Dear A.S.: The Dietary Guidelines for Americans recommend limiting sodium to less than 2,300 mg a day — or 1,500 mg if you’re age 51 or older, or if you are black, or if you have high blood pressure, diabetes or chronic kidney disease.
Keep in mind that these are upper limits, and less is usually best, especially if you’re sensitive to the effects of sodium. If you aren’t sure how much sodium your diet should include, talk to your doctor or dietitian.
If you’re like many people, you’re getting far more sodium than is recommended, and that could lead to serious health problems.
You probably aren’t even aware of just how much sodium is in your diet. Consider that a single teaspoon of table salt, which is a combination of sodium and chloride, has 2,325 milligrams (mg) of sodium. And it’s not just table salt you have to worry about. Many processed and prepared foods contain sodium.
Excess salt consumption raises your blood pressure. Salt would rapidly be fatal if the kidneys could not excrete it as fast as you eat it. But, the kidneys excrete salt faster at a higher blood pressure, and the ability of the kidneys to raise blood pressure provides powerful and life-saving protection against the accumulation of a dangerous backlog of salt. However, high blood pressure (also known as ‘hypertension’) unfortunately has a number of dangerous long-term health outcomes, and greatly increases the risk of both stroke and heart disease.
Taste buds are ‘flexible’ with respect to salt – they can adjust to both higher and lower salt intakes. By gradually reducing salt intake over a period of several months, the palate will alter to the extent that normal processed foods (i.e. those with added salt) will start to taste ‘too salty’.
People who are lucky enough to have normal blood pressure should adopt a low-salt diet to prevent hypertension developing later in life—lowering salt intake after a rise in blood pressure has occurred will not always have a reverse effect on blood pressure.