By Marissa Lau, Pace University, 2022
Hypertension is a risk factor of multiple chronic diseases including cardiovascular disease, chronic kidney disease, dementia, and other diseases and conditions.1 This disease burdens 1.2 billion individuals worldwide making it a public health issue.2 Hypertension has several modifiable risk factors that can decrease the likelihood of developing the disease.1 Such risk factors include overweight or obese, diet consisting of high salt intake, sedentary lifestyle, and frequent alcohol use.1,3,4 In particular, low potassium intake in the diet can lead to the disease.1,3,4
The Role of Potassium on Blood Pressure
Regarding blood pressure, potassium and sodium play major roles in maintaining blood volume, hydro-electrolyte balance, and cell function via the renal system.3 More specifically, potassium can modify the effect of sodium on blood pressure in the renal system.3
When potassium intake is high, a negative sodium balance develops, resulting in increased sodium excretion, via urine, which is demonstrated through the downregulation of sodium chloride cotransporters.3 Through this mechanism, high potassium intake leads to high plasma potassium.3 The high plasma potassium maintains sufficient intracellular chloride, resulting in lower blood pressure.3
This mechanism is one biochemical pathway relating to blood pressure, but other studies have proposed additional renal and non-renal mechanisms that relate to hypertension and involve potassium and sodium mechanisms.3 The pathogenesis of this condition is complex, and more research is necessary to acquire a complete understanding of this topic.3
How Much Potassium Is Recommended?
Based on the 2020-2025 Dietary Guidelines for Americans, a daily goal of 2,000-3,400mg of potassium is recommended, depending on gender and age.5(p133) This amount is important as more than 80% of Americans have diets consisting of low intake of vegetables and fruits, which suggests that most Americans have low potassium intake.5(p30)
Knowing the guidelines’ potassium recommendation can be important, but hypertensive individuals can benefit from following the sodium-potassium ratio. The sodium-potassium ratio consists of low sodium and high potassium intake to lower blood pressure. Studies have even found that this ratio may be more significant for blood pressure maintenance, compared to the exact amount of potassium and sodium that an individual consumes.4
What Are Good Sources of Potassium?
Potassium supplementation may be used to increase potassium intake.3 Either potassium chloride or potassium citrate can be taken as one study has demonstrated that subjects that took either supplement had similar blood-pressure lowering effects.3 On the other hand, another study found a more significant decrease in blood pressure in subjects supplemented with potassium chloride, compared to those supplemented with potassium magnesium citrate and potassium citrate.3 Based on these studies, more research is necessary to determine the ideal form of potassium supplementation to provide optimal blood-pressure lowering effects.
Although studies have shown that potassium supplements are effective, it is not advisable as high intake of vitamins or minerals in a short period of time can lead to toxicity.4 Instead, diets consisting of high-potassium vegetables, fruits, and nuts is recommended.3,4 One study found that from the hypertensive individuals who increased their dietary intake of potassium, 81% of the individuals required less than half of the baseline medication and 38% did not need antihypertensive medication for blood pressure control, when compared to 29% and 9%, respectively, in the control group after 1 year of the follow-up.4
Following the sodium-potassium ratio, it is recommended to increase potassium consumption via fruits, vegetables, and nuts, in individuals who have moderate excess of sodium intake.3 For individuals with excessive salt intake, they can both reduce sodium intake and increase potassium intake.3 Diets should consist of fresh produce as frozen or canned produce contains lower potassium content.4 Processed foods should be limited as well since they are high in sodium and low in potassium.4 For individuals who prefer to follow a specific diet, the DASH diet or the Mediterranean diet is recommended as these diets emphasize the intake of vegetables, fruits, and nuts, and have shown to decrease risk of hypertension in hypertensive individuals.3,6
References:
1. High blood pressure (hypertension) - Symptoms and causes. Mayo Clinic. Accessed May 5, 2021. https://www.mayoclinic.org/diseases-conditions/high-blood-pressure/symptoms-causes/syc-20373410
2. Rossier BC, Bochud M, Devuyst O. The Hypertension Pandemic: An Evolutionary Perspective. Physiology. 2017;32(2):112-125. doi:10.1152/physiol.00026.2016
3. Burnier M. Should we eat more potassium to better control blood pressure in hypertension? Nephrology Dialysis Transplantation. 2019;34(2):184-193. doi:10.1093/ndt/gfx340
4. Samadian F, Dalili N, Jamalian A. Lifestyle Modifications to Prevent and Control Hypertension. Iranian Journal of Kidney Diseases. 2016;10(5):237-263.
5. U.S. Department of Agriculture, U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. Published online December 2020.
6. Magriplis E, Panagiotakos D, Kyrou I, et al. Presence of Hypertension Is Reduced by Mediterranean Diet Adherence in All Individuals with a More Pronounced Effect in the Obese: The Hellenic National Nutrition and Health Survey (HNNHS). Nutrients. 2020;12(3). doi:10.3390/nu12030853
