Sex-based Differences in Hematological and Iron-Status Biomarkers, Nutritional Factors, and Anemia Status among Adolescents at the Higher Institute of Health Sciences, Al-Marj, Libya

Abstract

Background: Adolescence is a nutritionally vulnerable period in which rapid growth, expansion of blood volume, increasing lean body mass, and—after menarche—recurrent menstrual blood loss raise iron requirements. Iron deficiency may develop before overt anemia and may affect fatigue, exercise capacity, attention, and academic performance. A combined assessment of hemoglobin, red-cell indices, ferritin, transferrin saturation, and soluble transferrin receptor can therefore characterize iron status more completely than hemoglobin alone.

Objective: To compare hematological and biochemical iron-status markers between adolescent girls and boys at the Higher Institute of Health Sciences, Al-Marj, Libya, and to describe anemia status, nutrition knowledge, food-related iron awareness, nutritional-status categories, and physical activity.

Methods: An institution-based cross-sectional study included 75 adolescents assessed from October 2024 through May 2025. The sample comprised 50 girls (66.7%) and 25 boys (33.3%). Descriptive variables were summarized as frequency and percentage. Hematological and iron-status markers were summarized as mean ± standard deviation. The investigator-provided anemia classification and p values were retained, while arithmetic percentages were independently checked for internal consistency.

Results: Forty of 75 participants were classified as anemic (53.3%) and 35 as not anemic (46.7%). Anemia affected 31/50 girls (62.0%) and 9/25 boys (36.0%), with a significant sex association (Pearson χ² p=0.033). Low nutrition knowledge was reported in 58.7%, 50.7% lacked awareness of iron-boosting foods, and 62.7% lacked awareness of iron-inhibiting foods. Girls had lower Hb, Hct, MCV, MCH, serum iron, transferrin saturation, and ferritin and higher transferrin, sTfR, and sTfR/log ferritin index than boys. Mean ferritin was 14.01 ± 13.26 ng/mL in girls versus 73.81 ± 44.37 ng/mL in boys (reported p<0.0001).

Conclusion: The study demonstrates a high anemia burden and a coherent female-predominant pattern of lower iron stores and iron-restricted erythropoiesis. The findings support combined laboratory screening together with menstrual and nutrition assessment, while highlighting the need for verification of individual diagnostic thresholds and collection of raw participant-level data for adjusted analyses.