Objective To assess lutein levels of residents aged 40 years and older, and to determine whether dietary lutein intake is correlated with serum lutein concentration.
Methods Three hundred and forty-one enrolled participants were divided into three groups based on age, namely, 40-49, 50-59, and>60 years groups, and completed a quantitative food frequency questionnaire with 24-hour dietary recalls. Data from the questionnaires were used to calculate daily lutein intake. Serum concentrations of lutein were determined by high performance liquid chromatography. Then the correlation between dietary lutein intake and serum lutein concentration was evaluated.
Results The linearity of lutein was good within the range of 0.08-1.6 μg/mL, the correlation coefficient was r=0.997 3, the recovery rate was 97.85%-103.67%, intra-day and inter-day coefficients of variation were 2.32% and 3.08% respectively, and the detect limit was 0.025 μg/mL. Vegetables were the leading sources of lutein in the participants, especially spinach, leek, and broccoli. The average dietary lutein intake was (7.77& #177;2.10) mg/d, the average serum lutein concentration was (0.370& #177;0.183) μmol/L, and both were significantly lower in the>60 years group than in the 50-59 years group (P<0.05). The dietary lutein intake was negatively correlated with the triglyceride concentration (r=-0.108, P<0.05), and positively correlated with the cholesterol concentration (r=0.231, P<0.001) and the serum lutein concentration (r=0.681, P<0.001).
Conclusion There is a positive correlation between dietary lutein intake and serum lutein concentration, and the latter could be used as an indicator of individual lutein level. Elderly people should consider improving intake or supplement of lutein.
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