Fatigue in Teenage Girls: Iron Deficiency Not the Main Driver; Heavy Periods and Lifestyle Factors Linked to Fatigue

The Conversation reports on a Swedish study of 485 teenage girls examining fatigue, quality of life, menstrual patterns, diet and nicotine use, with blood tests for haemoglobin and ferritin. Iron deficiency was common (38%), but iron deficiency and anaemia did not explain fatigue. Instead, heavy periods were associated with higher fatigue and poorer quality of life, even after accounting for ferritin and haemoglobin. Skipping breakfast or lunch and daily nicotine use also correlated with fatigue. The findings suggest that fatigue in teenage girls involves modifiable factors beyond iron status. The publisher is The Conversation.

• Iron deficiency is common but not the main driver of fatigue in this group
• Heavy periods linked to greater fatigue and poorer quality of life, independent of ferritin/haemoglobin
• Skipped meals and nicotine use correlate with fatigue and wellbeing
• Implications for broader screening and health promotion

Introduction

Fatigue among teenage girls is common and often attributed to iron deficiency and anaemia, but recent work from Lund University suggests the picture is more complex.

Methods

The study followed 485 Swedish female high school students who completed questionnaires on fatigue, quality of life, menstrual patterns, diet, nicotine use and dietary supplement use. Blood samples measured haemoglobin and ferritin, markers of iron status. In earlier analyses iron deficiency was found in about 38% of participants and linked to heavy periods and low meat intake.

Findings on iron status

In the latest analyses, iron deficiency and anaemia were not associated with higher fatigue or lower quality of life. In fact, after adjusting for ferritin and haemoglobin, lower ferritin and lower haemoglobin were linked to less fatigue, suggesting iron status alone does not explain fatigue in this group.

Heavy periods and fatigue

Heavy periods were associated with greater fatigue and poorer quality of life, and this association persisted after adjusting for ferritin and haemoglobin. The researchers propose that other consequences of heavy periods—such as menstrual pain, disturbed sleep or missing school and activities—may contribute to fatigue.

Other modifiable factors

Skipping breakfast or lunch on one or more days per week and daily nicotine use (including snus or smoking) were associated with greater fatigue and poorer wellbeing, underscoring the role of lifestyle factors beyond iron deficiency.

Limitations and future work

The study lacked data on socioeconomic status, physical activity, mental health and sleep, which may also influence fatigue. Causality could not be established. The researchers plan to evaluate a newly developed five-question screening tool for iron deficiency and continue to investigate which symptoms or indicators best detect iron deficiency and which treatments work in this population.

Implications

The findings challenge the notion that teenage fatigue is primarily an iron deficiency problem and highlight actionable factors—heavy periods, meal skipping and nicotine use—that could be targeted to improve health and wellbeing.