Hypertension affects about half of all Americans, and is associated with an increased risk of heart attack and stroke. It also typically goes hand in hand with other features of metabolic syndrome such as obesity, insulin resistance, and fatty liver as well—though not in every case.

Why is hypertension so prevalent? Probably for the same reason that metabolic syndrome is so prevalent: a standard American diet of highly processed foods, chemicals, sugar, and trans fats, low in whole foods and particularly in fruits and veggies. In the case of metabolic syndrome, it’s the trans fats and the sugar (or even worse, high fructose corn syrup) that is to blame. In the case of hypertension, the problem is at least in part the high sodium from processed foods, and low potassium to too few fruits and vegetables.

Why Potassium Matters

Potassium exerts a positive effect upon the walls of the blood vessels, relaxing them and thus lowering systolic blood pressure (the top number). It also causes the kidneys to release sodium, and water follows sodium, thus lowering blood volume as well. (More on this below.)

Perhaps because of this, increased potassium was associated with a 24% decrease in stroke risk. It may also reduce overall risk of cardiovascular disease.

Signs of potassium deficiency include muscle weakness and fatigue, muscle cramping, nausea, poor appetite, and arrhythmias.

The Sodium to Potassium Ratio

Most people are aware that lowering sodium can lower blood pressure. This is because high sodium leads to fluid retention, in blood vessels as well as other tissues. But since sodium and potassium are on a see-saw, increased potassium can offset the effects of higher levels of sodium, due to loss of sodium through urine.

In fact, the sodium to potassium ratio is more important than either value alone in terms of regulating blood pressure.

Potassium intake should be around 3.5 grams per day for blood pressure control, from whole food sources primarily.

How to Increase Your Potassium

Potassium is especially high in avocados, bananas, potatoes, apricots, and prunes. Other good sources include cantaloupe, honeydew, grapefruit, oranges, leafy greens, peas, beans, mushrooms, and tomatoes.

Most produce, in other words, is a good source of potassium.

If you’re really concerned about increasing potassium, you can swap your table salt (NaCl) for potassium salt (KCl) for a similar flavor.

Possible Caveats

While supplements do exist for potassium, it’s a good idea to add it only with medical supervision, as potassium levels should be kept in a fairly narrow range. Too much is particularly problematic for those with kidney disease, but excessive levels of potassium can also lead to nausea, vomiting, diarrhea, arrhythmias, numbness and tingling.

Those who are taking ACE inhibitors or ARB medications for blood pressure, as well as certain diuretics, may also be at risk for too much potassium and would need to be careful with supplementation.

Potassium and Your Blood Pressure