Iron supplementation- Why less is better

About a year ago, I wrote a blog on “why you should get your ferritin levels checked.” (click here for more info). As outlined in this blog, low ferritin levels, which indicate an iron deficiency, are common in athletes and can be detrimental to performance.

My interest in this topic came about after blood testing showing my own ferritin levels were low. Athletes should aim for a ferritin level >30 mcg/L, and mine was 8 mcg/L. I looked back on my blood work from 3 years prior and I have never had a ferritin over 22 mcg/L. I implemented many dietary strategies that were highlighted in that blog to increase the ferritin levels. This past February 2019, I had my ferritin levels retested. The results: a ferritin of 42 mcg/L. My interventions had worked!

During this period, I started taking a daily iron supplement as it’s very difficult to increase your iron levels through food alone. As mentioned, taking an iron supplement without low ferritin levels can be dangerous, so it should only be taken after blood work has confirmed an iron deficiency. I went on to discuss ways to increase the absorption of iron supplements, including:

  • Taking with a vitamin C supplement
  • Taking on an empty stomach
  • Taking away from exercise

However, there was something that I missed in this recommendation, which is supplementation protocol. As mentioned, I took my iron supplement daily as I thought that this was the recommendation. While traditionally this was the recommendation, new research suggests that lower doses taken less frequently may actually be better for correcting deficiencies. This study found that taking lower doses every other day resulted in better absorption. This is because higher or more frequent iron doses may raise levels of hepcidin that consequently decrease absorption. Exercise also increases hepcidin levels, which is why it’s recommended to take iron supplements away from exercise.

As seems to be a common nutrition theme, more is not always better. If you are iron deficient, try taking your iron supplement every other day as a way to better increase absorption.

2019-06-03T17:38:00+00:00 June 4th, 2019|

About the Author:

Learn to fuel your health and performance with Megan Kuikman, Registered Dietitian. Megan provides professional nutrition advice that you can trust. To work with Megan, call: 519-802-9445 or e-mail megankuikmanRD@gmail.com.