WMA Statement on Reducing Dietary Sodium Intake
Adopted by the 59th WMA General Assembly, Seoul, Korea, October 2008
and revised by the 70th WMA General Assembly, Tbilisi, Georgia, October 2019
PREAMBLE
Dietary table salt is an ionic compound comprising of sodium chloride, which is 40% sodium (Na+) and 60% chloride (Cl-). There is overwhelming evidence that excessive sodium intake is a risk factor for the development, or worsening of hypertension, which is one of the main cardiovascular risk factors. Hypertension may also be an independent risk factor for cardiovascular diseases as well as all-cause mortality. The effect of dietary sodium on blood pressure is influenced by various demographic factors such as age and ethnicity.
Salt intake is also a risk factor for gastric cancer [1].
The World Health Organization (WHO) recommends that average daily sodium consumption in adults (≥16 years of age) should be less than 2000 mg (5 g salt). For children (2–15 years of age), the adult intake limit of 2 g/day sodium should be adjusted downward based on the energy requirements of children relative to those of adults [2].
The majority of the world’s population consumes too much sodium – 3.95 (3.89–4.01) g/day, equivalent to table salt level of 10.06 (9.88–10.21) g/day. These consumption levels are far above the recommended limit [3].
The main source of sodium is dietary consumption, 90% of it in the form of salt [4], as added salt during cooking or eating, or in processed foods such as canned soups, condiments, commercial meals, baking soda, processed meats (such as ham, bacon, bologna), cheese, snacks, and instant noodles, among others. In higher-income countries sodium added during food processing can be as high as 75%-80% of total salt intake [5].
The Global Action Plan for the Prevention and Control of Non-Communicable Disease (NCDs) 2013-2020 is made up of 9 global targets, including a 30 % relative reduction in mean population intake of sodium. The WHO has created the S.H.A.K.E technical package to assist Member States with the development, implementation and monitoring of salt reduction strategies.
The WHO recognises that while salt reduction is recommended globally, there is concern that iodine deficiency disorders (IDD) may re-emerge as iodized salt is the main vehicle for dietary iodine intake through fortification. Therefore the WHO, in recognition of the importance of both sodium reduction and iodine fortification, urges that efforts of the two programs be coordinated [6].
Substantial overall benefits can result from even small reductions in the population’s blood pressure. Population-wide efforts to reduce dietary sodium intake are a cost-effective way to reduce overall hypertension levels and subsequent cardiovascular disease. Evidence shows that keeping sodium consumption within the reference level could prevent an estimated premature 2.5 million deaths each year globally [7].
RECOMMENDATIONS
1. WMA and its Constituent Members should:
a. Urge governments to recognise that salt consumption is a serious public health problem and prioritise prevention as an equitable, cost effective and lifesaving population-wide approach to address high sodium intake and the associated high burden of cardiovascular diseases.
b. Work in cooperation with national and international health organisations to educate consumers from childhood about the effects of excessive sodium intake on hypertension and cardiovascular disease, the benefits of long-term reductions in sodium intake, and about the dietary sources of salt/sodium and how these can be reduced.
c. Urge the governments and other stakeholders work together to achieve the targets set in the Global Action Plan for the Prevention and Control of NCDs 2013-2020.
d. Recognise the critical role of the food processing and food services industry in reducing dietary sodium, and support regulatory efforts involving mandatory targets in food processing, sodium content of foodstuffs, and clear labelling. Food reformulation efforts must target food products that are most commonly consumed in the population.
2. Constituent members of WMA should:
a. Encourage their governments strictly to enforce laws regulating the sodium content in processed foods.
b. Embrace a multi stakeholder approach in working towards reducing the consumption of excessive sodium by the population, including active promotion of physician awareness regarding the effects of excessive dietary sodium.
c. Recognise that sodium reduction and salt iodization programmes need to be compatible and support sodium reduction strategies that do not compromise dietary iodine content, or increase or worsen iodine deficiency disorders, especially in low income settings.
d. Contribute to making the public aware of the potential consequences of low iodine levels as a result of restricted iodized salt intake.
e. Encourage their members to contribute to scientific research on sodium reduction strategies.
f. Encourage the initiation of food labeling, media campaigns and population-wide policies such as mandatory reformulation to achieve larger reductions in population-wide salt consumption than individually focused interventions.
3. Individual physicians should:
Counsel patients about the major sources of sodium in their diets and how to reduce sodium intake, including reducing the amount of salt used in cooking at home, use of salt substitutes, and addressing any relevant local practices and beliefs that contribute to high sodium intake.
References:
[1] World Cancer Research Fund / American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. Washington DC: AICR, 2007.
[2] Guideline: Sodium intake for adults and children. Geneva, World Health Organization (WHO), 2012.
[3] Mozaffarian, Dariush, Fahimi, Saman, Singh, Gitanjali M., Micha, Renata, Khatibzadeh, Shahab, Engell, Rebecca E., Lim, Stephen, Danaei, Goodarz, Ezzati, Majid and Powles, John (2014) Global sodium consumption and death from cardiovascular causes. New England Journal of Medicine, 371 7: 624-634. doi:10.1056/NEJMoa1304127.
[4] J. He, N.R.C. Campbell, G.A. MacGregor. Reducing salt intake to prevent hypertension and cardiovascular disease. Rev. Panam. Salud Publica, 32 (4) (2012), pp. 293-300.
[5] World Health Organization Regional Office for Europe Mapping salt reduction initiatives in the WHO European Region (Web. 10 May 2014.) http://www.euro.who.int/__data/assets/pdf_file/0009/186462/Mapping-salt-reduction-initiatives-in-the-WHO-European-Region.pdf (2013).
[6] Salt reduction and iodine fortification strategies in public health. 2014. http://www.who.int/nutrition/publications/publichealth_saltreduc_iodine_fortification/en/.
[7] McLaren L, Sumar N, Barberio AM, Trieu K, Lorenzetti DL, Tarasuk V, Webster J, Campbell NRC.Population-level interventions in government jurisdictions for dietary sodium reduction. Cochrane Database of Systematic Reviews 2016, Issue 9. Art. No.: CD010166. doi: 10.1002/14651858.CD010166.pub2.