title: Intake of isoflavone and lignan phytoestrogens and associated demographic and lifestyle factors in older Australian women.
abstract: The purpose was to determine intake of phytoestrogens in a sample of older Australian women, and to investigate associated lifestyle factors. Subjects were an age-stratified sample of 511 women aged 40-80 y, randomly selected from the electoral roll and participating in the Longitudinal Assessment of Ageing in Women at the Royal Brisbane and Women's Hospital. A cross-sectional study was conducted to assess isoflavone and lignan intake over the past month from food and supplements using a 112-item phytoestrogen frequency questionnaire. Data were also collected on nutrient intakes, physical activity, smoking, alcohol, non-prescription supplements, hormone therapy, education and occupation. Logistic regression was used to evaluate associations between demographic and lifestyle variables and soy/linseed consumption while controlling for age. Isoflavone intakes were significantly higher in the younger compared to older age groups (p<0.001); there were no age-related differences in lignan intake. Forty-five percent of women consumed at least one serve of a soy and/or linseed item and were defined as a soy/linseed consumer. Median (range) intakes by consumers for isoflavones and lignans (3.9 (0-172) mg/d and 2.4 (0.1-33) mg/d) were higher than intakes by non-consumers (0.004 (0-2.6) mg/d and 1.57 (0.44-4.7) mg/d), respectively (p<0.001). Consumers had higher intakes of dietary fibre (p=0.003), energy (p=0.04) and polyunsaturated fat (p=0.004), and higher levels of physical activity (p=0.006), socio-economic position (p<0.001), education (p<0.001) and supplement use (p<0.001). Women who consumed soy or linseed foods differed in lifestyle and demographic characteristics suggesting these factors should be considered when investigating associations with chronic disease outcomes.
authors.affiliation: School of Public Health, Queensland University of Technology, Kelvin Grove Queensland, Australia. k.hanna@qut.edu.au
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Hanna
authors.forename: Sheila
authors.initials: S
authors.lastname: O'Neill
authors.forename: Philippa M
authors.initials: PM
authors.lastname: Lyons-Wall
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000428:Alcohol Drinking; D001315:Australia; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004032:Diet / Q000379:methods / Q000706:statistics & numerical data; D019587:Dietary Supplements; D004522:Educational Status; D004651:Employment; D005260:Female; D006801:Humans; D007529:Isoflavones / Q000008:administration & dosage*; D008019:Life Style; D017705:Lignans / Q000008:administration & dosage*; D008137:Longitudinal Studies; D008875:Middle Aged; D009043:Motor Activity; D048789:Phytoestrogens / Q000008:administration & dosage*; D012907:Smoking; D012959:Socioeconomic Factors
chemical_list: D007529:Isoflavones; D017705:Lignans; D048789:Phytoestrogens