Iron supplements increase your risk of iron toxicity — here's how to recognize the symptoms and get help

When a person isn't getting enough iron, they may experience symptoms such as excessive fatigue, shortness of breath, and anemia.

Taking iron supplements may help alleviate these problems but can also come with its own potential side effects when iron is taken in high doses and in excess of your needs.

Here's what you need to know about taking iron supplements and how to lower your risk of unpleasant side effects.

Iron supplement side effects   

Iron supplements can contain more than 100% of your daily iron needs, which means it can be easy to exceed your upper limit for iron and experience side effects as a result.

Ingesting too much iron can corrode tissue in the gastrointestinal tract. "Over time, iron can accumulate in the organs, and cause irreversible damage to organs like the liver and brain," says DeMasi.  

Although rare, if you consume too much iron over time it can cause iron toxicity, which can lead to:

• Liver disease
• Brittle bones
• Heart disease 

Visit a doctor immediately if you or children in your care experience any side effects from iron supplements. 

An iron overdose can be deadly for children. Between 1983 and 2000, 43 children died after ingesting high doses of iron. 

"Iron toxicity is extremely dangerous for children and can lead to multi-organ failure or death in severe cases," says DeMasi. "The first signs of toxicity are nausea, vomiting, diarrhea, and stomach pain." 

Iron supplement dosage 

Before taking an iron supplement, speak with a doctor to determine the proper dosage. Overall, the amount of iron a person should take per day depends on their age and gender:

• Children 1 to 3 years: 7 mg
• Children 4 to 8 years: 10 mg 
• Children 9 to 13: 8 mg 
• Adolescent males: 11 mg
• Adolescent females: 15 mg 
• Adult males: 8 mg 
• Adult females: 18 mg 
• Pregnant people: 27 mg

According to DeMasi, people who are at a high-risk of iron overdose, and therefore, should not supplement, include those with:

• Hereditary hemochromatosis 
• Frequent red blood cell transfusions
• Myelodysplastic syndrome
• Thalassemia
• Sickle cell disease

Most other individuals do not need to take iron supplements. "Individuals who have normal iron and hemoglobin levels and are not pregnant and of child-bearing age do not generally need iron supplements," says Bansari Acharya, a registered dietitian-nutritionist. 

Iron supplements are available in many forms, including: 

• Powder
• Chewable tablet 
• Capsule
• Extended-release 
• Liquid
• Syrup

Tips for taking iron supplements

The body does not absorb iron as well if it's coming from supplements. However, there are a few ways you can improve your body's ability to absorb iron. According to DeMasi and Acharya, these include: 

• Eat more vitamin C-rich foods like citrus fruits, strawberries, bell peppers, and broccoli.
• Avoid consuming food or beverages high in calcium, like milk or yogurt when you take supplements, as they can limit iron absorption. 
• Take iron supplements one hour before a meal or two hours after since it's best absorbed on an empty stomach. 

The form of iron supplements you take can also help mitigate side effects. According to DeMasi, some people find liquid iron and slow-release iron cause fewer gastrointestinal side effects, since they are more readily absorbed.

Insider's takeaway

Iron supplements can lead to side effects such as gastrointestinal distress and fainting. If you continue to supplement with much more iron than you need, you may experience iron toxicity, which can lead to brittle bones or liver disease.

Unless you are in a high-risk group or have low iron levels, iron supplementation is usually unnecessary. 

If you are considering taking iron supplements, speak with your doctor first as they can help you determine the correct dosage. 

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