Fatigue in teenage girls linked to heavy periods and lifestyle, not iron deficiency

by Moa Wolff, Anna Stubbendorff, The Conversation

edited by Lisa Lock, reviewed by Andrew Zinin

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Fatigue is common among teenage girls and can have a substantial impact on their everyday lives, including school attendance and social functioning.

Iron deficiency and anemia are often considered the most probable explanations for the fatigue symptoms teenage girls experience. But our recent findings suggest that the cause is more complicated.

We studied 485 Swedish female high school students. Participants completed questionnaires about fatigue, quality of life, menstrual patterns, diet, nicotine use and dietary supplement use. They also provided blood samples to measure hemoglobin and ferritin—key markers used to assess iron status. Low ferritin and low hemoglobin levels typically indicate iron deficiency and anemia, respectively.

In earlier analyses of the same group, we found iron deficiency was present in 38% of participants. It was strongly associated with both heavy periods (reported by 54% of participants) and eating a diet with little or no meat (reported by 27% of participants).

In our latest study, participants reported experiencing high levels of fatigue. However, our analyses revealed that neither iron deficiency nor anemia was associated with higher levels of fatigue or lower quality of life.

In fact, the opposite was true. Lower ferritin and lower hemoglobin levels were linked to less fatigue—even after accounting for confounding factors.

Instead, we found that heavy periods were associated with greater fatigue and poorer quality of life. This was true even after adjusting for ferritin and hemoglobin levels.

This suggests that the association between heavy periods and fatigue is not explained by iron deficiency or anemia. Other consequences of heavy periods—such as menstrual pain, disturbed sleep or missing school, sports and social activities—may instead contribute.

Skipping breakfast, lunch or both meals on one or more days per week was also associated with greater fatigue and poorer well-being. Daily nicotine use, including snus or smoking, was likewise associated with greater fatigue and poorer well-being.

These are important results because heavy periods, skipped meals and nicotine use are modifiable factors that may be overlooked if iron deficiency is assumed to be the only cause of fatigue.

Understanding fatigue

Our study did not capture everything that might influence fatigue. For example, we lacked information on socioeconomic status, physical activity levels, mental health and sleep—factors that may also be related to fatigue.

We also cannot determine cause or effect. For instance, girls may skip breakfast because they're tired. Nicotine use may be a marker of other lifestyle factors linked to fatigue—rather than a direct cause of fatigue.

Iron deficiency still matters, however. It's the leading cause of anemia worldwide. Iron is essential for transporting oxygen to the organs, good muscle health and normal brain function.

Teenage girls are particularly prone to iron deficiency because their iron needs increase during growth. Menstruation and dietary habits can further reduce iron stores.

Our research will now evaluate a newly developed five-question screening tool for identifying iron deficiency. We will also continue to investigate which symptoms or other indicators are most useful for detecting iron deficiency and which treatment strategies work best in this population.

These novel results matter because fatigue in teenage girls is often reduced to a question of iron deficiency. Our findings suggest that the picture is more complex. Heavy periods, skipped meals and nicotine use are common and potentially modifiable factors. Overlooking them may mean missing important opportunities to support teenage girls' health and well-being.

Key medical concepts

FatigueIron DeficienciesMenorrhagiaAnemia

Clinical categories

Obstetrics & gynecologyChildren's healthPediatricsReproductive healthHealthy living Provided by The Conversation Who's behind this story?

Lisa Lock

BA art history, MA material culture. Former museum editor, paramedic, and transplant coordinator. Editing for Science X since 2021. Full profile →

Andrew Zinin

Master's in physics with research experience. Long-time science news enthusiast. Plays key role in Science X's editorial success. Full profile →

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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