Associations of dietary, lifestyle, and sociodemographic factors with iron status in Chinese adults: a cross-sectional study in the China Health and Nutrition Survey

Background: Although a high prevalence of anemia and related disease burden have been documented in China, limited evidence is available on the current population-level iron status and risk factors for iron imbalance. Objective: We explored the associations of dietary, lifestyle, and sociodemographic factors with iron status in Chinese adults. Design: Our study population consisted of 7672 adults aged 1865 y from the 2009 China Health and Nutrition Survey. Diet was assessed with the use of 3 consecutive 24-h dietary recalls. Serum ferritin, serum transferrin receptor, and hemoglobin concentrations were measured. Results: The geometric means +/- SDs for ferritin concentrations were 135.9 +/- 2.7 ng/mL in men and 42.7 +/- 3.1 ng/mL in women. After adjustment for potential risk factors, including high-sensitivity C-reactive protein concentration, the association between age and ferritin concentration was inverse in men (P-trend < 0.001) and positive in women (P-trend < 0.001). We observed a positive association between body mass index (in kg/m(2)) and ferritin concentration in both men and women (both P-trends < 0.001). Dietary phytate intake was inversely associated with ferritin concentration in men (P-trend = 0.002) but not in women. Red meat consumption was positively associated with ferritin concentration both in men (P-trend = 0.002) and in older women (P-trend = 0.009). Lower intakes of grains and higher intakes of pork and poultry were associated with higher ferritin concentrations (all P-trends <= 0.05) in men but not in women. We observed variations in ferritin concentrations across different geographic regions (both P <= 0.01). Conclusions: Serum ferritin concentrations varied across different sociodemographic, lifestyle, and dietary factors in this Chinese population. A higher intake of red meat was associated with higher ferritin concentrations in men and older women.