Iron deficiency is a common and widespread problem. Unless a major hemorrhage has occurred, iron deficiency normally develops over a long period of time. Depending on factors such as treatment method, diet, and how easily a person absorbs iron, it could also take some time for iron levels to return to and be maintained at a normal level.

Although the terms are often used synonymously, iron deficiency and anemia aren't exactly the same thing. Anemia results from insufficient red blood cells (and therefore hemoglobin, which gives the cells their red color). It's possible to have an iron deficiency without having anemia because hemoglobin levels are still normal. Similarly, you can also have anemia without an iron deficiency. This is because anemia can be caused by other things (such as blood loss).

However, iron deficiency anemia is common, perhaps because your body needs iron to make hemoglobin. In the case of iron deficiency anemia, both iron levels and hemoglobin are low.

In the developed world, iron deficiency can be easily identified and treated. Even so, it remains the most common anemia and nutrition disorder worldwide. Symptoms of iron deficiency are very similar to low hemoglobin. A blood test can determine whether the problem is coming from low iron, hemoglobin, both low iron and hemoglobin, or something else.

The following are some of the potential signs and symptoms of iron deficiency to watch out for.

Feelings of fatigue

Fatigue is a symptom that could be attributed to any number of health problems. It is also one of many possible consequences of a busy modern lifestyle, so experiencing fatigue will likely not lead you to think of iron deficiency as a possibility right away.

Fatigue is one of the most common symptoms of iron deficiency. The primary reason for this may be due to the low hemoglobin levels that often go hand in hand with iron deficiency. With insufficient red blood cells to pump oxygen around the body effectively, a person who is low in iron can easily be left feeling tired.

Improvements in iron levels of the body in people with iron deficiency have been shown to improve fatigue status.

Muscle weakness

Similarly, if there is not enough oxygen to be pumped out to working muscles, the muscles can end up feeling weaker. This can make relatively gentle exercise feel more strenuous than it would if hemoglobin levels were normal.

Iron supplementation in iron-deficient athletes has been shown to significantly improve endurance levels and overall physical performance.

Poor concentration and low productivity

Iron deficiency can impair cognitive performance, decrease work capacity, and reduce productivity levels. The World Health Organization highlights this effect in several different populations.

For example, work capacity in agricultural workers increased quickly when iron supplementation was administered. Anemic female workers in China were found to be 15% less efficient in performing their work.

Pale skin

Pale skin is another common sign of iron deficiency. Again, this is related to low levels of hemoglobin, since this is what gives blood its red color. Pale skin could present itself in one particular area or in several areas of the body. Commonly, these include the face, nails, and lower eyelids.

Cravings for substances that do not provide nutritional value

Pica is the term given to the desire to eat (often non-food) substances that do not offer nutritional value to the body and could also be harmful. Examples include dirt, chalk, and ice.

The prevalence of pica is often higher in certain populations such as pregnant women. Micronutrient deficiencies such as low iron are one possible cause of pica. Pica is a less-common but still a possible symptom of iron deficiency.

Cardiovascular problems

When iron deficiency comes with low hemoglobin levels, this also means that circulating oxygen in the body is low. We've already highlighted that the muscles in the body need plenty of oxygen to function effectively, or they will end up in a weakened state.

It's even more widely known that our lungs need plenty of oxygen. Low hemoglobin levels and subsequently oxygen can result in a person feeling short of breath, another symptom of iron deficiency

It's also possible that severe iron deficiency could cause heart problems, including chest pain or heart palpitations. This may be because the heart is being forced to work harder. Iron deficiency has been identified as a common problem in patients with chronic heart failure.

Headaches or dizziness

People who are iron deficient may experience frequent headaches. They may also feel dizzy or lightheaded. Just as the heart, lungs, and muscles of the body require sufficient levels of oxygen, so does the brain.

Further studies are needed to understand the link between iron deficiency and problems with headaches or dizziness. Low hemoglobin levels and consequently low oxygen could be a contributing factor.

Restless legs

Restless legs syndrome is characterized by unintended movements in the lower body. It often occurs in the evening or during the night when a person is sitting or lying still.

There are several possible causes of restless legs, and often the cause may be unknown. Iron deficiency is one possible underlying problem to explore.

Poor nail health

Brittle nails or spooning of the nails are possible signs of iron deficiency. Brittle nails could offer one early warning sign to get your iron levels checked. Spoon-shaped nails may occur in more advanced cases of iron deficiency.

Mouth and tongue problems

Common signs of iron deficiency can often be seen around and inside the mouth. A person with iron-deficiency may have cracked red skin or sores on the sides of the mouth.

The tongue may also feel sore, or become swollen. Patients with iron-deficient anemia have been found to have significantly higher levels of oral manifestations as compared to a control group. These included a dry mouth, and burning sensations, among others.

In conclusion

There are several potential signs and symptoms of iron deficiency. Some, such as fatigue, are more common, and may be signs of a variety of other issues. Other symptoms are a bit more specific, and could be the first warning sign to get your iron levels checked.

It is likely that more than one sign or symptom will be present. A blood test can identify an iron deficiency so that an appropriate treatment plan can be implemented effectively.