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Sodium and potassium are important micronutrients for human health. However, health issues arise when sodium intake exceeds potassium. Improving the sodium-to-potassium ratio may be a helpful strategy for overall health.  

A large percentage of the population consumes too much sodium and too little potassium, leading to a high sodium-to-potassium ratio. This trend begins in childhood. One 2017 study looking at school-aged children in the U.S. reported that 90% of children exceeded the upper limit of sodium. According to a 2024 study, children 10 to 12 years old in Poland consumed the most sodium compared to younger and older age groups.  

Another study noted that 79% of preschool children in the U.S. between 1 and 3 years of age and 87% of children 4 to 5 years of age exceeded the upper limit of sodium. The same study found that only 5% of children 1 to 3 years of age and 0.4% of children 4 to 5 years of age met the adequate intake level of potassium, although 97% of infants did. Based on data from the 2011 – 2012 NHANES study, only 1/10 of the American population had a sodium-to-potassium ratio in line with the World Health Organization (WHO) guidelines, which is less than or equal to 1. 

Cardiovascular Health 

Many concerns regarding high sodium intakes stem from the impacts on blood pressure. A healthy sodium-to-potassium ratio can help mitigate some of this risk. An older systematic review reported that the sodium-to-potassium ratio was more strongly associated with blood pressure levels than either mineral, at least in hypertensive adults. More recent evidence supports this finding, suggesting that a heart-healthy diet emphasizes a healthy balance between sodium and potassium.  

In an older study looking at sodium levels and sodium-to-potassium ratios in prehypertensive patients, both high sodium levels and high sodium-to-potassium ratios were associated with an increased risk of hypertension and cardiovascular disease. Using 24-hour urine collection, the researchers measured sodium and potassium excretion levels. They also took blood samples to test for inflammatory cytokine levels. The participants were followed for 29 months, plus or minus six months. Ultimately, researchers determined that increased sodium was associated with an increased sodium-to-potassium ratio, the prevalence of diabetes mellitus, BMI, triglycerides, C-reactive protein (an inflammatory marker), severe coronary artery stenosis, and IL-6 expression.  

Significant correlations between sodium and potassium intake, their ratio, and blood pressure were described in another study. For every increase of one standard deviation (SD), or 25.6 mmol, of sodium intake, there was an associated increase of 1.39 mmHg systolic blood pressure. For potassium, a 1-SD (3.4 mmol) increase in potassium intake correlated with a decrease of 1.42 mmHg systolic blood pressure. Any 1-unit increase in the sodium-to-potassium ratio led to an increase of 0.97 mmHg in systolic blood pressure. There was a similar trend with diastolic blood pressure: 1-SD increase of sodium led to a 0.94 mmHg increase in diastolic blood pressure. For potassium, an increase of 1-SD decreased diastolic blood pressure by 0.91 mmHg, and for a 1-unit increase in the ratio, there was an increase of 0.65 mmHg of diastolic blood pressure. Low potassium intake and a high sodium-to-potassium ratio are significantly associated with an increased risk of hypertension. 

A similar association exists in adolescents. Data from the 1999 to 2012 NHANES study revealed that young adolescents 12 to 14 years old had high levels of sodium consumption and low levels of potassium, both risk factors for high systolic blood pressure. A high sodium-to-potassium ratio was also associated with a higher risk of high systolic blood pressure. This study defined a high ratio as at or above 2.5. Even when adjusting for multiple variables, the association between the ratio and high blood pressure remained, more so than the association with the individual minerals. In this study, only 27.2% of the 12 to 14-year-olds consumed the recommended intake of sodium, and only 4.2% met the recommendations for potassium. Similarly, a newer study confirmed these findings, showing that as the urinary sodium-to-potassium ratio increased, so did blood pressure. Results were also consistent with increased daily salt consumption. Moreover, individuals with a high sodium-to-potassium ratio and high salt intake had significantly elevated blood pressure (P<0.001) compared to individuals just consuming high salt (P=0.017), suggesting that the ratio is an important factor for blood pressure beyond salt intake alone.  

A high sodium-to-potassium ratio is also associated with an increased risk of stroke. In one older study looking at adult New Yorkers, the hazard ratio in those with a higher sodium-to-potassium ratio was 1.6 for stroke, including ischemic stroke. Among the over 2,500 participants, the mean sodium-to-potassium ratio was 1.22. A newer study assessing the association of high sodium-to-potassium with incident cardiovascular events (e.g., stroke, myocardial infarction, coronary revascularization) found that consuming more sodium and less potassium increased the risk of cardiovascular incidents in a dose-dependent relationship.  

Additional Health Factors 

All-Cause Mortality 

High sodium intake, coupled with low potassium intake, is associated with all-cause mortality. In one study analyzing the data of 13,855 participants from NHANES 2003 – 2018, all-cause mortality increased when sodium and potassium levels were high and low, respectively. Interestingly, researchers reported that sodium intake below 3.1 g/day was negatively correlated with all-cause mortality. However, intake exceeding 3.1 g/day was not associated with all-cause mortality for non-elderly individuals. Similarly, a daily potassium intake above 3.5 g/day was negatively associated with all-cause mortality. Mortality risk is minimized at these levels of intake. However, findings for individuals 60-80 years of age suggest a U-shaped relationship, indicating that mortality risk increases at both low and high sodium intake levels. The inflection point for this group is 3.6 g of sodium/day. These results suggest the importance of consuming a balanced diet of moderate sodium and high potassium for overall health.    

Bone Health 

High sodium intake is also associated with a higher excretion of calcium in the urine, which could impact bone health, among other health factors. Higher potassium intake helps improve calcium and phosphorus, reduces bone reabsorption, and increases bone formation rate. An older study assessed the impacts of a high sodium-to-potassium ratio on bone mineral density (BMD) in middle-aged adults. Researchers collected data through food frequency questionnaires and urinary samples to determine the sodium-to-potassium ratio and performed BMD scans. They described that in women there was a gradual decrease in the BMD, except in the femur neck, when the sodium to potassium ratio increased, although it was not the same for men. This result was more pronounced in those who did not engage in much physical activity.  

Other studies have found a correlation between low sodium intake and increased risk of bone fracture. One study evaluated the risk of fractures in adult trauma patients with and without hyponatremia and hypokalemia. Patients with hyponatremia had an increased risk of thoracic vertebral, pelvic, and femoral fractures, while hypokalemic patients did not experience increased fracture risks. These results corroborate the finding that balanced sodium and potassium in the diet are more important recommendations than simply reducing sodium intake.  

Metabolic Health 

A high sodium-to-potassium level also increases the risk of obesity. A cross-sectional study looked at school-aged children between the ages of 7-12 and evaluated sodium intake to body mass index (BMI) and % body fat (% BF). A significant correlation existed between high urinary sodium excretion and high % BF. Evaluating the long-term effects of excessive salt consumption on type 2 diabetes incidence, researchers found that regular consumption of excessive salt increased the risk of developing type 2 diabetes, regardless of genetic susceptibility. Because increased % BF and type 2 diabetes are implicated in obesity, managing salt consumption in the diet may help prevent obesity and obesity-related diseases.  

Pregnancy 

A study on healthy pregnant women found that a high sodium-to-potassium ratio was an indicator of poor diet quality and risk of micronutrient deficiency during pregnancy. Sodium excess may predispose pregnant women to greater gestational weight gain, which is associated with macrosomia, preterm birth, and cesarean delivery. 

Gene Variants That Affect Sodium-Susceptibility  

Some studies show that certain individuals are more susceptible to the effects of sodium than others. For example, factors historically associated with increased susceptibility include female sex, age, race, and body weight. However, recent studies have focused more on the angiotensin-aldosterone, sympathetic nervous, and immune systems and their involvement in the pathogenesis of hypertension in salt-sensitive individuals.  

In women, sodium sensitivity increases due to several physiologic factors post-menopause, including vascular dysfunction, changes in adrenal responses, higher expression of the aldosterone-endothelial cell mineralocorticoid receptor, and increased activation of the endothelial epithelial sodium channel. Similarly, African Americans may be more susceptible due to the increased activation of the endothelial epithelial sodium channel. However, issues with fatty acid oxidation and inflammation may also be relevant in understanding sodium susceptibility.  

An older study from 1996 suggested that salt sensitivity is heritable in African Americans via a heritable hypertensive phenotype. However, newer data suggests that racial disparities in salt sensitivity disappear when potassium intake is increased.  

Researchers evaluated the effect of weight loss on salt-sensitive (SS) or salt-resistant (SR) overweight/obese patients. Interestingly, they found different observations in the SS and SR phenotypes after a year of intervention with diet, exercise, and metformin. SS patients experienced reduced blood pressure, albuminuria, and salt sensitivity. Additionally, obese SS patients had comparable blood pressure-lowering effects from salt restriction and weight loss. SR patients did not experience reduced blood pressure or albuminuria. Researchers concluded that blood pressure changes depend on the phenotype (i.e., SS or SR).  

While hypertension in salt-sensitive individuals is a growing area of research, some gene variants have been found to contribute to its pathogenesis. For example, gene variants independently associated with salt-sensitive hypertension include those involved in aldosterone management (B2AR, ESR2, and SGK1) and vascular dilation (AGT). Individuals who carry “risk alleles” from gene variant combinations B2AR/SGK1 and ESR2/SGK1 were more likely to have greater salt sensitivity. These data may be used to identify proper medication treatment for salt-sensitive individuals with specific gene variant combinations.  

Net Dietary Acid Load: Connection with Sodium & Potassium 

The potential of hydrogen (pH) balance is essential for normal bodily functions, and each body area has a different pH requirement. For example, the stomach has a very low pH (1.5 – 2.0) as it contains hydrochloric acid to break down food. The blood pH should be close to neutral, with the normal range between 7.35 and 7.45. When blood pH drops lower than this, it becomes acidic and might lead to a condition known as acidosis. When it becomes higher, the blood becomes alkaline. 

Many studies have connected the modern Western diet with a higher risk of developing mild metabolic acidosis, which causes blood pH imbalance. Individuals who eat a Western diet may have a high dietary acid load due to eating excessive animal proteins and processed foods. Metabolic acidosis develops when the body enacts compensatory processes to restore the acid/base balance, but the need outweighs the ability to create sufficient bicarbonate acid for buffering. Researchers have linked mild metabolic acidosis to a higher risk of metabolic syndrome, diabetes, insulin resistance, chronic kidney disease, multiple sclerosis, and hypertension. 

Dietary acid load is relevant in the discussion of sodium and potassium. A food’s acidogenic potential is often calculated using potential renal acid load (PRAL) and net endogenous acid production (NEAP). PRAL looks at the nutrient ionic balance; the absorption rates of protein, potassium, phosphorous, magnesium, and calcium; and the sulfate production from metabolized protein. A potentially acid-forming food is positive, and an alkaline-forming food is considered negative. NEAP considers the intake of potassium and protein to determine the potential for forming endogenous acid. Foods rich in potassium and magnesium, which are generally plant-based foods, help reduce the net acid dietary acid load to balance the acid potential of animal protein foods and potentially improve metabolic acidosis. Thus, potassium levels greatly impact the risk of metabolic acidosis by providing a buffer to maintain the acid/base balance. 

Sodium impacts the acid balance oppositely. It reduces the ratio of sodium to chloride, which in turn also reduces the capacity of the body to properly buffer the increased acid load. One older study found that IV infusions of sodium chloride induced metabolic acidosis. Another study reported that oral ingestion of sodium chloride in an alkaline diet led to an increase in the ratio of plasma chloride to bicarbonate, which is a marker for acid/base balance. The additional sodium chloride levels also led to a reduction in the set point at which the body regulates the bicarbonate levels independent of any change to the NEAP. 

Therefore, a high intake of potassium and a low intake of sodium, leading to a more optimal sodium-to-potassium ratio, also helps to reduce the risk of metabolic acidosis and associated diseases. 

The Role of “Iodized” Salt in Sodium and Potassium Status 

Iodine is an essential trace mineral required by the body. Unlike sodium and potassium, natural iodine sources are limited. Food sources include seaweed, some dairy products, seafood, and fortified foods. As a result, many manufacturers around the globe add iodine to table salt in the form of potassium iodide and cuprous iodide.  

One study assessed iodine intake sufficiency in Italian adults and found that iodized table salt accounts for 43% of iodine intake. However, even in countries where salt consumption is high and iodized salt is a known source of iodine, iodine levels remain inadequate. Because health initiatives aiming to prevent cardiovascular diseases often suggest reducing table salt and processed foods, iodine consumption may remain insufficient. It’s possible that, by decreasing fortified sources of iodine, individuals are inadvertently consuming less iodine and contributing to poorer health outcomes.  

Recently, potassium-enriched salt has become an alternative to table salt. The Salt Substitute and Stroke Study (SSaSS) suggested switching from table salt to potassium-enriched salt to prevent diseases related to high sodium consumption. After five years, participants consuming the potassium-enriched salt substitute experienced lower blood pressure, reduced risk of stroke, fewer cardiovascular events, and less premature death. Like iodized salt, iodine can be added to potassium-enriched salt, supporting recommendations to consume more potassium and iodine while reducing sodium.  

Supplementing: What to Know 

Supplementing with sodium and potassium is generally not recommended unless individuals have a particular health issue. Most people consume sufficient sodium in their diet. However, some individuals may benefit from potassium supplementation, especially if at risk of hypokalemia. For example, a systematic review and meta-analysis found that potassium supplements in hypertensive patients effectively lowered blood pressure. Potassium supplementation was especially beneficial in individuals who were consuming high amounts of sodium and low amounts of potassium and not taking antihypertensive medications. Another study found that potassium supplementation coupled with sodium reduction lowered blood pressure. However, this study determined that potassium supplementation was more likely to support reduced blood pressure than lower sodium in the diet. These studies suggest that improving one’s sodium-to-potassium ratio is advantageous for health outcomes. 

Individuals taking certain medications, including potassium-sparing diuretics and renin-angiotensin-aldosterone system (RAAS) inhibitors, should be especially mindful of their potassium intake due to the increased risk of hyperkalemia. This is also true in individuals with chronic kidney disease, diabetes, and heart failure. People with these health complications, especially if they are taking medications, should not consume potassium supplements, unless under the guidance of a trained medical professional.  

What to Do 

Although there is no universal standard for an optimal sodium-to-potassium ratio set by major organizations such as WHO or the Institute of Medicine, the general recommendation is to increase potassium and decrease sodium intake. Based on WHO adult recommendations of less than 2 g/day of sodium (or ~5g/day of salt) and at least 3.510 g/day of potassium, that ratio would become 0.57:1 (sodium to potassium). WHO does state that a general guideline for the ratio should be close to 1:1. 

When meal planning to create an ideal ratio, individuals want to aim for two to three times the amount of potassium as sodium to keep the ratio within this range. However, at a minimum, the ratio should be one-to-one.  

As always, it is best to start with a food-first approach. With these particular minerals, individuals may not need to supplement, as it is very easy to obtain sufficient quantities from foods. Following a healthy, colorful diet with little to no processed foods will ensure these nutrient needs are met.  

Final Thoughts 

A balanced sodium-to-potassium is possible. Taking small, measurable actions in the daily diet can help support this goal. Minimizing or avoiding high-salt meals and processed foods while increasing fruit and vegetable consumption are easy places to start.  

Suggestions: 

• Add more colorful whole foods to meals, especially meals that don’t typically include plant foods. 

• Add legumes to a meal in place of simple carbohydrates.  

• Cook at home for most meals to control how much salt is added to foods.  

• Ask for a side salad or include a vegetable when eating out at restaurants. 

• Avoid boiling foods as this may reduce potassium content, especially if boiling for longer periods.  

Before beginning nutrition and lifestyle practices to improve sodium-to-potassium ratios, talk to a doctor, nutritionist, dietician, or another healthcare team member for personal options based on individual circumstances.