Reportedly, skipping breakfast induces various health problems, including low fat-free mass, low bone mineral density, and dysmenorrhea. These health problems develop from decreased daily energy and nutrient intake because of skipping breakfast. Consequently, skipping breakfast may cause other health concerns, such as poor glucose, lipid, and iron metabolism among young female workers.

 [Purpose] This study aimed to clarify the association between breakfast eating habits and serum glucose, lipid, and iron metabolism markers among young female workers.

 [Methods] The participants were 22 young female workers divided into the breakfast eaters (n = 11, age 30 ± 3 years, body mass index [BMI] 20.6 ± 1.8 kg/m²) and breakfast skippers (n = 11; age 28 ± 6 years, BMI 20.2 ± 1.6 kg/m²). We collected information on energy, nutrient, and food group intakes, serum glucose, lipid, and iron metabolism markers, and body composition using the dietary record, biochemical analysis, and bioelectrical impedance method, respectively.

 [Results] The breakfast skippers had significantly lower energy (kcal/day), protein (g/day), carbohydrate (g/day), and grain (g/day) intakes than that of the breakfast eaters. Serum glucose and lipid markers showed no significant difference between the two groups. In biochemical blood indices, the serum ferritin (ng/dL) and mean corpuscular hemoglobin (MCH) (pg) in the breakfast skippers were significantly lower. As serum ferritin < 20 ng/dL and MCH < 28.6 pg were screened for early iron deficiency, the breakfast skippers had a higher proportion of those below the cutoff values than that of the breakfast eaters for both blood indices.

 [Conclusion] Skipping breakfast is associated with iron deficiency in young female workers. Iron deficiency is a common disease with a high morbidity rate among young Japanese women, which is related to various health issues. Therefore, health promotion is necessary to increase the importance of eating breakfast in Japan.