A lack of folate and vitamin B-12 can cause red blood cells to become too large so they can't carry oxygen well.
Disease
Wheat allergy
Learn about the causes, symptoms and treatment of wheat allergy and how they differ from those of celiac disease. Managing either condition means avoiding wheat.
Disease
X-linked agammaglobulinemia
This genetic disease weakens the immune system, mainly in males, and leads to having infections often.