Iron deficiency is one of the most prevalent deficiencies in athletes. Sometimes the diet seems extremely well aligned with regard to the intake of iron-rich foods, however, it seems that in many cases, the problem lies in its absorption. But how can we manipulate these variables?
First, let's understand what hepcidin is.
Hepcidin is the hormone responsible for regulating iron absorption. When it is high, it acts as a "blocker" of ferroportin, leading to a simple conclusion: more hepcidin = less iron absorption.
But at what times is hepcidin elevated?
- At night.
- After exercise (because the human body is in an inflammatory response, producing IL-6 which in turn signals the liver to produce more hepcidin).
This combination, combined with the greater destruction of red blood cells by athletes, means that iron deficiency is a common concern for them.
In a 2009 study, Peeling P et al. made a discovery: up to 30 minutes after exercise, hepcidin levels appear to be lower than pre-exercise.
In addition to this study, McCormick R et al. confirmed the theoretical hypothesis: if a meal was ingested within 30 minutes after exercise, the fraction of iron absorbed was considerably higher compared to not exercising or to an evening meal. After this "window", due to the increase in hepcidin in response to IL-6, iron absorption will decrease.
Rui Lopes
BMS Nutritionists
Peeling P, Dawson B, Goodman C, Landers G, Wiegerinck ET, Swinkels DW, et al. Effects of Exercise on Hepcidin Response and Iron Metabolism During Recovery. International Journal of Sport Nutrition and Exercise Metabolism. 2009 Dec;19(6):583–97.
MCCORMICK R, MORETTI D, MCKAY AKA, LAARAKKERS CM, VANSWELM R, TRINDER D, et al. The Impact of Morning versus Afternoon Exercise on Iron Absorption in Athletes. Medicine & Science in Sports & Exercise. 2019 Oct;51(10):2147–55.
McCormick R, Sim M, Dawson B, Peeling P. Refining Treatment Strategies for Iron Deficient Athletes. SportsMedicine. 2020 Oct 15;50(12):2111–23.