DEAR DR. BLONZ: I notice that potassium is a key nutrient that is found in several fruits and vegetables, and it is sometimes mentioned to help counter processed foods, which tend to have too much sodium. However, potassium is rarely promoted as a supplement in its own right -- why not? I also wonder why someone would need to be on a low-potassium diet, which one of my close friends has been prescribed. -- L.K., Oakland, California
DEAR L.K.: Potassium is an essential mineral nutrient that is one of the body's electrolytes and, along with sodium, regulates the water balance inside and outside of cells. Potassium holds its water inside of cells, while sodium holds its water outside of cells.
We ingest sodium by using salt as a seasoning and from many processed foods. Excess sodium in the diet can be a risk factor for high blood pressure, as it contributes to fluid pressure in the bloodstream. Potassium, an electrolyte involved in transmitting nerve signals (it keeps the heart beating), affects muscle tone and the body's acid-base balance, helps to move nutrients in and waste products out of our cells, and can help reduce blood pressure.
A healthful diet should be high in potassium-rich foods. Foods rich in potassium include bananas, prunes, potatoes (with the skin), beet greens and leafy green vegetables, tomatoes, raisins, apricots, legumes, citrus fruits and avocados.
But too much of anything is never good, and potassium is no exception. Certain health conditions and medications can upset the body's normal potassium balance. There may be situations where your health professional recommends a low-potassium diet. If this is the case, dietary potassium intake, especially high-potassium foods, might have to be monitored. If, on the other hand, your potassium is low, your physician might direct you to adjust your diet accordingly, or you may be prescribed a potassium supplement. (See b.link/w3x232fb for more on fluid and electrolyte balance.)
DEAR DR. BLONZ: My hair is thin and subject to frequent breakage. A friend suggested Norwegian kelp. Will this nutrient remedy my symptoms and stimulate hair growth? -- S. Tucson, Arizona
DEAR S.: Kelp, a vegetable that grows in the sea, is known primarily for its iodine content, but it also contains potassium, calcium, magnesium and sodium. Iodine is an essential mineral that plays a role in the manufacture of thyroid hormones -- the substances that help regulate the body's metabolism. (For more on iodine, see b.link/r9z97xkn.)
Dry, coarse, breaking hair and hair loss are among the symptoms of inadequate thyroid hormone (hypothyroidism), so perhaps that was the connection your friend mentioned. There are blood tests to determine if you have thyroid issues, so if this is a concern, discuss it with your health professional.
Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.