Nutrition Notes: Potassium protection

Although potassium is a mineral found in almost every food group, poor eating habits can leave you short of this nutrient, which serves many vital functions in the body.

To help control blood pressure, the National High Blood Pressure Education Program strongly suggests getting enough potassium. In fact, the famous DASH diet, which is low in sodium and saturated fat and high in potassium and calcium, has proven successful at lowering blood pressure.

Several large studies also link a higher level of potassium in the diet with a lower risk of stroke. Potassium’s impact on blood pressure could be the link, since high blood pressure raises the risk of stroke. But potassium may also help prevent harmful changes in the walls of blood vessels going to or inside of the brain.

Adequate levels of potassium also decrease the amount of calcium excreted in urine, lowering the risk for calcium-based kidney stones. It also protects bones from osteoporosis.

For all the benefits of potassium, there are a few precautions. As long as our kidneys work properly, any excess amount of potassium is excreted in urine. But if the kidneys are compromised, high levels of potassium from supplements or excess use of salt substitutes can accumulate and cause abnormal heart rhythms. Certain medications also limit the body’s ability to eliminate excess potassium.

Our early ancestors probably consumed 6,000 to 10,000 mg of potassium daily. Surveys now place average adult consumption between 2,100 and 3,200 mg. Many adults consume considerably less. Although some researchers suggest 2,500 to 3,500 mg is a good target for adults to aim for, the latest federal recommendations assign greater health benefits to 4,700 mg.

Food processing often reduces the amount of potassium people get. Refined white flour is lower in potassium than whole wheat flour. Vegetables boiled in large amounts of water lose potassium during cooking. Snacks and baked goods high in fat and sugar, which play a large role in some diets, are generally very low in potassium.

Ideal sources of potassium include vegetables, fruits and fish. You can build your potassium intake, as well as help lower your cancer risk, by striving to eat the eight or more servings of vegetables and fruits each day recommended by the DASH diet to reduce blood pressure.

“Nutrition Notes” is provided as a public service by the American Institute for Cancer Research, 1759 R Street, NW, Washington, DC 20009