By the way, doctor. I feel tired, and my joints ache. I've been told I have a vitamin B12 deficiency. What is this--and what causes it?
D018771:Arthralgia / Q000209:etiology*; D005260:Female; D006801:Humans; D018673:Nutrition Policy; D014806:Vitamin B 12 Deficiency / Q000150:complications* / Q000628:therapy