By Dr. Mercola
Potassium is a mineral and an electrolyte that conducts electricity in your body. It plays an important role in heart function, skeletal health, digestion, and muscular function, and is essential for the proper function of all cells, tissues, and organs in your body.1
Despite the fact that potassium is available in many foods, especially fruits and vegetables, only 2 percent of US adults get the recommended daily amount of 4,700 milligrams (mg).2
Importantly, consuming enough potassium-rich food is also important because this nutrient helps offset the hypertensive effects of sodium. Imbalance in your sodium-potassium ratio can not only lead to hypertension (high blood pressure) but may also contribute to a number of other diseases, including heart disease and stroke.
Potassium-Rich Diet Lowers Stroke Risk in Women
Stroke is the number one cause of long-term disability and the fourth leading cause of death in the US.3 The most common type of stroke is called "ischemic stroke," which results from an obstruction in a blood vessel supplying blood to your brain. Once you suffer a stroke, the damage, should you survive it, can be absolutely devastating.
Thankfully, up to 80 percent of strokes are preventable, and positive lifestyle factors can make a major difference. One factor is your diet, and a potassium-rich diet, in particular.
New research found that women without hypertension who consumed the most potassium (nearly 3,200 mg/day) had a 21 percent reduced risk of stroke. Further, women who consumed the most potassium were 12 percent less likely to suffer from a stroke, and 12 percent less likely to die during the study period, than those who consumed the least.4 According to the study’s lead researcher:5
“Potassium may play a role in improving blood vessel function in our brains. This could allow better oxygenation of our brain tissue, and prevent tissue death that occurs from lack of oxygen to the brain… The effect of potassium consumption on reduced stroke risk could also be due to a better diet overall, though we did not investigate this in our study.”
As mentioned, your body needs potassium to maintain proper pH levels in your body fluids, and it also plays an integral role in regulating your blood pressure, which is a major risk factor for stroke if it becomes elevated and that potassium needs to come from food not from supplements or potassium salt.
Too Much Sodium and Too Little Potassium Is Risky for Your Heart
Excess sodium is often blamed for causing high blood pressure (which in turn elevates your stroke risk). However, potassium deficiency may be more responsible for hypertension than excess sodium.
One four-year long observational study (the Prospective Urban Rural Epidemiology (PURE) study), which included more than 100,000 people in 17 countries, found that while higher sodium levels correlate with an increased risk for high blood pressure, potassium helps offset sodium’s adverse effects.6, 7
In the study, those with the lowest risk for heart problems or death from any cause were consuming three to six grams of sodium a day—far more than US daily recommended limits. So while there is a relationship between sodium and blood pressure, it’s not a linear relationship, and potassium plays a role.
The authors proposed that instead of recommending aggressive sodium reduction across the board, it might be wiser to recommend high-quality diets rich in potassium instead. This, they surmised, might achieve greater public health benefits, including blood-pressure reduction. As noted by one of the researchers, Dr. Martin O'Donnell of McMaster University:8
“Potatoes, bananas, avocados, leafy greens, nuts, apricots, salmon, and mushrooms are high in potassium, and it's easier for people to add things to their diet than to take away something like salt.”
According to a 1985 article in The New England Journal of Medicine, titled "Paleolithic Nutrition,” our ancient ancestors got about 11,000 mg of potassium a day and about 700 mg of sodium.9 This equates to nearly 16 times more potassium than sodium.
Compare that to the Standard American Diet where daily potassium consumption averages about 2,500 mg (the RDA is 4,700 mg/day), along with 3,600 mg of sodium. This may also explain why high-sodium diets appear to affect some people but not others.
According to a 2011 federal study into sodium and potassium intake, those at greatest risk of cardiovascular disease were those who got a combination of too much sodium along with too little potassium. The research, published in the Archives of Internal Medicine, was one of the first and largest US studies to evaluate the relationship of salt, potassium, and heart disease deaths.
Tellingly, those who ate a lot of salt and very little potassium were more than twice as likely to die from a heart attack as those who ate about equal amounts of both nutrients.10
Increasing Potassium in Your Diet Is Like Decreasing Your Salt Intake (Without Really Cutting Back!)
A proper balance of potassium both inside and outside your cells is crucial for your body to function properly. As an electrolyte, potassium is a positive charged ion that must maintain a certain concentration (about 30 times higher inside than outside your cells11) in order to carry out its functions, which includes interacting with sodium to help control nerve impulse transmission, muscle contraction, and heart function.
Researchers have also determined that increasing average potassium intake to the recommended 4,700 mg a day would reduce systolic blood pressure by between 1.7 and 3.2 mm Hg on a population-wide scale. This decrease, they suggest, is similar to the reduction that would occur if Americans lowered their salt intake by 4 grams a day.12
I don’t advise consuming all the salt you want, of course, particularly if it’s processed salt. Salt is an essential nutrient required for blood pressure regulation, transportation of nutrients into and out of your cells, ion exchange, and brain-muscle communication. But all salts are not equal, in terms of their impact on your health.
Processed (table) salt is health harming, while natural unprocessed salt is not only healing, but in fact essential for many biological functions. It’s clear that many are consuming far too much processed table salt and not enough natural salt, largely by consuming too many processed foods. And, the easiest way to achieve an imbalance in your sodium-to-potassium ratio is by consuming a diet of processed foods, which are notoriously low in potassium while high in sodium.
The Best Way to Optimize Your Sodium-to-Potassium Ratio
If you eat a lot of processed foods and not many vegetables, there’s a good chance your sodium-to-potassium ratio is unbalanced. If you’re not sure, try a free app like MyFitnessPal, which allows you to enter the foods you eat and will calculate the ratio automatically. It's generally recommended that you consume five times more potassium than sodium, but most Americans get two times more sodium than potassium. If your ratio is out of balance…
- First, ditch all processed foods, which are very high in processed salt and low in potassium and other essential nutrients
- Eat a diet of whole, unprocessed foods, ideally organically and locally grown to ensure optimal nutrient content. This type of diet will naturally provide much larger amounts of potassium in relation to sodium
- When using added salt, use a natural salt. I believe Himalayan salt may be the most ideal, as it contains lower sodium and higher potassium levels compared to other salts
I do not recommend taking potassium supplements to correct a sodium-potassium imbalance. Instead, it is best to simply alter your diet and incorporate more potassium-rich whole foods. Green vegetable juicing is an excellent way to ensure you’re getting enough nutrients for optimal health, including about 300-400 mg of potassium per cup. Some additional rich sources of potassium are:
- Lima beans (955 mg/cup)
- Winter squash (896 mg/cup)
- Cooked spinach (839 mg/cup)
- Avocado (710 mg/cup)
Other potassium-rich fruits and vegetables include:
- Fruits: papayas, prunes, cantaloupe, and bananas. (But be careful of bananas as they are high in sugar and have half the potassium of an equivalent amount of green vegetables. It is a myth that you are getting loads of potassium from bananas; the potassium is twice as high in green vegetables)
- Vegetables: broccoli, Brussels sprouts, avocados, asparagus, and pumpkin
Tips for Lowering Your Stroke Risk
Your lifestyle has a direct impact on your stroke risk, and even small changes can make a difference. To lower your risk:
- Exercise will go a long way toward improving your insulin and leptin receptor signaling, thereby normalizing your blood pressure and reducing your stroke risk. I recommend a comprehensive program that includes Peak Fitness high-intensity interval exercises along with super slow strength training, Active Isolated Stretching, and core work. If you've had a stroke, exercise is also very important, as research shows it can significantly improve both your mental and physical recovery.13
- Processed meats: Certain preservatives, such as sodium nitrate and nitrite found in smoked and processed meats have been shown to damage your blood vessels, which could increase your risk of stroke. I recommend avoiding all forms of processed meats, opting instead for organic, grass-fed or pastured meats.
- Diet soda. Research presented at the American Stroke Association's International Stroke Conference in 2011 showed that drinking just one diet soda a day may increase your risk of stroke by 48 percent. Ideally, strive to eliminate all soda from your diet, as just one can of regular soda contains nearly twice my recommended daily allowance for fructose in order to maintain good health and prevent disease.
- Stress. The more stressed you are, the greater your risk of suffering a stroke. Research has found that for every notch lower a person scored on their well-being scale, their risk of stroke increased by 11 percent.14 Not surprisingly, the relationship between psychological distress and stroke was most pronounced when the stroke was fatal. My favorite overall tool to manage stress is EFT (Emotional Freedom Technique). Other common stress-reduction tools with a high success rate include prayer, meditation, laughter and yoga, for example. For more tips, see my article "10 Simple Steps to Help De-Stress."
- Vitamin D: According to research presented at the American Heart Association's (AHA) Annual Scientific Sessions in 2010, low levels of vitamin D—the essential nutrient obtained from sun exposure—doubles the risk of stroke in Caucasians.15 While many opt for vitamin D3 supplements to raise their vitamin D level, I strongly recommend optimizing your levels through appropriate sun exposure or by using a safe tanning bed (i.e. one with electronic ballasts rather than magnetic ballasts, to avoid unnecessary exposure to EMF fields). Ideally, you'll want to maintain your vitamin D level within the range of 50-70 ng/ml year-round.
- Hormone replacement therapy (HRT) and birth control pills. If you're on one of the hormonal birth control methods (whether it's the pill, patch, vaginal ring, or implant), it is important to understand that you are taking synthetic progesterone and synthetic estrogen -- something that is clearly not advantageous if you want to maintain optimal health. These contraceptives contain the same synthetic hormones as those used in hormone replacement therapy (HRT), which has well-documented risks, including an increased risk of blood clots, stroke, heart attack, and breast cancer.
- Statins. Statin drugs are frequently prescribed to reduce your risk of heart disease and stroke. However, research shows that these cholesterol-lowering drugs actually increase your risk of a second stroke if you've already had one. There are two reasons why this might happen: the drugs may either lower cholesterol too much, to the point that it increases your risk of brain bleeding, or they may affect clotting factors in your blood, increasing the bleeding risk.
- Grounding. Walking barefoot, aka "grounding," has a potent antioxidant effect that helps alleviate inflammation throughout your body. The human body appears to be finely tuned to "work" with the earth in the sense that there's a constant flow of energy between our bodies and the earth. When you put your feet on the ground, you absorb large amounts of negative electrons through the soles of your feet. Grounding helps thin your blood by improving its zeta potential. This gives each blood cell more negative charge which helps them repel each other to keep your blood thin and less likely to clot. This can significantly reduce your risk of stroke.