Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Iron-Deficiency Anemia ?
    ### Response:
    Not having enough iron in your body causes iron-deficiency anemia. Lack of iron usually is due to blood loss, poor diet, or an inability to absorb enough iron from food.
                
Blood Loss
                
When you lose blood, you lose iron. If you don't have enough iron stored in your body to make up for the lost iron, you'll develop iron-deficiency anemia.
    