27th July 2021
Non-scientific threats to public health policies
1Cappuccio FP, 2He FJ, 2MacGregor GA, 3Campbell NRC
1Warwick Medical School, University of Warwick; 2Wolfson Institute of Preventive Medicine, Queen Mary’s, University of London; 3The University of Calgary, Alberta, Canada.
Purpose of Review
High dietary sodium is the leading dietary risk for death, estimated to cause 1.8 million deaths in 2019. There are uniform recommendations to reduce sodium consumption based on evidence that increased dietary sodium is responsible for approximately a third of the prevalence of hypertension, and meta-analyses of randomized controlled trials show that sodium reduction lowers blood pressure, cardiovascular disease, and total mortality.
The evidence supporting dietary sodium reduction is one of the strongest available for a dietary intervention given the difficulties in performing very large long-term interventions that alter diet, the ubiquitous addition of sodium to the food supply and salt (and other sodium-containing ingredients used at home), and the consensus that it is unethical to intervene to provide increased dietary sodium long term. Nevertheless, many view that reducing dietary sodium may be harmful, generating the perception that the beneficial effect of reducing dietary sodium is controversial. We provide experiential evidence relating to some sources of the controversy and propose potential solutions.
We have categorized the concerns regarding (1) use of inappropriate research methods and lack of rigor in research; (2) conflicts of interest with, or biases for, commercial organizations; (3) lack of public access to data supporting research; (4) scientific and professional conduct; (5) journal responsibility in publishing low-quality controversial research and inadequate review processes; (7) grants and research and ethics committee approvals for inappropriate study designs and methods; (8) health and scientific organization issues; and (9) lack of government oversight. These factors contribute to the controversy.
There is a failure to protect policies to reduce dietary sodium from non-scientific threats. For each category identified, we propose actions needed to support evidence-based dietary sodium public policies. Significant efforts need to be made to ensure the integrity of nutritional research and maintain public trust.