Sandra is a 72 year old retired manager who presents with tiredness and is requesting routine bloods to be carried out. There are no red flag symptoms of weight loss, anorexia or malaise. Her Type 2 Diabetes, Gout and her non-ulcer dyspepsia symptoms are all well controlled with appropriate medication. Her results are unremarkable except her serum B12 level is low. Her folate levels are normal along with her Haemoglobin and MCV (Mean cell volume).
Which one of the following would not cause a low B12 level?