Spurred on by the discussion that the new BibRave Podcast had it got me thinking more about the importance of iron, especially for runners.
So first the disclaimers - I'm not a medical professional, I'm not recommending any specific treatment and you should ALWAYS consult your doctor before starting any medical treatment or change to diet and exercise.
Phew - now that's out of the way. Let's dig in.
So about a year ago I was planning to cruise through summer into the Dumbo Double Dare at Disneyland, but then life happened and I find myself a new member of the BibRavePro team and signing up for my first 50k which was about 3 months away which meant my running was going to be anything but "cruising". Pretty crazy!
In anticipation of taking on a HUGE change in my running volume quickly I started eating better, getting more protein, and incorporating an iron supplement into my diet. I did this on my own and I wouldn't recommend anyone following my lead but I took a moderate dose only a few times a week and had researched ALL the side effects of overdosing. Which made it... okay?
Iron or other metals are not like calcium or B-vitamins where the excess just gets flushed out, they can be very harmful to your health. Do not just start taking a ton of iron!
So about a year ago I started taking iron to offset a heavy training load and in hopes that it would help me with all my elevation training. I had read over and over about how runners were more than likely deficient in iron and all ths signs (most of which I was experiencing).
So why on average are runners so definicent in iron? Let's dive in.
Humans have 4 iron-binding proteins, hemoglobin, ferritin, lactoferrin and transferrin. Hemoglobin is located in red blood cells. Transferrin is found in blood and tissue fluids. Lactoferrin is found in milk, blood, tears and saliva. Ferritin is found in every cell type.
When we are talking iron deficiency we are generally talking about how much hemoglobin the body has and how readily the iron is being absorbed.
When you run your body goes through...
Also called haemolysis or hematolysis, and is the "breakdown or destruction of red blood cells so that the contained oxygen-carrying pigment hemoglobin is freed into the surrounding medium." (Britannica.com). In non-runners this happens naturally in small doses when a cell becomes old and releases it's iron so these cells can be removed from the body, pretty nifty!
It becomes an issue when this process is sped up and causes more hemogloblin (the iron binding protein) to be released into the bloodstream. It is generally recognized that any repetitive trauma (aka running) will also cause this process to quicken.
So let's recap...
Repetitive trauma (aka running) causes hemolysis which releases hemoglobin, the protein responsible for carrying oxygen in the blood. Normally, a large portion of your body's reserve of iron is in your hemoglobin and your body needs to rebuild (using iron) your hemoglobin after hemolysis. By damaging the hemoglobin your body loses iron but anemia is the symptom of low hemoglobin levels.
This is a VAST oversimplification of the issue so sorry science people who study this stuff!
And of course we have a few studies that show what's really happening. Like this small study with 113 joggers and competitive runners. Of the 33 females and 80 males they found higher levels of hemoglobin in their blood plasma., blood is made of 2 main things, your plasma and your redblood cells. This showed that hemolysis occurred at that after a run, hemoglobin was being unbound from the redblood cell.
And according to other studies it doesn't matter if you run fast or slow, if you are running you are causing quickened hemolysis when compared to sedetary individuals.
Okay so now we know all about hemolysis, hemoglobin and iron but what can you do now?
Symptoms of Low Iron Levels
First let's go through the symptoms, which sometimes disguise as over-training:
- Chronic exhaustion
- Increased rate of perceived effort (feel like you are working harder than you normally do)
- Distracted or lack of concentration
Basically without the proper hemoglobin levels (which are directly related to iron levels) you are tired, sluggish and maybe even disoriented because your red blood cells aren't carrying oxygen efficiently. And this is all because your blood cells don't have enough iron to bind to and those carry oxygen around your body.
How to Get Iron Everyday
If you think you might be iron deficient, definitely go get a blood test. It doesn't hurt (well except for the needle) and can give you a definitive answer. You can also test it out by adding some iron rish foods to your diet and see how you feel. These include:
- Meat: Red meat, dark meat poultry and seafood
- Dark leafy greens - spinach and kale are great and mixing them with some vitamin C will increase your absorption!
- Sunflower seeds and nuts
You can check out a more details list here: Top 10 Food Highest in Iron
You can also check out some more information from IRONMAN here: Triathletes Guide to Iron
So hopefully this helps to explain the link between running and iron deficiency. It is VERY common in runners so don't be shy to bring it up to your doctor the next time you visit.
So what questions do you have about iron?
I'd love to continue my research and help you all!
Do have a friend who might be awed by your knowledge of hemolysis?