Estimates of dietary folate and vitamin B-12 intakes are currently of considerable interest, but a valid assessment method that is faster than those currently available would better suit everyday health promotion activities.To validate a new assessment technique for estimating folate and vitamin B-12 intakes, known as the Food Choice Map (FCM), using serum folate and vitamin B-12 concentrations in a group of 95 women aged 18 to 25 years.The FCM tool was used in a cross-sectional study design to estimate the usual folate and vitamin B-12 intakes of each participant. Immediately thereafter, blood samples were taken to determine serum folate and vitamin B-12 concentrations. Subsequently, 3-day food records were completed during each of three successive weeks and used as the reference method. Using the method of triads, validity coefficients were calculated.There was no significant difference between the two methods in the correlations with serum values. FCM-obtained folate intakes (r=0.43, P<0.01) exhibited a similar and moderate association with serum folate as did 3-day food record-obtained folate intakes (r=0.39, P<0.01). Similarly, vitamin B-12 intakes obtained from both techniques showed a modest association with serum vitamin B-12 (FCM r=0.40, P<0.01; 3-day food record r=0.44, P<0.01). However, the validity coefficient for the FCM was higher than that for the 3-day food record for both folate (FCM 0.97, 3-day food record 0.79) and B-12 (FCM 0.95; 3-day food record 0.85).This study provides validation for the use of a new dietary assessment method, the FCM, for estimating folate and vitamin B-12 intakes in women of reproductive age. Larger validation studies that include men and other age groups are needed to further characterize the applicability of the FCM.