No change in 24-hour salt intake estimated from spot urine in Norwegian adults from 2006 to 2019. The population-based HUNT Study

Objective Monitoring time trends in salt consumption is important for evaluating the impact of salt reduction initiatives on public health outcomes. There has so far not been available data to indicate if salt consumption in Norway has changed during the previous decade. We aimed to assess whether average 24-hour salt intake estimated from spot urine samples in the adult population of mid-Norway changed from 2006-08 to 2017-19, and to describe variations by sex, age, and educational level. Design Repeated cross-sectional studies. Setting The population-based HUNT Study. Participants In each of two consecutive waves (HUNT3: 2006-08 and HUNT4: 2017-19), spot urine samples were collected from 500 men and women aged 25-64 years, in addition to 250 men and women aged 70-79 years in HUNT4. Based on spot urine concentrations of sodium, potassium and creatinine, age, sex, and body mass index, we estimated 24-hour sodium intake using the INTERSALT equation for the Northern European region. Results Mean (95% confidence interval (CI)) estimated 24-hour salt intakes in men were 11.1 (95% CI 10.8, 11.3) g in HUNT3 and 10.9 (95% CI 10.6, 11.1) g in HUNT4, p=0.25. Corresponding values in women were 7.7 (95% CI 7.5, 7.9) g and 7.7 (95% CI 7.5, 7.9) g, p=0.88. Mean estimated salt intake in HUNT4 decreased with increasing age in women, but not in men, and it did not differ significantly across educational level in either sex. Conclusions Estimated 24-hour salt intake in adult men and women in mid-Norway did not change from 2006-08 to 2017-19. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any external funding. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Regional Committee for Medical Research Ethics Mid-Norway gave ethical approval for this work. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The data that support the findings of this study are available upon application to the data owner but restrictions apply to the availability of these data, which were used under approval for the purpose of the current research project, and so are not publicly available.