title: Dietary phosphorus intake is negatively associated with bone formation among women and positively associated with some bone traits among men-a cross-sectional study in middle-aged Caucasians.
abstract: High dietary phosphorus (P) intake has acute negative effects on calcium (Ca) and bone metabolism, but long-term clinical data are contradictory. We hypothesized that high P intake is associated with impaired bone health as suggested by earlier short-term studies on bone metabolism. In this cross-sectional study, we investigated associations between dietary P intake, bone traits in the radius and tibia, and bone turnover in a population-based sample of 37- to 47-year-old Caucasian premenopausal women (n=333) and men (n=179) living in Southern Finland (60°N). We used various regression models in an "elaboration approach" to elucidate the role of P intake in bone traits and turnover. The addition of relevant covariates to the models mainly removed the significance of P intake as a determinant of bone traits. In the final regression model (P intake, weight, height, age, Ca intake, serum 25-hydroxyvitamin D, physical activity, smoking, contraceptive use in women), P intake was slightly positively associated only with bone mineral content and cross-sectional cortical bone area in the tibia of men. Among women, inclusion of Ca removed all existing significance in the crude models for any bone trait. In women P intake was negatively associated with the bone formation marker serum intact pro-collagen type I amino-terminal propeptide, whereas no association was present between P intake and bone turnover in men. In conclusion, these findings disagree with the hypothesis; P intake was not deleteriously associated with bone traits; however, P intake may negatively contribute to bone formation among women.
authors.affiliation: Calcium Research Unit, Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Suvi T
authors.initials: ST
authors.lastname: Itkonen
authors.affiliation: Department of Forest Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Hannu J
authors.initials: HJ
authors.lastname: Rita
authors.affiliation: Calcium Research Unit, Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Elisa M
authors.initials: EM
authors.lastname: Saarnio
authors.affiliation: Calcium Research Unit, Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Virpi E
authors.initials: VE
authors.lastname: Kemi
authors.affiliation: Calcium Research Unit, Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Heini J
authors.initials: HJ
authors.lastname: Karp
authors.affiliation: Calcium Research Unit, Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Merja U M
authors.initials: MU
authors.lastname: Kärkkäinen
authors.affiliation: Folkhälsan Institute of Genetics, Helsinki, Finland.
authors.forename: Minna H
authors.initials: MH
authors.lastname: Pekkinen
authors.affiliation: Department of Obstetrics and Gynaecology, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: E Kalevi
authors.initials: EK
authors.lastname: Laitinen
authors.affiliation: Department of Clinical Chemistry, University of Oulu, Oulu, Finland; Northern Finland Laboratory Centre Nordlab, Oulu, Finland; Medical Research Center, Oulu, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Risteli
authors.affiliation: Department of Clinical Chemistry, University of Oulu, Oulu, Finland; Northern Finland Laboratory Centre Nordlab, Oulu, Finland; Medical Research Center, Oulu, Finland.
authors.forename: Marja-Kaisa
authors.initials: MK
authors.lastname: Koivula
authors.affiliation: The UKK Institute for Health Promotion Research, Tampere, Finland.
authors.forename: Harri
authors.initials: H
authors.lastname: Sievänen
authors.affiliation: Calcium Research Unit, Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland. Electronic address: christel.lamberg-allardt@helsinki.fi.
authors.forename: Christel J E
authors.initials: CJ
authors.lastname: Lamberg-Allardt
mesh_terms: D000328:Adult; D015519:Bone Density; D016723:Bone Remodeling / Q000187:drug effects*; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D002136:Calcium, Dietary / Q000008:administration & dosage / Q000494:pharmacology; D024042:Collagen Type I / Q000097:blood; D003430:Cross-Sectional Studies; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010012:Osteogenesis / Q000187:drug effects*; D010024:Osteoporosis; D016226:Phosphorus, Dietary / Q000009:adverse effects / Q000494:pharmacology*; D017697:Premenopause; D011884:Radius / Q000187:drug effects / Q000378:metabolism; D012737:Sex Factors; D013977:Tibia / Q000187:drug effects / Q000378:metabolism; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D044465:White People
chemical_list: D002136:Calcium, Dietary; D024042:Collagen Type I; D016226:Phosphorus, Dietary; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Bone mineral density; Bone turnover markers; Calcium; Cross-sectional study; Peripheral quantitative computed tomography; Phosphorus