Iron for runners: Everything you need to know

Group of people running
Group of people running

Nothing kills a runner’s high like low iron. If you’re one of the 56% of joggers and endurance runners who have an iron deficiency, you’ll know what we mean. 

Low iron impacts not only your performance as a runner, but your overall health and wellbeing. Female runners are especially at risk for iron deficiency because of menstruation. 

So, how can you keep iron levels high while keeping your race time low? Here’s everything runners need to know about iron.  

Why do runners need iron? 

Think of iron as your personal oxygen tank. Iron produces a protein called hemoglobin, which helps your red blood cells carry oxygen to your muscles and tissues. It also helps you metabolize carbohydrates — your muscles’ main energy source. 

An iron deficiency doesn’t just rob your body of oxygen. It also impacts the strength, power, and stamina of your muscles — especially during high-intensity exercise, like endurance running. That’s why most runners with low iron will notice a significant dip in their performance levels. 

Can running cause iron deficiency?

You bet. Iron deficiency can impact up to 17% of male runners and 50% of female runners. There are a few reasons why. 

Higher hepcidin 

Exercise can often cause natural inflammation in the body, which releases a hormone called hepcidin. This hormone is like an iron blocker. Even if you’re eating one ribeye steak a day, running can trigger the release of excess hepcidin — making it harder for all that dietary iron to be absorbed into your body. 


Iron, along with other vitamins and minerals, can seep out in your sweat. For endurance athletes in hotter climates, this might be a big contributor to lower-than-normal iron levels.

Foot strike hemolysis 

Did you know you can lose iron by your feet hitting the ground? It’s called foot strike hemolysis, and yes — it’s real. 

As your feet hit the ground during a run, it’s possible for red blood cells to get damaged, causing hemoglobin levels in the body to drop. If you’re a high-mileage runner, foot strike hemolysis might be stealing more iron than you’re able to bring in.  

Everyday iron loss 

Iron can also be lost through urine, the gastro-intestinal (GI) tract, and menstruation — whether you’re a runner or not. 

Symptoms of iron deficiency in runners.

One of the first signs of low iron in runners is fatigue. Struggling to keep your normal pace or feeling exhausted during and after runs are red flags for iron deficiency. 

Other common symptoms include shortness of breath, headaches, dizziness, and an increased or irregular heart rate. For a breakdown of the top 15 signs of an iron deficiency, click here.

Noticing some of these symptoms already? It’s always a good idea to talk to your doctor about testing for an iron deficiency. The simple blood test will give you and your physician a gauge for where your iron levels are at and what you should be working towards moving forward.

What is runner’s anemia?

Iron deficiency and anemia are similar but unique conditions. 

In both cases, your ferritin levels — AKA how well iron is being stored in your body — are low. But if you’re anemic, that means your hemoglobin levels are also very low. That’s a warning sign that it’s time to take your iron seriously. 

Runner’s anemia can severely impact your performance. More than that, it can take the enjoyment out of your run and hurt your overall health. 

Should I stop running if my iron is low?

If you think you might have an iron deficiency, your doctor is the best person to answer that Q. 

Every runner is unique and so their treatment plan will be too. Your doctor might recommend a break from running or a change in frequency or distance. Ultimately, there are several things you can do to boost iron absorption while staying in the running game. 

What can runners to do increase iron absorption?


Step one: eat! Include more iron-rich foods in your diet, such as: 

  • Meat (especially chicken, beef, and lamb) 
  • Seafood (especially shrimp, oysters, and clams) 
  • Beans and legumes 
  • Nuts and seeds
  • Dark molasses
  • Leafy green vegetables 
  • Iron-fortified cereals, grains, and bread

Eating more of these foods every day is a great start, but your body isn’t the best at absorbing dietary iron. Here are a few things you can do to help boost absorption during meals. 

Avoid coffee, milk, or tea while eating iron-rich foods. These beverages are full of calcium, which can suppress iron absorption. Instead, spring for extra Vitamin C during mealtime. A glass of OJ, an orange, or even a Vitamin C supplement can increase absorption and help your body make the most of all the iron you’re eating. 

Meal timing 

When you eat iron can actually make a big difference in how much of it gets absorbed. A recent study found that the best time for iron absorption is in the morning — right after a run. 

Runners who consumed iron within the first half-hour after a 90-minute morning run absorbed 40% more iron than they did for an afternoon run. That’s because hepcidin levels are highest in the afternoon, so a post-noon run can actually inhibit iron absorption. 

Long story short: try eating your most iron-rich meal after your morning exercise routine. Over time, you should start to feel a little more pep in your pace. 

Choose the right iron supplement 

Iron supplements are an easy and effective way to get high levels of iron into your body. 

The only problem? Up to 70% of runners who take oral iron experience some sort of GI side effect. Constipation, bloating, gas — you name it, most iron supplements can cause it. 

When a supplement isn’t formulated the right way, the iron can get broken down by acid along the GI tract. Instead of absorbing into your system, the iron exits your body and causes trouble along the way. That’s why the best iron supplement for runners is one that is specially formulated to increase absorption while curbing those nasty side effects. 

The best iron supplement for runners.

Ferosom Forte is microencapsulated in Liposomal form and protected by a proprietary LCE Coat™. This means it doesn’t have to be converted for your body to absorb it. Best of all, the protective coating keeps the iron safe from acid breakdown so it can go directly to your intestine and absorb into your lymphatic stream — with minimal side effects. 

The bioavailability of Ferosom’s liposomal iron is 3.5 times greater than the free pyrophosphate iron, 2.7 times higher than iron sulfate, and 4.1 times higher compared with iron gluconate.

In other words, this doctor-recommended supplement is perfect for runners who want to solve or prevent an iron deficiency. Plus, it’s infused with Folic acid and Vitamins D, B6, B12, and C for all the nutrients your body could need (and extra iron absorption, of course). 

Would you rather take your iron in capsule or sachet form? Ferosom has both. Click here to try the only Liposomal iron supplement in Canada and keep your stride safe from iron deficiency.