Evaluation of a 2-day food record to determine iron, calcium and vitamin C intake in young Belgian women.

OBJECTIVE: Evaluation of a 2-day food record (FR) for the assessment of iron, calcium and vitamin C intake. DESIGN: In a subsample of a large-scale epidemiological study, iron, calcium and vitamin C intake were estimated using a 2-day FR and compared to the nutrient intakes assessed by an 11-day FR (reference method). SETTING: City of Ghent, Dutch speaking part of Belgium. SUBJECTS: A number of 51 non-pregnant women (18-39 years). RESULTS: Mean iron, calcium and vitamin C intakes were not significantly different between the reference method and 2-day FR. Correlation coefficients of 0.63 (iron) and 0.76 (calcium, vitamin C) were reached. The iron intake of 95% of the individuals assessed by the 2-day FR varied between 5 mg above or below the reference intake. Over 50% of the women were correctly classified and 4% or fewer were extremely misclassified by the 2-day FR. Mean 11-day FR intakes increased progressively over the tertiles defined by the 2-day FR. The 11-day energy intake was under-reported by 28% of the women; no over-reporters were identified. CONCLUSIONS: The 2-day FR is able to estimate mean iron, calcium and vitamin C intake and to rank individuals along the distribution of intakes.

Iron intake in relation to diet and iron status of young adult women.

AIMS: To determine the iron intake and food sources of iron in young adult women and to compare women with high versus low iron intake on diet and iron status. METHODS: Iron intake and food sources were assessed by a 2-day estimated food record. Iron status was determined by a fasting venous blood sample. Differences in diet and iron status between women with high versus low iron intake were examined by comparing women of the fourth respectively first quartile of total iron intake (mg/day). RESULTS: The median total, heme and non-heme iron intake was 10.6, 0.6 and 9.8 mg/day, respectively. The median iron intake was 93 and 131% of the estimated average requirement (EAR) of the UK (11.4 mg/day) and USA (8.1 mg/day), respectively. The most important iron intake contributors were cereals and cereal products (31%), meat and meat products (12%) and vegetables (10%). Women with a high iron intake showed a significantly higher energy-adjusted intake of alcoholic beverages and soups and a lower intake of non-alcoholic beverages than women with a low iron intake. Approximately 5% of the women had anemia, of which 3% had iron deficiency anemia (IDA). Almost 20% was iron-deficient non-anemic. In this regard, no significant differences were found between the iron intake quartiles. CONCLUSION: The median iron intake in this study population is considerably below the national recommended dietary allowance (20 mg/day). However, based on the approach of the Dietary Guidelines Advisory Committee, iron intake seems to pose no major health problem when using the EAR as a reference. The number of women with IDA was indeed not alarming (3%), although 20% was iron-deficient non-anemic. The question remains whether an increase in iron intake can improve iron status.

Iron intake and dietary sources of iron in Flemish adolescents.

OBJECTIVE: To investigate the dietary iron intake and food sources of iron in Flemish adolescents. DESIGN: Cross-sectional survey; dietary assessment method: a 7-day estimated food record. SETTING: Private and public secondary schools in Ghent, a city in the Dutch-speaking part of Belgium. SUBJECTS: A total of 341 adolescents (129 boys and 212 girls), 13-18 y, randomly selected by a multistage clustered sampling technique. RESULTS: The mean total iron intake (s.d.) for boys was 13.4 (+/- 2.91) mg/day and for girls 10.1 (+/- 2.79) mg/day. A proportion of 38.8% of the boys and 99.5% of the girls had a mean total iron intake below the Belgian Recommended Dietary Allowance and 3.1% of the boys and 71.2% of the girls below the British Estimated Average Requirement. When bioavailable iron intake is considered, 84.5% of the boys and only 16.5% of the girls met the age-specific requirement. The food groups with the highest mean proportional contribution to total iron intake in both males and females were bread, meat and meat products, cereals and potatoes. A comparison of adolescents from the highest tertile of iron intake (mg/day) with adolescents from the lowest tertile showed a significantly higher energy-adjusted intake of brown bread and a significantly lower intake of soft drinks in the former group in both boys and girls. A significantly higher energy-adjusted intake of breakfast cereals in adolescents of the highest tertile than those of the lowest tertile was seen in girls only. Analyses in consumers only did not change this overall picture. CONCLUSIONS: One can conclude that the mean iron intake of Flemish girls is considerably lower than the current recommendations. An increased iron intake in this subgroup of the population is therefore advisable.

Validity and reproducibility of a computerised tool for assessing the iron, calcium and vitamin C intake of Belgian women.

OBJECTIVE: To determine the relative validity of a newly developed iron intake assessment tool, designed specifically to assess iron, calcium and vitamin C intake. DESIGN: Estimates of iron, calcium and vitamin C intake from a computerised iron intake assessment tool compared with those from 11-day estimated dietary records. SETTING: Region of Ghent (N= +/- 225,000), a city in Flanders, the Dutch-speaking part of Belgium. SUBJECTS: In all, 50 women aged 18-39 y, participating in a large-scale epidemiological study on iron intake and iron status. MAIN RESULTS: Mean dietary iron intake from the 11-day food record, the unadjusted dietary iron intake assessment tool and the adjusted tool was, respectively, 10.5 +/- 2.7, 10.4 +/- 4.3 and 9.6 +/- 2.9 mg. For the different nutrients, the correlation coefficients vary from 0.45 to 0.60 for adjusted intake. The mean difference of iron intake by the two methods (0.8 +/- 2.9 mg) did not differ significantly from zero. The new method correctly classified 38% (iron), 38% (calcium) and 58% (vitamin C) of the subjects to the correct tertile. The correlation coefficients ranged from 0.48 for adjusted vitamin C intake to 0.73 for adjusted calcium intake between two administrations. CONCLUSION: The newly developed instrument can be used to assess mean group intakes of iron, calcium and vitamin C in women consuming a Western diet. However, since the ranking capability of the new tool is rather weak, further refinement of the tool is required to produce a robust method for assessing iron, calcium and vitamin C intakes of individuals. SPONSORSHIP: This research was supported by the Belgian National Fund for Scientific Research/Flemish Division (Fund No G.0152.01).