants (45.8 nmol/L) (20) . Dr Darling presented findings from a secondary analysis of data from the UK Biobank cohort (2006-2010) on the determinants of 25(OH)D status for South Asian adults (Indian, Pakistani and Bangladeshi) living in the UK, including information on serum 25(OH)D concentration as well as vitamin D dietary intakes and supplement use (21,22) . The cohort comprises over 500,000 people, aged 40-69 years old, among whom are 8024 participants of South Asian ethnicity.…”