Within the DietCompLyf database, participants were asked to record which supplements they consumed as part of the Food Frequency Questionnaire. This database contains 3393 unique entries of brand names and product name information (all information has been transcribed exactly as entered within the patient records, therefore some typographical inconsistencies are observed – these are being standardised as part of the coding process). The processing work being completed to compile a coding structure has been organised as follows:
- Supplement Manufacturers Information: We have 320 unique supplement manufacturers listed in our database (estimates from raw data, subject to quality checks as outlined above). For each manufacturer, contact details (online address; address; email; telephone number) are being compiled to enable contact with individual producers and/or suppliers to gather product composition information (Supplement Manufacturers Contact List.xlsx).
- Supplement Coding Framework: Each unique product code is being matched as closely as possible to the following details:
- Ingredient information: It is expected that several phytoestrogen sources will be included within supplements, and as nutrient composition databases do not currently detail ‘nutrient contents’ for individual or total phytoestrogens, our intention is to collect as much detail as possible to note the sources of phytoestrogens consumed by our sample within supplements. This will enable analysis by intake without (at this stage) quantification of intakes using dietary supplement databases. Ingredients known to be sources of phytoestrogens and which are included in dietary supplements include (but are not limited to) black cohosh (Cimicifuga racemosa), dong quai (Angelica sinensis), red clover (Trifolium pratense), alfalfa (Medicago sativa), licorice (Glycyrrhiza glabra), Korean ginseng (Panax ginseng), wild American ginseng (Panax quinquefolius) and Kudzu root (Puerariae lobata).
- Nutrient information: Although we cannot quantify intakes of phytoestrogens within dietary supplements without biochemical analysis, a depth of evidence exists to suggest that dietary supplements contribute a great deal towards other nutrient intakes: 319% more vitamin D, 77% more calcium and 36% more magnesium were estimated when dietary supplements were included in nutrient intake estimates from the 1997-1998 Food Habits of Canadians survey for example (Tropmann et al., 2002). Within the American INTERMAP sample, male supplement users consumed 78.5% more vitamin C and 50.2% more folate than non-consumers; female users consumed 79.2% and 54.5% more respectively (Archer et al., 2005). For this reason, nutrient intakes from dietary supplements consumed by all DietCompLyf participants will also be ‘nutrient coded’ to ensure intake estimates incorporate both food, alcohol and supplements within their estimates.
- Recommended dose information: All women in DietCompLyf were asked to record how much of individual supplements they consumed. For completeness, information will be recorded for all supplement labels to enable an assessment of whether women followed recommended dosages, and as a means of assessing the precision of the ‘match’ to existing products for example.
Tropmann L, Johns T, Gray-Donald K. Natural health product use in Canada. Canadian Journal of Public Health 2002;93(6):426-30.
Archer S, Stamler J, Moag-Stahlberg A, Van Horn L, Garside D, Chan Q, Buffington J, Dyer A. Association of dietary supplement use with specific micronutrient intakes among middle-aged American men and women: The INTERMAP study. J Am Diet Assoc 2005;105:1106-14.