['We assessed the impact of vitamin D on hemoglobin levels in Korean adults, considering gender and menopausal status.', 'We analyzed 2528 men and 3258 women divided into quartiles of vitamin D from the Fifth Korean National Health and Nutrition Examination Survey 2010. Anemia was defined as a hemoglobin level of <13 g/dl in men and <12 g/dl in women.', 'Pre- and post-menopausal women in the lowest 25-hydroxyvitamin D group were at an increased risk of anemia, after adjusting for confounding factors (OR (95% CI); Premenopausal: Q1 (≥18.45 ng/ml), 1; Q2 (14.69-18.44 ng/ml), 1.120 (0.745, 1.683); Q3 (11.93-14.68 ng/ml), 1.427 (0.963, 2.116); and Q4 (≤11.92 ng/ml), 1.821 (1.240, 2.673); P=0.009; and Post: Q1 (≥22.04 ng/ml), 1; Q2 (16.92-22.03 ng/ml), 1.106 (0.697, 1.756); Q3 (13.37-16.91 ng/ml), 1.167 (0.740, 1.839); and Q4 (≤13.36 ng/ml), 1.583 (1.026, 2.447); P=0.038). In addition, pre- and post-menopausal women in the lower 25-hydroxyvitamin D group were at a higher risk of iron deficient anemia and anemia of inflammation. However, post-menopausal women did not show a higher risk of anemia with CKD (P=0.470). Men with the lowest 25-hydroxyvitamin D levels did not show a higher risk of anemia (P=0.528).'] Do low vitamin D levels increase anemia risk in Korean women?