Brittle hair and cracked lips might be more than the result of the cold, dry winter weather – they could indicate your body’s iron stores are running on empty.

Knowing the signs of low iron, which can become anemia if not addressed, is important – especially if you’re at higher risk, says Stephen Macari, MD, primary care provider with Hartford HealthCare Medical Group in Stamford.

Here’s why you might be iron deficient and the symptoms to watch for (including some surprising ones), according to Dr. Macari.

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Our bodies need iron to help circulate oxygen.

“Iron is one of the most important components of the human body,” he begins. “It has multiple roles but the most critical one is creating hemoglobin to carry oxygen in the blood to tissues.”

The body typically holds some iron in reserve for times when diet doesn’t provide enough, but that can be easily wiped out, Dr. Macari says.

“It can quickly run out in the process of making new red blood cells or any other processes iron is involved in,” he explains.

Why is my iron low?

Iron deficiency occurs when your body lacks enough iron. Your diet is one common reason it can occur.

“Vegans and vegetarians can be prone to deficiency because they take in less iron, even though foods like spinach, broccoli, beans and tofu are high in it,” he says.

Gender is another key factor.

“Women are also more prone since menstruation leaves them with a constant need for new blood cells.”

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12 symptoms of low iron to watch out for

Because iron’s role is to circulate oxygen, when less flows, the first symptoms you may experience include:

  • Fatigue
  • Headache
  • Restless legs

The first three symptoms, Dr. Macari says, are easily overlooked or attributed to other things. He says rarer signs of iron deficiency can be:

  • Cracks at the corner of your mouth.
  • Changes in the tongue.
  • Scooped nails.
  • Feeling cold all the time. Iron is needed for proper functioning of the thyroid, which regulates body temperature.
  • Easily feeling short of breath.
  • Increased anxiety or irritability.
  • Brittle or thinning hair.
  • A condition called pica, when you crave non-food substances like paper, starch, dirt or ice.

“These signs are more obvious when they happen. Something like fatigue can slowly set in and just feel like you’re not sleeping well,” he says.

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How to treat low iron levels

The good news, Dr. Macari stresses, is that your iron supply is relatively easy to track and replenish.

If you’re concerned, speak with your primary care provider who can order a simple blood test.

If you’re low on iron, some simple ways to replenish your supply include:

  • Adding iron-rich foods to your meals. Iron is found in protein, vegetables, fruits and bread products.
  • Taking an over-the-counter supplement.

In some severe cases, people might need intravenous iron infusions, but your provider can advise.