IMPORTANCE Proton pump inhibitors (PPIs) and histamine 2 receptor antagonists (H2RAs) suppress the production of gastric acid and thus may lead to malabsorption of vitamin B12. However, few data exist regarding the associations between long-term exposure to these medications and vitamin B12 deficiency in large population-based studies. OBJECTIVE To study the association between use of PPIs an...

AIM Metformin is the most widely used oral hypoglycaemic drug, but it may lower B12 status, which could have important clinical implications. We undertook a systematic review and meta-analysis of the relationship between metformin use and vitamin B12 deficiency in persons with type 2 diabetes. METHODS Electronic database searches were undertaken (1st January 1957-1st July 2013) using the Coch...

To the Editor: In the December 11, 2007, issue of PNAS, Selhub et al. (1) suggest that the association between elevated serum folate and methylmalonic acid (MMA) concentrations in vitamin B12 deficiency resulted from disruption of MMA metabolism by folate. An alternative explanation is that the increase in both serum folate and MMA concentrations resulted from the severity of the vitamin B12 de...

OBJECTIVE Vitamin B12 deficiency is associated with many adverse health outcomes and is highly prevalent worldwide. The present study assesses the prevalence of vitamin B12 deficiency and marginal deficiency in Colombian children and women and examines the sociodemographic correlates of serum vitamin B12 concentrations in these groups. DESIGN Cross-sectional, nationally representative survey....

Aim: Deficiency of cobalamin and folate during pregnancy is associated with megaloblastic anemia. Lower levels of folate and vitamin B12 were reported in mothers whose offspring had neural tube defects compared to unaffected controls. Increased methylmalonic acid (MMA) levels are a sensitive indicator of mild vitamin B12 deficiency and elevated homocysteine levels denote vitamin B12 or folate d...

Objective: To find out the prevalence of hyperhomocysteinemia, and deficiencies of folate, vitamin B6 and vitamin B12 in an urban population in Karachi, Pakistan. Methodology: In a pre and post experimental study, eight hundred and seventy-two apparently healthy adults (aged 18-60 years; 355 males and 517 females) were recruited from a low-income urban locality in East of Karachi from February ...

The aim of this study was to examine the association of homozygosity for the methylenetetrahydrofolate reductase (MTHFR) C677T mutation and vitamin B12 deficiency in 360 asymptomatic individuals and to investigate forearm endothelial function in C677T homozygotes. MTHFR C677T mutation and levels of vitamin B12, folic acid, and homocysteine were measured in study participants. Frequency of homoz...

An impaired awareness of hypoglycemia is a serious problem in diabetic patients, which can lead to life-threatening severe hypoglycemia. Recurrent hypoglycemia attenuates the function of the central, mainly hypothalamic, nervous system and it causes an impaired awareness of hypoglycemia. Vitamin B12 deficiency is also associated with the dysfunction of central nervous system. We report a 72-yea...

Vitamin B12 deficiency causes haematological, gastrointestinal, psychiatric and neurological diseases. Subacute combined degeneration (SCD) of the spinal cord, characterised by degeneration of the lateral and posterior columns, is often found due to vitamin B12 deficiency. We report SCD occurring in a 57-year-old man who presented with a 2.5-month history of gradually progressing tingling in th...

Vitamin B12 deficiency results in neuropsychiatric, hematologic, gynecologic, cardiovascular, and cutaneous manifestations. It is seen most commonly in the elderly, malabsorption diseases  (>60% of all cases), vegans, and vegetarians. Manifestations of pernicious anemia may be similar to Addison disease and may lead to a misdiagnosis. Herein, we report two cases of vitamin B12 deficiency in whi...