A High Prevalence of Biochemical Evidence of Vitamin B₁₂ or Folate Deficiency does not Translate into a Comparable Prevalence of Anemia

Abstract

Abstract

Characteristics of Anemia in Elderly: A Hospital Based Study in South India

“…48% of all the cases in our study were anemia of chronic disease with renal insufficiency (45.8%) being the most common underlying cause in anemia of chronic disease which is consistent with various epidemiological studies [13,14].…”

Safety and benefits of interventions to increase folate status in malaria‐endemic areas

“…There are additional reasons why survey reports of folate deficiency or folate deficiency anaemia should be interpreted with caution: (i) measurements of folate concentrations in erythrocytes, serum or plasma are subject to large inter‐laboratory and inter‐assay variability (WHO, 2015a); (ii) even though circulating folate concentrations seem unaffected by inflammation (Galloway et al , 2000), they can be increased by Plasmodium infection independently of host folate status; (iii) interventions that raise folate concentrations in erythrocytes or serum do not necessarily improve haemoglobin concentrations or reduce the risk of anaemia (see below), and; (iv) anaemia in the presence of folate deficiency is not necessarily caused by folate deficiency but can also be due to infections or other micronutrient deficiencies (Metz, 2008). Thus, at the population level, folate deficiency can be demonstrated convincingly only through randomised, placebo‐controlled trials showing that folic acid results in improvements in haemoglobin concentrations or functional health outcomes.…”

Haematological implications of folate food fortification

“…There are large populations in the world subsisting on various combinations of vegetarian diets, with low B 12 contents, among whom the resultant higher prevalence of lower serum B 12 concentrations does not translate into an increased prevalence of anaemia. [12] As significant B 12 deficiency is usually due to malabsorption, physiological doses of B 12 added to food would be of questionable value in that they would not be absorbed.…”

“…RCF is not entirely specific for folate deficiency, as it may fall also in primary vitamin B 12 deficiency, despite adequate folate stores. Optimal assessment of folate status after FFF should still include both SF and RCF and also serum B 12 . The extensive assessment of folate nutritional status in populations in the USA as part of NHANES is carried out by measurement of both SF and RCF, and has not changed following the introduction of FFF.…”

“…In assessing folate nutrition, the value of serum folate has been compromised by FFF, and both serum and red cell folate are necessary for optimal assessment of folate status. Although the limited data available suggest that large-scale masking of vitamin B 12 deficiency by FFF has not occurred, it has been suggested that B 12 be incorporated into folate-fortified foods. However, significant B 12 deficiency is usually due to malabsorption, and physiological doses added to food would be of questionable value because they would not be absorbed.…”