Folate intake of the Dutch population according to newly established liquid chromatography data for foods

Abstract

Determining folate intake is difficult because existing folate data in food-composition tables are scarce and unreliable. The purposes of this study were first to analyze 125 of the most important foods that contribute to folate intake in the Netherlands and second to estimate the folate intake of a representative sample of the population. We analyzed the folate content of foods by using a newly developed HPLC trienzyme method combined with an affinity chromatography cleanup step. These results were then used to estimate the folate intake of persons aged 1-92 y who participated in the second Dutch National Food Consumption Survey (DNFCS) in 1992 (n = 6218). For 35 important folate-containing foods, the mean relative folate contents measured by HPLC were 66%, 80%, and 77% of values for comparable foods included in the British food-composition table; the Ministry of Agriculture, Fisheries and Food table; and the US Department of Agriculture database, respectively. P values for comparison of relative values with 100% were 0.001, 0.171, and 0.144, respectively. The mean dietary folate intake of the DNFCS participants was 182 +/- 119 microg/d. Intake of supplement users (n = 86) was 344 microg/d, with 147 microg/d from supplements. On the basis of these findings, 42% of men and 54% of women do not meet current Dutch recommendations of 60 microg/d for children and 200 microg/d for adults. Total folate quantities in foods, analyzed by HPLC, are approximately 25% lower than amounts listed in recent food-composition tables estimated by use of the microbiological method. On the basis of these new data, approximately 50% of a representative Dutch population sample does not meet the current recommendations for folate intake.