Sodium & Potassium: the Salts of Life in Mineral Nutrients, Alpha Nutrition Course Work

Life began in the sea and sea salts in water remain the internal milieu of all living cells. The main sea-water salt, sodium chloride, is the critical determinant of body fluids - held at 0.9% concentration in the human body, sodium intake must neither be deficient nor excessive for the body to function well.

North American diets tend to offer sodium levels 10-20 times higher than actual need (minimum of 1100 mg/day, adults). Average consumption of NaCl is 10-14.5 grams/day. Large salt surpluses are the result of high intake of commercially prepared food, and salt added at the table. Food usually contains enough sodium salts to supply our needs, and added salt tends to be surplus.

Salt and sugar are the two nutrients for which we have a specific appetite. The adaptation to high salt intake seems to involve cravings and compulsive eating of salted foods. The opposite adaptation occurs reduced salt intake - cravings for salt disappear, and heavily salted foods become unpalatable.

Sodium restraint is considered a primary strategy of reducing high blood pressure. The evidence that sodium restriction lowers blood pressure is less convincing now than previously thought. It is likely that only a subpopulation of hypertensives are sodium reactive. Increased intake of calcium and potassium may lower high blood pressure and extra potassium may protect against stroke-associated death.

To lower sodium intake, commercially prepared foods are avoided, and restraint is recommended in the use of table salt in cooking, and at the table. Table salt also supplies iodide; salt restriction may decrease iodide intake below RDA, and necessitate the addition of iodide to the supplement list.

The proper ratio of Sodium to Potassium is probably of 1 to 1. Most diets have sodium disproportion with the ratio tending toward sodium extreme excess. When you switch to low sodium foods, some added sodium salt may be required with potassium supplements to achieve optimal intake, especially if sodium and potassium loss occur from sweating or from vomiting and/or diarrhea.

Potassium chloride (KCl) is sold as a "salt substitute". Salt restriction KCl does not taste the same as regular salt, and should be used in cooking rather than added to food at the table. Some people acquire the potassium taste, and learn to enjoy KCl. Intentional potassium intakes of 1000-2000 mg per day are not unreasonable. Potassium supplements are also available in pill and liquid form. Tablets of potassium chloride (KCl) tend to irritate the small bowel, and may cause surface ulceration. KCl as the free salt or dissolved in water are the preferred potassium preparations. Manufacturers should add iodide as the potassium salt (KCl), to imitate regular iodized salt.