As a runner, should my multivitamin contain iron?

I had an economics professor in college whose favorite answer to questions was, “It depends.” Well, for the question of whether your multivitamin should contain iron, “It depends.”

Not all runners are deficient in iron; if they are, they are not always deficient, depending on factors that can change daily, monthly, and yearly.

Iron is an essential mineral in the body for runners. Iron is vital for creating red blood cells that carry oxygen and nutrients throughout the body. Red blood cells keep blood flowing, increasing the ability of your muscles to recover.

Iron deficiency in runners is natural and a result of running. Runners lose iron from sweating and the breakdown of red blood cells from running, notably each time feet strike the ground. Low iron levels often coincide with an increase in training volume. Additionally, pre-menopausal women lose iron during their periods as blood is rich in iron.

Your multivitamin does not need iron for most runners. If you have a history of low iron levels documented by blood work, you should consider a multivitamin with iron. Instead, for most runners, a plan to counter low iron “moments” is sensible, whether from diet or supplementation. Often, runners will proactively eat a steak or red meat when they sense fatigue as a symptom of low iron. Vegetarian runners will opt for high volumes of dark-leaf vegetables (e.g., kale, spinach), beans, and nuts. Many cereal brands in the U.S. fortify with iron. Additionally, you can consider an iron supplement for these moments.