Study Links Potassium to Fewer Strokes in Women

September 24, 2014 Updated: September 24, 2014

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.

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).

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. 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.

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:

“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. 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.

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 cells) 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.

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.