title: Dietary acid load, trabecular bone integrity, and mineral density in an ageing population: the Rotterdam study.
abstract: We studied the relation between a diet that is high in acid-forming nutrients (e.g. proteins) and low in base-forming nutrients (e.g. potassium) and bone structure. We showed a negative relation, which was more prominent if proteins were of animal rather than of vegetable origin and if intake of dietary fibre was high.
  
  
  
  Studies on dietary acid load (DAL) and fractures have shown inconsistent results. Associations between DAL, bone mineral density (BMD) and trabecular bone integrity might play a role in these inconsistencies and might be influenced by renal function and dietary fibre intake. Therefore, our aim was to study (1) associations of DAL with BMD and with the trabecular bone score (TBS) and (2) the potential influence of renal function and dietary fibre in these associations.
  
  
  
  Dutch individuals aged 45 years and over (n = 4672) participating in the prospective cohort of the Rotterdam study were included. Based on food frequency questionnaires, three indices of DAL were calculated: the net endogenous acid production (NEAP) and the ratios of vegetable or animal protein and potassium (VegPro/K and AnPro/K). Data on lumbar spinal TBS and BMD were derived from dual-energy X-ray absorptiometry measurements.
  
  
  
  Independent of confounders, NEAP and AnPro/K, but not VegPro/K, were associated with low TBS (standardized β (95%) = -0.04 (-0.07, -0.01) and -0.08 (-0.11, -0.04)) but not with BMD. Associations of AnPro/K and VegPro/K with TBS were non-linear and differently shaped. Unfavourable associations between NEAP, BMD and TBS were mainly present in subgroups with high fibre intake.
  
  
  
  High NEAP was associated with low TBS. Associations of AnPro/K and VegPro/K and TBS were non-linear and differently shaped. No significant associations of DAL with BMD were observed, nor was there any significant interaction between DAL and renal function. Mainly in participants with high intake of dietary fibre, DAL might be detrimental to bone.
authors.affiliation: Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands.|Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands.
authors.forename: E A L
authors.initials: EAL
authors.lastname: de Jonge
authors.affiliation: Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands.|Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Koromani
authors.affiliation: Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands.|Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Hofman
authors.affiliation: Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands.|Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands.
authors.forename: A G
authors.initials: AG
authors.lastname: Uitterlinden
authors.affiliation: Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands.
authors.forename: O H
authors.initials: OH
authors.lastname: Franco
authors.affiliation: Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Rivadeneira
authors.affiliation: Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands. j.c.kiefte-dejong@erasmusmc.nl.|Department of Global Public Health, Leiden University College, The Hague, The Netherlands. j.c.kiefte-dejong@erasmusmc.nl.|Department of Paediatrics, Erasmus MC, Rotterdam, The Netherlands. j.c.kiefte-dejong@erasmusmc.nl.
authors.forename: J C
authors.initials: JC
authors.lastname: Kiefte-de Jong
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000143:Acids / Q000378:metabolism*; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000502:physiology*; D000071556:Cancellous Bone / Q000502:physiology*; D003430:Cross-Sectional Studies; D004032:Diet / Q000706:statistics & numerical data*; D004043:Dietary Fiber / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006801:Humans; D008159:Lumbar Vertebrae / Q000502:physiology; D008297:Male; D008875:Middle Aged; D017419:Potassium, Dietary / Q000008:administration & dosage; D012959:Socioeconomic Factors
chemical_list: D000143:Acids; D004043:Dietary Fiber; D004044:Dietary Proteins; D017419:Potassium, Dietary
keywords: BMD; Dietary acid load; Dietary fibre; Renal function; Trabecular bone score