<unk>  is common and occurs worldwide. In the US and UK, around 6 percent of the general population have the deficiency; in those over the age of sixty, around 20 percent are deficient. In under-developed countries, the rates are even higher: across Latin America 40 percent are deficient; in some parts of Africa, 70 percent; and in some parts of India, 70 to 80 percent. According to the World Health Organization (WHO),<unk>  may be considered a global public health problem affecting millions of individuals. However, the incidence and prevalence of<unk>  worldwide is unknown due to the limited population-based data available (see table below). Developed countries such as the United States, Germany and the United Kingdom have relatively constant mean vitamin<unk>  concentrations. The data from the National Health and Nutrition Examination Survey (NHANES) reported the prevalence of serum vitamin<unk>  concentrations in the United States population between 1999 to 2002. Serum vitamin<unk>  concentrations of 20% of elderly individuals showed evidence of marginal vitamin<unk>  depletion (serum vitamin<unk> : 148–221 pmol/L). In the United Kingdom, a National Diet and Nutrition Survey (NDNS) was conducted in adults aged between 19 to 64 years in 2000–2001 and in elderly individuals (≥ 65 years) in 1994–95. Six percent of men (n = 632) and 10% of women (n = 667) had low serum vitamin<unk>  concentrations, defined as 65 years) in New Zealand (12%). Currently, there are no nationally representative surveys for any African or South Asian countries. However, the very few surveys which have investigated<unk>  in these countries have been based on local or district level data. These surveys have reported a high prevalence of<unk>  (< 150 pmol/L), among 36% of breastfed and 9% of non-breastfed children (n = 2482) in New Delhi and 47% of adults (n = 204) in Pune, Maharashtra, India. Furthermore, in Kenya a local district survey in Embu (n = 512) revealed that 40% of school-aged children in Kenya had<unk> . Table showing worldwide prevalence of<unk>  (serum/plasma<unk>  < 148 or 150 pmol/L) Group Number of studies Number of participants<unk>  (%) Children (< 1y – 18 years) 14 22,331 12.5 Pregnant women 11 11,381 27.5 Non-pregnant women 16 18,520 16 All adults (Under 60 years) 18 81.438 6 Elderly (60+ years) 25 30,449 19 Derived from Table 2 available on
Vitamin B12 deficiency
Vitamin A deficiency
Copper deficiency
Biotin deficiency
Megavitamin-B6 syndrome
Vitamin E deficiency
Fluorine deficiency
Zinc deficiency