title: Dairy food consumption, blood pressure and retinal microcirculation in adolescents.
abstract: OBJECTIVE
  The relationship between dairy food consumption and dietary calcium intake, and vascular risk factors during adolescence remains unclear. We aimed to prospectively assess whether dairy food consumption (milk, cheese, yoghurt) is associated with blood pressure (BP) and retinal microvascular signs among adolescents.
  
  
  RESULTS
  As many as 2353 and 1216 participants aged 12 and 17, respectively, were examined. Longitudinal analyses involved 888 subjects with complete baseline and follow-up data. Dairy consumption was assessed from validated semi-quantitative food frequency questionnaires. BP information was collected and retinal vessel caliber was quantified from digital photographs using computer software. In girls, after multivariable adjustment, each serve/day increase in total dairy intake was concurrently associated with 1.04 (p = 0.03) and 1.10 mm Hg (p = 0.02) decreases in mean diastolic and arterial BP, respectively. Also in girls, each serve/day increase in cheese intake over 5 years was concurrently related to 7.18 (p = 0.001), 5.28 (p = 0.002) and 5.79 mm Hg (p = 0.001) decrease in mean systolic, diastolic and arterial BP, respectively. Among girls, each 100 mg/day increase in dietary calcium intake was associated with a concurrent 0.5 (p = 0.01) and 0.3 mm Hg (p = 0.02) decrease in mean systolic and arterial BP, respectively. Cross-sectionally, adolescents in the highest versus lowest tertile of yoghurt intake had ∼ 1.3 μm wider retinal arterioles (p = 0.05) and ∼ 2.0 μm narrower venules (p = 0.04).
  
  
  CONCLUSIONS
  Consumption of dairy products, particularly cheese, could have a beneficial effect on BP, particularly among girls.
authors.affiliation: Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Australia. Electronic address: bamini.gopinath@sydney.edu.au.
authors.forename: B
authors.initials: B
authors.lastname: Gopinath
authors.affiliation: Faculty of Health Sciences, University of Sydney and St Vincent's Hospital, Australia.
authors.forename: V M
authors.initials: VM
authors.lastname: Flood
authors.affiliation: Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Burlutsky
authors.affiliation: Faculty of Science, Medicine and Health, University of Wollongong, Australia.
authors.forename: J C Y
authors.initials: JC
authors.lastname: Louie
authors.affiliation: University of Sydney Clinical School, The Children's Hospital at Westmead, Australia; School of Public Health, University of Sydney, Australia.
authors.forename: L A
authors.initials: LA
authors.lastname: Baur
authors.affiliation: Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Mitchell
mesh_terms: D000293:Adolescent; D001794:Blood Pressure; D002136:Calcium, Dietary / Q000008:administration & dosage*; D002648:Child; D003430:Cross-Sectional Studies; D003611:Dairy Products; D004032:Diet; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008833:Microcirculation; D015999:Multivariate Analysis; D015596:Nutrition Assessment; D011446:Prospective Studies; D012171:Retinal Vessels / Q000502:physiology*; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D002136:Calcium, Dietary
keywords: Blood pressure; Calcium; Dairy; Retinal vessels; Sydney Childhood Eye Study