Declining Iron Levels in Women in Military

After five months of basic military training, the proportion of female recruits with iron deficiency had more than doubled, from 25% to 55%. According to the researchers, this study calls for increased attention and action to improve iron levels.

The study, published in the journal BMJ Military Health, is based on surveys of conscripts at the Command and Control Regiment in Enköping. The regiment is a common resource in command and control for the entire Swedish Armed Forces.

The study measured the iron levels at baseline and after five months of basic military training. Out of 112 women and 148 men at the first measurement, a majority, 58 women and 104 men, volunteered to participate in a second round of sampling and testing.

The study shows that the prevalence of iron deficiency, around 25%, is as high among female conscripts as in the rest of society for the given age group. The same was true for the proportion of women with anemia due to iron deficiency, known as iron deficiency anemia, with an incidence of 8%.

Marked increase in iron deficiency

Remarkably, the proportion of female conscripts with iron deficiency more than doubled, from 25 to 55% over the five-month study period. The proportion of conscripted men with iron deficiency increased from 4 to 7 percent.

Levels of hemoglobin, often abbreviated as Hb, generally increased during the study period. Hemoglobin is responsible for oxygen transport in the blood. However, levels of ferritin, a measure of iron deposits in the body, fell in both women and men. The decrease was significantly greater for women than for men.

The study also found that high physical work capacity at the time of enlistment was related to a lower risk of having adapted service. Adapted service means that a soldier does not fully participate in intensive training sessions, often due to injury or illness. Adapted service can be seen as a risk factor for completely discontinuing the training.

Attention and action

The study is a collaboration between the Sahlgrenska Academy at the University of Gothenburg, Sahlgrenska University Hospital, the Swedish School of Sport and Health Sciences (GIH) in Stockholm, the Swedish Armed Forces Center for Defense Medicine in Gothenburg and the Command and Control Regiment in Enköping.

The study is the first to show a high prevalence of iron deficiency both before and after basic military training in Sweden. Iron deficiency is often accompanied by various combinations of fatigue, lethargy, attention deficit, dizziness, headaches etc. Iron levels are mainly influenced by the diet, which should be varied and rich in iron including from animal sources, and by blood loss during periods among women.

"The results of the study highlight the importance of paying attention to iron levels and potential iron deficiency among conscripts, and to discuss causes and measures that should be implemented," says Fabian Taube, Adjunct Lecturer at the University of Gothenburg, Medical Research Advisor at the Swedish Armed Forces Center for Defense Medicine and the first author of the study.

"Given the central role of iron in health, this is an important discussion that not only concerns the Armed Forces," says Ingrid Larsson, Associate Professor of Clinical Nutrition at the University of Gothenburg, Dietitian at Sahlgrenska University Hospital and one of the co-authors.

Study: Changes in haemoglobin and ferritin levels during basic combat training: relevance for attrition and injury frequency,