How low iron affects the body

Similar to other micronutrients, when iron is not present in the body in sufficient amounts, it can cause certain side effects. Read this article to find out why iron supplementation is worth it for people with iron deficiency.

Plate containing iron-rich foods

Key takeaways:

  • Iron is an important nutrient the body needs for producing hemoglobin, a protein that gives blood its red color and carries oxygen to different cells of the body.
  • Iron deficiency can affect the body by causing symptoms like pale skin, restless leg syndrome, and constant fatigue.
  • Dietary sources of iron include whole grains, leafy vegetables, and legumes. It can also be obtained from iron supplements.

Iron is very important to the body because the body needs it to produce hemoglobin, the protein in red blood cells that carries oxygen and gives blood its red color. Aside from hemoglobin, iron is also found in the cells of the muscle called myoglobin. Myoglobin accepts, stores, and releases oxygen. 

Iron is also a component of some enzymes involved in collagen synthesis and proteins essential for energy metabolism and breathing. 

But when iron is low in the body, it can cause side effects such as depression, paleness, strange cravings, unusual tiredness, and neurological problems like attention deficit hyperactivity disorder (ADHD). Iron-rich foods, such as dark green leafy vegetables, whole-grain bread, tofu, legumes, liver, and iron supplements, can help the body keep its iron stores, which can prevent these side effects.

Here is how low iron affects the body:

1. Pale skin

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Low iron levels can cause pale skin (also called pallor), including the inner part of the lower eyelids.

Because hemoglobin in red blood cells gives blood its reddish color, reduced hemoglobin as a result of iron deficiency will make the color less reddish, which is why the skin looks paler.

You may notice the paleness all over your body or in certain parts like the gums, face, nails, inside the lower eyes, and lips.

Even though the only way to confirm iron deficiency is by running a blood test, the paleness of the skin is often among the initial things healthcare professionals check for when diagnosing iron deficiency.

2. Restless leg syndrome (RLS)

A low iron level in the body has been linked to restless leg syndrome. Restless leg syndrome is a nervous system disorder that causes a strong, uncontrollable urge to move the legs. It is usually due to uncomfortable sensations or itchiness in the legs.

Restless leg syndrome is usually worse at night and can affect a person’s sleep by making it difficult to fall asleep.

Iron-deficiency anemia is one of the secondary causes of restless leg syndrome. According to a 2020 study that investigated the prevalence of non-anemic iron deficiency in people with RLS, people with iron deficiency were 6 times more likely to have RLS than people who were not deficient.

3. Constant unusual tiredness

Iron deficiency can cause a person to be exhausted. It is one of the common side effects of iron deficiency. 

The fatigue that comes with iron deficiency is because there is not enough iron to make the hemoglobin needed to transport oxygen all over the body. This results in less oxygen getting to the muscles and tissues.

When the muscles, tissues, and cells cannot get enough oxygen, they get deprived of energy. The heart gets affected, too, as it has to do extra work to get more oxygen-containing blood transported around the body.

You may associate your constant tiredness with your busy life and stress. However, tiredness combined with irritability and difficulty concentrating is a more significant indicator of iron deficiency.

4. Heart palpitations

Heart palpitation is the feeling of the heart beating fast, racing, and pounding. It also happens when you feel like you skipped a heartbeat. Iron deficiency can cause heart palpitations.

A 2015 study of cardiac events in 166 people with persistent atrial fibrillation suggests that the link between iron deficiency anemia and heart conditions may have something to do with how much oxygen is getting to the heart.

Because the heart has to do extra work to circulate oxygen to all parts of the body when the iron level is low, the heart may start to beat irregularly, or you may start feeling your heart beating unusually fast.

Also, iron deficiency may worsen medical conditions like coronary heart disease and heart failure. 

5. Damaged or brittle hair and skin

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A reduced level of hemoglobin in the blood may reduce the amount of oxygen that is circulating to the hair and skin cells, causing the skin and hair to get dry, weak, and damaged. This is why iron deficiency is also linked with loss of hair mass and strength. 

This shows that the hair can give clues about what is going on in the body. While it is normal to lose small amounts of hair when you comb or wash your hair, losing larger hair clumps may be a sign of iron deficiency. 

6. Brittle fingernails

Like the hair, the nails can also tell some things about the health. One of the effects of iron deficiency is brittle nails or spoon-shaped nails (also called koilonychia). 

Spoon-shaped nails are nails that look like their center is scooped out, causing the nails to be thin and their edges to point upwards. 

Initially, iron deficiency causes the nails to be brittle and crack easily. If not addressed, the brittle nails can further develop into spoon-shaped nails. 

Other symptoms of low iron

Other things that may signal iron deficiency include:

  • Depression
  • Cold hands and feet
  • Poor appetite
  • Frequent infections

Iron deficiency can also cause neurological effects like restless leg syndrome and attention deficit hyperactivity disorder (ADHD) in children.

Wrap up

While the average adult male has about 1,000 mg of stored iron, women, on average, have about 300 mg of stored iron. Eating foods low in iron can cause the depletion of the iron stores in the body, leading to iron deficiency anemia. Iron deficiency anemia is a form of anemia caused by a low amount of healthy red blood cells. It occurs when the body lacks enough iron to make hemoglobin.

When iron is lacking in the body, it affects the body adversely in certain ways. You may not know what is wrong with you until you see a doctor. Telling your doctor the symptoms you are experiencing will help in the diagnosis.

Also, aside from inadequate dietary intake of iron, iron deficiency can be caused by other underlying conditions such as inflammatory bowel disease, celiac disease, and loss of too much blood due to internal bleeding and heavy periods. This is why you must see your doctor once you notice something abnormal about your body.

Frequently Asked Questions (FAQs)

What happens when the iron in the body is low?

When the iron level in the body is low, it can lead to anemia. Anemia occurs when there is insufficient hemoglobin or healthy red blood cells, causing the cells not to work as they should. Common symptoms people with low iron levels experience include pallor, fatigue, and breathlessness.

How does iron deficiency anemia affect the body?

Since impaired red blood cells or insufficient hemoglobin are produced in people with iron-deficiency anemia, they will experience decreased oxygen delivery to different parts of their body. This can cause symptoms like yellowing or paleness of the skin, shortness of breath, brittle nails, headaches, weakness, and extreme fatigue.

What causes iron levels to drop in the body?

Different things can cause the level of iron stores in the body to drop, including pregnancy, chronic blood loss, and not getting enough iron from dietary sources.

Also, certain foods, like those that contain calcium, phytates, and polyphenols, and medications like the ones for reducing stomach acid, can impair iron absorption. Reduced iron absorption over time can deplete iron stores in the body.


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