Salt.... how bad is it?

Sodium is one of the primary electrolytes in the body. All four cationic electrolytes (sodium, potassium, magnesium, and calcium) are available in unrefined salt, as are other vital minerals needed for optimal bodily function. Too much or too little salt in the diet can lead to muscle cramps, dizziness, or even an electrolyte disturbance, which can cause severe, even fatal, neurological problems. Drinking too much water, with insufficient salt intake, puts a person at risk of water intoxication (hyponatremia). Salt is even sometimes used as a health aid, such as in treatment of dysautonomia.

People's risk for disease due to insufficient or excessive salt intake varies due to biochemical individuality. Some have asserted that while the risks of consuming too much salt are real, the risks have been exaggerated for most people, or that the studies done on the consumption of salt can be interpreted in many different ways.

Excess salt consumption has been linked to:

Exercise-induced asthma.On the other hand, another source counters, "…we still don't know whether salt contributes to asthma. If there is a link then it's very weak…".
Heartburn

Osteoporosis: One report shows that a high salt diet does reduce bone density in girls. Yet "While high salt intakes have been associated with detrimental effects on bone health, there are insufficient data to draw firm conclusions."

Gastric cancer (Stomach cancer) is associated with high levels of sodium, "but the evidence does not generally relate to foods typically consumed in the UK." However, in Japan, salt consumption is higher.

Hypertension (high blood pressure): "Since 1994, the evidence of an association between dietary salt intakes and blood pressure has increased. The data have been consistent in various study populations and across the age range in adults." Professor Dr. Diederick Grobbee claims that there is no evidence of a causal link between salt intake and mortality or cardiovascular events. One study found that low urinary sodium is associated with greater risk of myocardial infarction among treated hypertensive men

Left ventricular hypertrophy (cardiac enlargement): "Evidence suggests that high salt intake causes left ventricular hypertrophy, a strong risk factor for cardiovascular disease, independently of blood pressure effects." "…there is accumulating evidence that high salt intake predicts left ventricular hypertrophy." Excessive salt (sodium) intake, combined with an inadequate intake of water, can cause hypernatremia. It can exacerbate renal disease.

Edema (BE: oedema): A decrease in salt intake has been suggested to treat edema (fluid retention).

Duodenal ulcers and gastric ulcers : A large scale study by Nancy Cook et al shows that people with high-normal blood pressure who significantly reduced the amount of salt in their diet decreased their chances of developing cardiovascular disease by 25% over the following 10 to 15 years. Their risk of dying from cardiovascular disease decreased by 20%.

(Source: wikipedia.org)