Human salt requirements
The National Academy of Sciences recommends that Americans consume a minimum of 500 mg/day of sodium to maintain good health. Individual needs, however, vary enormously based on their genetic make-up and the way they live their lives. While individual requirements range widely, most Americans have no trouble reaching their minimum requirements. Most consume "excess" sodium above and beyond that required for proper bodily function. The kidneys efficiently process this "excess" sodium in healthy people.
Experimental studies show that most humans tolerate a wide range of sodium intakes, from about 250 mg/day to over 30,000 mg/day. The actual range is much narrower. Americans consume about 3,500 mg/day of sodium; men more, women less. The very large percentage of the population consumes 1,150- 5,750 mg/day which is termed the "hygienic safety range" of sodium intake by renowned Swedish hypertension expert Dr. Björn Folkow. Chloride is also essential to good health. Every substance, including water, can be toxic in certain concentrations and amounts; this is not a significant concern for dietary salt.
Unless closely supervised by a medical practitioner, low-salt diets can create health problems for vulnerable populations, including
Since the elderly are more sensitive to the electrolytic balance in their bodies yet often have elevated blood pressure, and since the media carry endless stories about the dangers of hypertension, older persons may not appreciate the risks of reducing salt intakes which can create hyponatremia, low blood sodium levels. Hyponatremia is also known as “water intoxication;” in this regard, low blood sodium has been fatal to marathoners and football players who disregard proper hydration. The elderly more often become weak, dizzy or confused.
A generation ago, expectant mothers were advised to avoid salt to curb weight gain during pregnancy. Yet this is the very time of life when nutrition is vitally important. Low-salt diets by pregnant women increased stillborn births and low-birthweight infants and has been condemned by the American College of Obstetrics and Gynecology which has found “There is no clinical benefit in restricting sodium intake during pregnancy and there is the potential for harm.”