[Part Two in Our Series on the Importance of Sodium and Potassium In Our Diet]
High blood pressure, or hypertension as it’s referred to in medical circles, is the primary or contributing cause to over 400,000 deaths in the U.S. annually.1
The economic burden of hypertension and cardiovascular disease (CVD), which is a potential consequence of unchecked hypertension, is estimated at over 50 and 300 billion in the U.S., respectively.2 This makes reducing the health and economic burden of hypertension and heart disease a public health priority.
Reducing salt intake has been highlighted as one of the most cost-effective strategies for improving population-wide hypertension and CVD risk.3-5 In fact, a recent meta-analysis, summarizing multiple studies of the effects of reducing salt consumption on hypertension, found reduced blood pressure and cardiovascular events in individuals with high blood pressure.6
The habit of adding salt during cooking and the consumption of processed foods yields the majority of excess sodium intake. Sodium is added to many processed foods to preserve their shelf-life and increase palatability.
Almost 60 percent of Americans’ household food spending is used for ultra-processed food.7 And a growing majority fail to consume adequate vegetables and fruits. It’s easy to see how sodium intake can quickly skyrocket in the general population.
While behavior modification may help alter nutrition choices at an individual level, success in the general population has proven more difficult. Education and other awareness campaigns have not reduced salt intake, generally.8
Ultimately, population-based approaches are appealing because high blood pressure is on the rise most rapidly in low- and middle-income communities (and countries). Again, this is often due to the practice of adding salt during cooking and the high consumption of cheap, processed food stuffs.
If we can’t get people to reduce their salt intake, perhaps it’s time we adopt strategies to offset the intake of salt in our diets.
Salt substitutes and hypertension
Salt substitutes, such as NoSalt and Morton’s Salt Substitute, which is enriched with potassium, provide a novel and effective strategy for reducing blood pressure. In fact, research shows salt substitutes can reduce both systolic (SBP) and diastolic (DBP) blood pressure by approximately 5mmHg and 1.5mmHg, respectively.9-11
Encouragingly, the research suggests this effect is most pronounced in people struggling with hypertension.
Could simply swapping regular salt for a potassium-enriched salt make a significant difference?
Until recently, the effectiveness of population-wide interventions with salt substitutes had been inconclusive.
A recent study published in Nature examined the effect of replacing regular salt—or sodium chloride (NaCl)—in six villages in Peru, with a combination of 75-percent NaCl and 25-percent potassium chloride (KCl) on blood pressure and incidence of hypertension.
What did the scientists uncover? Study participants were 51 percent less likely to develop hypertension during the “intervention period” when taking the potassium-enriched salt, compared to the control period when consuming their normal table salt.12
To confirm the changes, an analysis of urine samples from the subjects showed there was an increase in potassium and “no change” in sodium status of participants.
Researchers also found an average reduction of 1.23mmHg in SBP and 0.72mmHg in DBP in the participants taking the salt substitute compared with controls—even after adjusting for sex, age, years of education, wealth index, and BMI measured at baseline.12
In short, there was a decrease in both systolic and diastolic blood pressure across the entire population, and the largest effect was seen in those with hypertension and in older individuals.
Do Small Improvements in Blood Pressure Really Impact Public Health?
Let’s investigate how much benefit one gains from reducing blood pressure by 1-2 mmHg. A recent meta-analysis of 61 observational studies of blood pressure and vascular disease in adults revealed for every 2mmHg decrease in SBP, stroke mortality and cardiovascular mortality decreased by 10 percent and 7 percent, respectively.
This benefit from lower blood pressure, brought about by reducing sodium in the diet, occurred not only in those with hypertension, but in normotensive individuals as well, down to a systolic blood pressure of 115mmHg.13
This suggests small reductions in blood pressure, at a population level, yield large public health gains.
How To Increase Potassium in Your Diet
These studies demonstrate that while there are clear benefits to reducing sodium in your diet, some of these same benefits can be accomplished by improving your sodium-to-potassium ratio.
Interestingly, increasing potassium intake yields lower blood pressure among individuals with hypertension and in individuals with high salt intake, regardless of whether they lower their sodium levels.15-18
Of course, most Americans don’t achieve the recommended intake and, therefore, do not consume adequate amounts of potassium to offset the effects of high sodium consumption. The high intake of processed foods (and subsequently sodium) creates the perfect storm for poor vascular health and increased risk of heart disease.
So how do you get more potassium? All fruits and vegetables naturally contain a greater ratio of potassium to sodium, unlike the modern hyper-palatable processed foods that line the shelves of convenience and grocery stores. If you’re consuming the recommended five to nine servings of vegetables and fruits per day, you’re likely achieving sufficient potassium levels to meet your needs.
Let’s look at which vegetables, leafy greens, and fruits provide the greatest quantities, so you can be sure to achieve the recommended 4,700mg of daily potassium for adults.
The following is a shortlist of potassium-rich food:14
The current guidelines for doctors treating patients with hypertension emphasize non-pharmacologic treatment, even in patients with low-risk, stage 1 hypertension.19
The use of potassium-enriched salt substitutes is a pragmatic approach for improving blood pressure across the population and, potentially, significantly reducing the incidence of hypertension as well.
Considering that the compliance of clients to anti-hypertensive medications is poor, and that antihypertensive medication is often unavailable or unaffordable in many low- and middle-income communities, practical solutions like potassium-enriched salt substitutes should be explored.20
Of course, education should also be provided on the importance of vegetable and fruit consumption for increasing potassium levels via the diet and reducing the intake of high sodium processed foods.
So, enjoy your next barbecue—with a potassium-enriched salt and a large serving of veggies!
Read More in Our Series on Sodium and Potassium in the Diet:
By Mark J. Smith, PhD
By Trevor Connor, M.S.
By Lorrie Cordain
- CDC, National Center for Health Statistics. Multiple Cause of Death 1999–2015. CDC WONDER online database. http://wonder.cdc.gov/mcd-icd10.html. December 2016. Accessed March 11, 2020.
- Constant AF, Geladari EV, Geladari CV. The economic burden of hypertension. Chapter 21. In: Andreadis EA, editor. Hypertension and Cardiovascular Disease. Switzerland: Springer International Publishing; 2016
- Wang, G. & Bowman, B. A. Recent economic evaluations of interventions to prevent cardiovascular disease by reducing sodium intake. Curr. Atheroscler. Rep. 15, 349 (2013).
- Salt Reduction: Fact Sheet (World Health Organization, 2016); https://www. who.int/news-room/fact-sheets/detail/salt-reduction
- Kontis V. et al. Three public health interventions could save 94 million lives in 25 years global impact assessment analysis. Circulation 140, 715–725 (2019).
- He, F. J., Li, J. & Macgregor, G. A. Effect of longer term modest salt reduction on blood pressure: Cochrane systematic review and meta-analysis of randomised trials. BMJ 346, f1325 (2013).
- Baraldi, L.G., Steele, E.M., et al. Consumption of ultra-processed foods and associated sociodemographic factors in the USA between 2007 and 2012: evidence from a nationally representative cross-sectional study. BMJ Open. 2018; (8)03:e020574.
- Trieu, K. et al. Review of behaviour change interventions to reduce population salt intake. Int. J. Behav. Nutr. Phys. Act. 14, 17 (2017).
- China Salt Substitute Study Collaborative Group. Salt substitution: a low-cost strategy for blood pressure control among rural Chinese. A randomized, controlled trial. J. Hypertens. 25, 2011–2018 (2007).
- Geleijnse, J. M., Witteman, J. C., Bak, A. A., den Breeijen, J. H. & Grobbee, D. E. Reduction in blood pressure with a low sodium, high potassium, high magnesium salt in older subjects with mild to moderate hypertension. BMJ 309, 436–440 (1994).
- Zhou, B. et al. Long-term effects of salt substitution on blood pressure in a rural north Chinese population. J. Hum. Hypertens. 27,427–433 (2013).
- Antonio Bernabe-Ortiz, A, Sal y Rosas, V, et al. Víctor G. Sal y Rosas, Ponce-Lucero, G. et al. Effect of salt substitution on community-wide blood pressure and hypertension incidence. Nat Med (2020).
- Lewington, S. et al. Age-specific relevance of usual blood pressure to vascular mortality: a meta-analysis of individual data for one million adults in 61 prospective studies. Lancet 360, 1903–1913 (2002).
- Health Link BC. High Potassium Eating. Online Database. Accessed March 11, 2020.
- Binia, A., Jaeger, J., Hu, Y., Singh, A. & Zimmermann, D. Daily potassium intake and sodium-to-potassium ratio in the reduction of blood pressure: a meta-analysis of randomized controlled trials. J. Hypertens. 33, 1509–1520 (2015).
- Mente, A. et al. Urinary sodium excretion, blood pressure, cardiovascular disease, and mortality: a community-level prospective epidemiological cohort study. Lancet 392, 496–506 (2018).
- Poorolajal, J. et al. Oral potassium supplementation for management of essential hypertension: a meta-analysis of randomized controlled trials. PLoS ONE 12, e0174967 (2017).
- Filippini, T., Violi, F., D’Amico, R. & Vinceti, M. The effect of potassium supplementation on blood pressure in hypertensive subjects: a systematic review and meta-analysis. Int. J. Cardiol. 230, 127–135 (2017).
- Whelton, P. K. et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J. Am. Coll. Cardiol. 71, 2199–2269 (2018).
- Attaei, M. W. et al. Availability and affordability of blood pressure-lowering medicines and the effect on blood pressure control in high-income, middle-income, and low-income countries: an analysis of the PURE study data. Lancet Public Health 2, e411–e419 (2017).