title: Individual efforts to reduce salt intake in China, Japan, UK, USA: what did people achieve? The INTERMAP Population Study.
abstract: OBJECTIVE
  Habitual high-salt intake raises blood pressure and risk of cardiovascular diseases. To prevent/control these risks, reduced salt diet (RSD) is recommended in many countries and some people report practicing it; however, little is known about actual achievement. This population-based study assessed level of 24-h dietary sodium intake of participants reporting RSD and others.
  
  
  METHODS
  Participants were 4680 men and women ages 40-59 years randomly selected from 17 populations in People's Republic of China (PRC), Japan, UK and USA, for an observational study on diet and blood pressure (INTERMAP). Daily sodium intake was determined by two timed 24-h urine collections. Antihypertensive treatment status and RSD were ascertained by questionnaire.
  
  
  RESULTS
  Participants reporting RSD were few; 3.1% (Japan), 1.3% (PRC), 2.5% (UK), 7.2% (USA); 15.1, 7.9, 16.7 and 16.8% of people with treated hypertension. For those reporting RSD, 24-h urinary sodium excretion was significantly, but only modestly lower than for others, by 17.9 mmol/day (Japan), 56.7 (PRC) and 14.7 (USA), but higher by 10.5 in UK. Sodium intakes for participants reporting RSD remained higher than recommended; 181.0 mmol/day (Japan), 171.5 (PRC), 155.2 (UK) and 148.9 (USA). For these people, as for others, main sources of salt were processed foods in Japan, UK and USA; in PRC, salt added in preparation at home.
  
  
  CONCLUSIONS
  Enhanced sustained efforts are needed to raise general awareness of the harmful effects of salt on health and the benefits of salt reduction. Population approaches are needed to reduce salt content of processed foods and restaurant meals.
authors.affiliation: aDepartment of Health and Nutrition, University of Human Arts and Sciences, Saitama, Japan bDepartment of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA cDepartment of Epidemiology and Biostatistics, School of Public Health, Imperial College of London, London, UK dDepartment of Public Health, Shiga University of Medical Science eCenter for Epidemiologic Research in Asia, Shiga University of Medical Science, Otsu fResearch Institute of Strategy for Prevention, Tokyo gDivision of Medical and Behavioral Subjects, Sapporo Medical University School of Health Science, Sapporo hDepartment of Public Health, Kanazawa Medical University, Kanazawa iDepartment of Hygiene and Preventive Medicine, Iwate Medical University, Morioka jDepartment of Food Science and Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka, Japan kState Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China lMRC-PHE Centre for Environment and Health, Imperial College London, London, UK.
authors.forename: Nagako
authors.initials: N
authors.lastname: Okuda
authors.forename: Jeremiah
authors.initials: J
authors.lastname: Stamler
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Brown
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ueshima
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Miura
authors.forename: Akira
authors.initials: A
authors.lastname: Okayama
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Saitoh
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Sakata
authors.forename: Katsushi
authors.initials: K
authors.lastname: Yoshita
authors.forename: Liancheng
authors.initials: L
authors.lastname: Zhao
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
mesh_terms: D000328:Adult; D000959:Antihypertensive Agents / Q000008:administration & dosage; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000517:prevention & control*; D002681:China / Q000453:epidemiology; D004039:Diet, Sodium-Restricted; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000517:prevention & control*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D017673:Sodium Chloride, Dietary / Q000652:urine*; D011795:Surveys and Questionnaires; D006113:United Kingdom / Q000453:epidemiology; D014481:United States / Q000453:epidemiology
chemical_list: D000959:Antihypertensive Agents; D017673:Sodium Chloride, Dietary