Intakes of culinary herbs and spices from a food frequency questionnaire evaluated against 28-days estimated records

BACKGROUND: Worldwide, herbs and spices are much used food flavourings. However, little data exist regarding actual dietary intake of culinary herbs and spices. We developed a food frequency questionnaire (FFQ) for the assessment of habitual diet the preceding year, with focus on phytochemical rich food, including herbs and spices. The aim of the present study was to evaluate the intakes of herbs and spices from the FFQ with estimates of intake from another dietary assessment method. Thus we compared the intake estimates from the FFQ with 28 days of estimated records of herb and spice consumption as a reference method. METHODS: The evaluation study was conducted among 146 free living adults, who filled in the FFQ and 2-4 weeks later carried out 28 days recording of herb and spice consumption. The FFQ included a section with questions about 27 individual culinary herbs and spices, while the records were open ended records for recording of herbs and spice consumption exclusively. RESULTS: Our study showed that the FFQ obtained slightly higher estimates of total intake of herbs and spices than the total intake assessed by the Herbs and Spice Records (HSR). The correlation between the two assessment methods with regard to total intake was good (r = 0.5), and the cross-classification suggests that the FFQ may be used to classify subjects according to total herb and spice intake. For the 8 most frequently consumed individual herbs and spices, the FFQ obtained good estimates of median frequency of intake for 2 herbs/spices, while good estimates of portion sizes were obtained for 4 out of 8 herbs/spices. CONCLUSIONS: Our results suggested that the FFQ was able to give good estimates of frequency of intake and portion sizes on group level for several of the most frequently used herbs and spices. The FFQ was only able to fairly rank subjects according to frequency of intake of the 8 most frequently consumed herbs and spices. Other studies are warranted to further explore the intakes of culinary spices and herbs.