Measuring your iron levels to make sure you are meeting your needs is key. After all, you can’t monitor what you don’t measure. But even we’ll admit, not all science is easily translated into plain English. That’s exactly what we strive to do here at InsideTracker. And we’ve just made understanding your iron group easier than ever!
Your iron group is comprised of five biomarkers: ferritin, hemoglobin, TS, blood iron, and total iron binding capacity. These five markers measure things like iron storage, the amount of iron your blood can carry, and the amount of oxygen your blood can circulate throughout your body. Tracking your iron group can give you a view into whether you're meeting, exceeding, or falling short of your body's iron needs.
By adding a short interpretation to your iron group, we hope it will help you understand your specific combination of iron markers and how they all work together.
One factor that you may not have expected to affect your iron group is inflammation. So, could it be affecting your iron group? Here’s what you need to know...
Why does inflammation matter?
In 2000, scientists discovered a compound called hepcidin, and deemed it the “Master Regulator” of iron metabolism.1 Essentially, hepcidin controls whether iron can get into and out of cells (via ferroportin, the main channel for iron flux into and out of cells).2 This affects a few key processes related to iron metabolism:- Iron absorption from the digestive tract
- Iron recycling from damaged cells
- Utilization of iron from ferritin stores
Typically, hepcidin levels are increased when there is a high level of circulating iron. This reduces absorption of iron from the diet, reduces the amount of recycled iron released into the system, and converts more iron into the storage form, ferritin. All of this helps to protect the body from iron overload.
Inflammation can also cause hepcidin production to increase.3 The increase in response to inflammation helps our bodies defend against invading pathogens. Foreign invaders, like bacteria and viruses, need iron to survive and thrive just like we do. Therefore, the body responds by increasing hepcidin and removing a lot of iron from circulation so it is not available to “the invaders,” essentially stunting their ability to grow and replicate. The result? A lot of iron being put into storage and converted to ferritin.
Ferritin is usually a good measure of overall iron status, but in the presence of inflammation, it functions as an immune response, not as a marker of iron status.
How to measure inflammation
At InsideTracker, our markers of inflammation are hsCRP and WBC. We measure hsCRP because it is a more stable marker of inflammation than other frequently measured inflammatory markers (like IL-6) and has a substantial amount of research on improvement from lifestyle changes. Like IL-6, hsCRP spikes after strenuous exercise. It typically peaks 24-hours post exercise, and returns to normal around 72-hours.4,5,6,7Elevations in hsCRP that cannot be attributed to strenuous exercise may be caused by a number other issues. For our users, the typical reason is a nagging injury. Other causes can be hormonal birth control, obesity, autoimmune disease, or poor diet and lifestyle.8,9,10
Elevations in white blood cell markers can also signify that your body is battling an infection, and therefore, is mounting an immune response. This usually includes an increase in inflammatory compounds to help fight the invading organism and can lead to similar effects on the iron group.
The white blood cell count is made up of 5 different types of white blood cells and each respond to a different type of threat (bacterial, viral, parasitic, allergy, or chronic inflammation). Read more about white blood cells tested in the complete blood count, or CBC (part of our Ultimate plan) here.
How to interpret your iron group
If your inflammation levels are high and your ferritin is in the optimal zone, look at your total iron binding capacity, or TIBC, level. TIBC is similar to transferrin, a major iron transporting protein. High levels of TIBC and transferrin indicate high levels of iron binding capacity – in other words, your body has a lot of feelers out for iron to absorb and you should increase your intake of iron.3,11 Normal ferritin levels with normal TIBC levels is a good indication that you are likely meeting your iron needs, regardless of inflammation.
Normal ferritin with high levels of TIBC can indicate that you aren’t getting enough iron.
In fact, for female InsideTracker users with optimal levels of ferritin, the average TIBC level was significantly higher for those with hsCRP levels greater than 1 mg/L compared to females with hsCRP below 1 mg/L (p<0.001).
Another interesting scenario is a sharp drop in serum iron and TS with subsequent increases in WBC or hsCRP.
Since a spike in hepcidin caused by inflammation or infection causes iron to be removed from circulation, these are expected fluctuations and will likely resolve themselves after the inflammation has subsided.3
So, do you know what your iron and inflammation levels are? InsideTracker can help you interpret your values and develop a personalized plan for getting them into your optimal range. Stay tuned for an upcoming blog on the best way to improve low ferritin levels.
Ashley Reaver, MS, RD, CSSD
Ashley is the Lead Nutrition Scientist at InsideTracker. As a registered dietitian and educator, Ashley enjoys cooking and teaching individuals the power that food has on their health. You’ll find Ashley hiking, eating, and spending time with her family. Follow her on Instagram @lower.cholesterol.nutrition.
References:
[1] Park, Christina H., et al. "Hepcidin, a urinary antimicrobial peptide synthesized in the liver." Journal of biological chemistry 276.11 (2001): 7806-7810.[2] Crielaard, Bart J., Twan Lammers, and Stefano Rivella. "Targeting iron metabolism in drug discovery and delivery." Nature Reviews Drug Discovery(2017).
[3] Ganz, Tomas, and Elizabeta Nemeth. "Iron sequestration and anemia of inflammation." Seminars in hematology. Vol. 46. No. 4. WB Saunders, 2009.
[4] Langberg, Henning, et al. "Substantial elevation of interleukin‐6 concentration in peritendinous tissue, in contrast to muscle, following prolonged exercise in humans." The Journal of physiology 542.3 (2002): 985-990.
[5] Ispirlidis, Ioannis, et al. "Time-course of changes in inflammatory and performance responses following a soccer game." Clinical Journal of Sport Medicine 18.5 (2008): 423-431.
[6] Pedersen, Bente Klarlund, et al. "The cytokine response to strenuous exercise." Canadian journal of physiology and pharmacology 76.5 (1998): 505-511.
[7] Sim, Marc, et al. "Iron regulation in athletes: exploring the menstrual cycle and effects of different exercise modalities on hepcidin production." International journal of sport nutrition and exercise metabolism 24.2 (2014): 177-187.
[8] Bahceci, M., et al. "The correlation between adiposity and adiponectin, tumor necrosis factor α, interleukin-6 and high sensitivity C-reactive protein levels. Is adipocyte size associated with inflammation in adults?" Journal of endocrinological investigation 30.3 (2007): 210-214.
[9] Sørensen, Cecilie J., et al. "Combined oral contraception and obesity are strong predictors of low-grade inflammation in healthy individuals: results from the Danish Blood Donor Study (DBDS)." PloS one 9.2 (2014): e88196.
[10] Fedewa, Michael V., Elizabeth D. Hathaway, and Christie L. Ward-Ritacco. "Effect of exercise training on C reactive protein: a systematic review and meta-analysis of randomised and non-randomised controlled trials." British Journal of Sports Medicine (2016): bjsports-2016.
[11] Skikne, Barry S., Carol H. Flowers, and J. D. Cook. "Serum transferrin receptor: a quantitative measure of tissue iron deficiency." Blood 75.9 (1990): 1870-1876.