When standing in front of a mirror, pull your lower eyelid down. If the color is pink, everything is okay. However, if you have anemia, the color may be a pale pink or even yellowish. Anemia is caused by a lack of hemoglobin and indicates that the muscles and tissues in the body aren’t receiving enough oxygen and can’t work at 100%. If you notice that you are pale, you get tired quickly, or breathe heavily, you should get a doctor to examine you.