Salt And Healthy

Salt is essential not only to life, but to good health. It's always been that way. The body's salt/water ratio is critical to metabolism. Human blood contains 0.9% salt (sodium chloride) -- the same concentration as found in United States Pharmacopeia (USP) sodium chloride irrigant commonly used to cleanse wounds. Salt maintains the electrolyte balance inside and outside of cells. Routine physical examinations measure blood sodium for clues to personal health. Most of our salt comes from foods, some from water.

Inadequate salt can be problematic. Doctors often recommend replacing water and salt lost in exercise [see advice on maintaining hydration for weekend athletes bodybuilders, professional athletes and outdoor athletes such as marathon runners and ultraendurance athletes and when working outside. Older people have special concerns to consume sufficient salt. Wilderness hikers know the importance of salt tablets to combat hyperthermia. Oral rehydration involves replacing both water and salt. Oral Rehydration Therapy (ORT) has been termed, by the British Medical Journal "the most important medical advance this (20th) century." Expectant mothers are advised to get enough salt . Increased salt intakes have been used successfully to combat Chronic Fatigue Syndrome. The unique microclimate of salt mines is a popular way to treat asthma, particularly in Eastern Europe .

Dramatic deficiencies (e.g. "salt starvation" in India) or "excessive" sodium intakes have been associated with other conditions and diseases, such as hypertension and stomach cancer. The long-accepted view that the body maintains a constant amount of sodium has been questioned recently by two separate teams of German scientists who postulate "osmotically inactive sodium storage" beyond the balance maintained by the kidney.

Testing the salinity of perspiration is a good test for cystic fibrosis; scientists suspect that cystic fibrosis is caused by a deformed protein that prevents chloride outside cells from attracting needed moisture. (And, of course, we cannot forget that iodized salt is the choice of public health professionals to combat iodine deficiency, has been fortified to battle other diseases like lymphatic filarisis and is considered "the first antibiotic").

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. 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.

For 4,000 years, we have known that salt intakes can affect blood pressure through signals to the muscles of blood vessels trying to maintain blood pressure within a proper range. We know that a minority of the population can lower blood pressure by restricting dietary salt. And we know that elevated blood pressure, “hypertension,” is a well-documented marker or “risk factor” for cardiovascular events like heart attacks and strokes, a “silent killer.” Reducing blood pressure can reduce the risk of a heart attack or stroke – depending on how it’s done.

Some have suggested that since salt intakes are related to blood pressure, and since cardiovascular risks are also related to blood pressure, that, surely, salt intake levels are related to cardiovascular risk. This is the “salt hypothesis” or “sodium hypothesis.” Data are needed to confirm or reject hypotheses.

Blood pressure is a sign. When it goes up (or down) it indicates an underlying health concern. Changes result from many variables, often still poorly-understood. High blood pressure is treated with pharmaceuticals and with lifestyle interventions such as diet and exercise. The anti-hypertensive drugs are all approved by regulatory authorities such as the U.S. Food and Drug Administration. To be approved, these drugs must prove they work to lower blood pressure. Whether they also work to lower the incidence of heart attacks and strokes has not been the test to gain approval (it would take too long to develop new drugs), but the National Heart, Lung and Blood Institute has invested heavily in such “health outcomes” studies.