Crispy nails
Brittle nails are a less common symptom of iron deficiency, appearing in the later stages of anemia. This condition is called koilonychia. Koilonychia is a nail disease in which the nails become abnormally thin and lose their convexity, becoming flat or even concave. In the early stages, nails can be brittle and break easily. This condition begins to appear in the middle of the nail when the nail is lowered and the edges are raised for a rounded spoon-like appearance.

Swollen, sore tongue and mouth
The parts of our mouth can tell us a lot about our health. Iron deficiency is one of them. For example, if the tongue is swollen, inflamed, or discolored, this is a sign of iron deficiency. In our bodies there is a protein called myoglobin, which binds iron and oxygen found in the muscle tissue of the tongue. Lower myoglobin levels can cause the tongue to become painful, slippery, and swollen. Iron deficiency also leads to dry mouth and the appearance of red cracks and sores at the corners of the mouth.

Shortness of breath or chest pain
Shortness of breath or chest pain, especially with exercise, is another symptom of iron deficiency. Because hemoglobin is limited in red blood cells, the amount of oxygen transported throughout the rest of the body is limited. So, our body has to try to compensate and produce more oxygen for the organs to function properly, leading to shortness of breath or chest tightness.

Dizziness and headache
Iron deficiency can also cause headaches or migraines. This is because not enough oxygen reaches the brain, causing blood vessels to bulge, causing pressure leading to headaches or migraines.
In addition, people with iron deficiency will be prone to dizziness and lightheadedness. When hemoglobin levels drop or remain low, the body will need oxygen, causing symptoms of lightheadedness and dizziness. Dizziness is caused by a lack of oxygen in the brain or low blood pressure due to poor oxygen supply from the heart and blood vessels.

Pale skin
Hemoglobin in red blood cells is what gives us healthy, rosy skin. With iron deficiency, the human body cannot produce enough hemoglobin to red blood cells, resulting in paler skin. Regardless of your skin tone, if your lips, gums, fingernails, and the inside of your lower eyelids are lighter than usual, it could be a sign of iron deficiency.

Legs often shrink
Low levels of iron in the blood can lead to a decrease in dopamine, a brain chemical that is important for movement and can cause contracture leg syndrome. Dopamine acts as a messenger between the brain and the nervous system that helps the brain regulate and coordinate movement.
If nerve cells are damaged, the amount of dopamine in the brain is reduced, causing muscle spasms and involuntary movements. Dopamine levels naturally drop at the end of the day, which may explain why the symptoms of contracture leg syndrome often appear in the evening and at night.

Abdominal pain and bloody urine
Intravascular hemolysis, a condition caused by iron deficiency, is where red blood cells break down in the blood stream and they release iron that is then dissolved in the urine. This sometimes happens in people who exercise with intensity, especially jogging, and it can cause injury to the small blood vessels in the feet, known as “circulatory hematuria”.
Sources: Brightside

Unusual fatigue
Fatigue is a very common symptom of iron deficiency. This is because our body lacks iron to produce a protein called hemoglobin in red blood cells that is responsible for transporting oxygen from the lungs to other parts of the body. When the body lacks hemoglobin, the muscles and tissues receive less oxygen, leading to fatigue. Fatigue is very common in today’s life. So sometimes it can be difficult to distinguish normal fatigue from symptoms of iron deficiency.
People with iron deficiency often experience the following symptoms:
- Weakness.
- Low energy level.
- Difficulty concentrating.
- Less productivity.

Damaged hair and skin
Hair and skin are considered extra organs outside the body. This is because our bodies prioritize the distribution of oxygen to the most important organs inside the body. When the skin and hair lack iron, they become dry and thinner. A lack of a protein called ferritin is what causes these problems because the protein is needed for the storage and release of iron to all parts of the body over time. Low iron stores increase the incidence of hair loss, especially in postmenopausal women.

Heart beat fast
Irregular heartbeat, or heart palpitations, is another symptom of iron deficiency. This is because low hemoglobin levels cause the heart to work harder to transport oxygen to the organs in the body. This can lead to an irregular heartbeat or a feeling that the heart beats faster. Severe cases can lead to heart failure. These symptoms often appear late, and people with iron deficiency suffer from various symptoms before the tachycardia.
