Clinical trial NCT04526678: Oslo Footballplayers Iron Supplementation and Training (FIT) Study
Official title: Iron Intake, Iron Status, Intestinal Health and Endurance Performance - Effects of Iron Supplementation in Young Female Football Players - a Pilot Study
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Athletes
Iron
Endurance Performance
Hemoglobin
Intestinal Health
Microbiota
Keywords: oxidative stress
football
Lead sponsor: Norwegian University of Life Sciences
Sponsor class: OTHER
Collaborators: name: Norwegian School of Sport Sciences
name: University of Oslo
name: Norwegian Olympic Sports Centre
First posted: 2020-08-26
Enrollment: 26
Sex: FEMALE
Minimum age (years): 16
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: The intervention group will ingest 27 mg iron supplement per day for three months while the control group will not ingest iron supplements.
Primary purpose: BASIC_SCIENCE

Brief summary: The aim of the study is to characterize the diet and iron status of young female elite football players and examine the relationship between iron intake, iron status, hemoglobin levels, intestinal health and sports performance. In addition, the effects of low-dose iron supplements on iron stores will be investigated and whether such supplementation affects intestinal health, microbiota composition and biomarkers for oxidative stress.

Detailed description: Iron deficiency can lead to fatigue and anemia. Because iron is necessary for the formation of new blood cells (hematopoiesis), it is an extensive practice internationally among athletes to take iron supplements in the belief that this will improve endurance performance and oxygen transport capacity by increasing red blood cell production. Although iron intake in menstruating women has shown to reduce the prevalence of anemia and iron deficiency as well as increasing hemoglobin values and iron stores. However iron supplementation increases the risk of iron excess and can result in undesirable effects such as constipation and abdominal pain as well as negative impact on intestinal epithelial permeability and increase in oxidative stress. Because iron is important for the replication and survival of almost all bacteria, with few exceptions, the intake of iron also affect the composition of the intestinal bacteria. Not surprisingly, both high and low iron levels affect the composition of the microbiota in the gut.

It is not known if young menstruating Norwegian female athletes cover their need for iron via the diet or whether extra intake in the form of a low-dose supplement could be beneficial in terms of hemoglobin levels and sports performance. Because iron preparations are not prescription and are sold in pharmacies, health food stores and larger grocery stores, this can lead to uncritical intake of iron. Since the use of iron preparations has been documented to be widespread in foreign sports environments, it is important to both characterize the iron status of Norwegian athletes and at the same time examine the beneficial value of iron supplements on sports performance as well as monitoring effects on microbiota composition and intestinal health.

The aim of the study is therefore to characterize the diet and iron status of young female elite football players and examine the relationship between iron intake, iron status, hemoglobin levels, intestinal health and sports performance. In addition, the effects of low-dose iron supplements will be investigated in relation to iron stores, hemoglobin levels and sports performance and whether such supplementation affects intestinal health, microbiota composition and biomarkers for oxidative stress.

Eligibility criteria: Inclusion Criteria:

- Female elite football players from two selected football clubs

Exclusion Criteria:

* Pregnancy
* Medical conditions that are worsened by taking iron supplements
* Already taking iron supplements

Primary outcomes:
measure: Diet composition
timeFrame: 3 months
measure: Iron intake
timeFrame: 3 months
measure: Serum Iron
timeFrame: 3 months
measure: Serum transferrin
timeFrame: 3 months
measure: Serum ferritin
timeFrame: 3 months
measure: Hemoglobin levels
timeFrame: 3 months
measure: LPS binding protein
timeFrame: 3 months
measure: Neutrophil gelatinase-associated lipocalin
timeFrame: 3 months
measure: Serum cytokines
timeFrame: 3 months
measure: Sports performance
timeFrame: 3 months
measure: Differential counts
timeFrame: 3 months
measure: Ferric reducing ability of plasma
timeFrame: 3 months
measure: Diacron reactive oxygen metabolites
timeFrame: 3 months
measure: Microbiota composition
timeFrame: 3 months
Secondary outcomes:
Other outcomes:
Locations:
city: Ås
country: Norway
facility: Norwegian University of Life Sciences
Study officials:
References: