A low sodium diet is a diet that includes no more than 1,500 to 2,400 mg of sodium per day.
The human minimum requirement for sodium in the diet is about 500 mg per day, which is typically less than one-sixth as much as many diets “seasoned to taste”. For certain people with salt-sensitive blood pressure or diseases such as Ménière’s disease, this extra intake may cause a negative effect on health.
A low sodium diet has a useful effect to reduce blood pressure, both in people with hypertension and in people with normal blood pressure. Taken together, a low salt diet (median of approximately 4.4 g/day – approx 1800 mg sodium) in hypertensive people resulted in a decrease in systolic blood pressure by 4.2 mmHg, and in diastolic blood pressure by 2.1 mmHg.
Advising people to eat a low salt diet, however, is of unclear effect in either hypertensive or normal tensive people. In 2012, the British Journal Heart published an article claiming that a low salt diet appears to increase the risk of death in those with congestive heart failure, but the article was retracted in 2013. The article was retracted by the journal when it was found that two of the studies cited contained duplicate data that could not be verified.
A doctor might prescribe a low sodium diet for patients with diabetes insipidus.