Table 1 Overview of vitamin D deficiency in regions highly affected by COVID-19.

From: Perspective: improving vitamin D status in the management of COVID-19

CountryPopulation of study25(OH) D statusPrevalence
China [30]364 Chinese men aged 60–75Deficiency: <50 nmol/L
Insufficiency: 50–75 nmol/L
72%
22%
Iran [31]Meta-analysis of 48 studies including 1911 men and 3683 women (excluding pregnant women, children, and patients)Deficiency: <50 nmol/LPooled prevalence
55.21% in men
64.71 in women
Italy and Spain [32]420 patients ≥65 years old admitted to rehabilitation centersDeficiency: <50 nmol/L
Insufficiency: 50–75 nmol/L
94.3%
81.2%
United States [33]26010 adults in the National Health and Nutrition Examination Survey 2001–2010Deficiency: <50 nmol/L
Insufficiency: 50–75 nmol/L
28.9%
41.4%
France [34]297 subjects studied in January and February 2015Deficiency: <50 nmol/L75.1%
United Kingdom [35]278 patients with chronic obstructive pulmonary disease, aged 41–92 years in LondonDeficiency: <50 nmol/L61.5%