9 signs of iron deficiency everyone should know about : Did you know that iron deficiency is the most common nutritional disorder in the world? According to the World Health Organization, more than 30% of the world’s population suffers from iron deficiency.

Women, infants, children, vegetarians, and frequent blood donors are among the most at risk populations, says Mayo Clinic.It is important to be aware of the signs and symptoms, as iron deficiency can cause heart problems and stunt growth. Here are the signs and symptoms you should know, as explained by Women’s Health:

1. Fatigue. Iron is used to make hemoglobin, the material in red blood cells that carries oxygen to the entire body. When you’re iron deficient, your blood cells take a hit. This can make you feel exhausted.

2. Breathlessness. When your blood cells are deprived of oxygen, easy activities like walking can make you gasp for breath.

3. Sore muscles. When you don’t have enough iron, your muscles are unable to recover properly. If your regular morning jog is causing you more pain than usual, you may be iron deficient.

4. Difficulty focusing. Iron is important for the proper function of neurotransmitters. If you have trouble focusing or feel less functional than usual, you may be suffering from iron deficiency.

5. Apathy. That lapse in proper neurotransmitter function can also make you feel apathetic toward the things that typically bring you joy, including friends and family.

6. Unusually pale skin. A pale complexion may be a sign of reduced blood flow, a byproduct of iron deficiency.

6. Pink or red urine. If your urine turns pink after eating beets, your body may not have the iron necessary to absorb certain pigments.

8. Brittle nails. Concave or spoon-shaped depressions in the nails are signs of iron deficiency, as are frail fingernails and toenails.

9. Frequent infections. If you’ve been sick more often than usual, talk to your doctor about your diet and ask for a blood test. You may be surprised to learn you’re iron deficient.