What Is a Man's Daily Requirement in Grams of Iron Intake?

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Your body requires a sufficient, daily supply of iron to keep it running in top form. Iron helps transport oxygen throughout your body and helps support your immune system. If you have questions about how much iron you need to take each day, consult your medical provider for additional guidance.

Daily Requirement

Adult men require 8 milligrams of iron daily -- which is equivalent to 0.008 grams. Men should not take more than 45 milligrams, or 0.045 grams, of iron daily to limit their risks of developing iron toxicity.


You can get the recommended daily requirement of iron from consuming iron-rich foods, such as fortified cereals, oysters, beef, turkey, oatmeal, beans and lentils, tofu and spinach. If you aren't able to get enough iron from your diet, your physician may recommend treatment with an iron supplement. Iron supplements are normally administered orally; however, if you have a severe iron deficiency, your doctor may recommend iron supplementation via intravenous or IV infusion.

Supplement Side Effects

The bad news is that adding iron supplements to your daily diet may result in unpleasant side effects. Constipation, or infrequent bowel movements, is the most common side effect of iron supplements. You may also experience nausea, heartburn, stomach pain or diarrhea. Intravenous iron treatment may also cause flu-like symptoms, including hives, headache, joint pain and enlarged lymph nodes. Taking up to 45 milligrams of iron per day is safe, according to the FDA. Seek prompt care from your medical provider if you develop a fever, begin vomiting or notice blood in your stools. Severe iron overdose occurs when amounts of iron 50 to 100 times greater than the recommended dietary dose are taken. This kind of iron toxicity can destroy cells in the gastrointestinal tract, resulting in vomiting, bloody diarrhea and even death, notes the University of Maryland Medical Center website.

Medication Interactions

Discuss all medications you are currently taking with your medical provider before you begin treatment with iron supplements. Increasing iron intake may reduce your body's ability to absorb certain medications such as ACE inhibitors, quinolones, bisphosphonates and tetracyclines. Iron supplementation may also decrease the efficacy of levothyroxine, carbidopa and levodopa, the University of Maryland Medical Center website reports. If you have low iron levels, taking antacids, cholestyramine, colestipol or ulcer or heartburn medications in conjunction with iron supplements may decrease the amount of iron your body can absorb.