Cutting back on salt is one of the oldest pieces of blood pressure advice, and one of the most debated. The evidence has become clearer in recent years: for most adults, eating less sodium lowers blood pressure within days, whether or not they already have hypertension or take medicine for it.

How much is too much

The CDC cites the federal recommendation of less than 2,300 mg of sodium a day for teens and adults, and estimates that Americans average more than 3,300 mg.

The 2025 AHA/ACC blood pressure guideline, from the American Heart Association, the American College of Cardiology and other groups, goes further. It calls under 2,300 mg a day the goal and an ideal limit of under 1,500 mg, for adults with or without high blood pressure. The guideline estimates that reaching these targets lowers systolic blood pressure by about 6 to 8 points in people with hypertension and about 1 to 4 points in people without it.

For people with chronic kidney disease, the 2024 KDIGO guideline suggests under 2 grams (2,000 mg) of sodium a day, with an exception for rare kidney conditions that waste sodium.

What the trials show

Two studies make the case well. The DASH-Sodium trial, published in 2001, fed participants carefully controlled diets. Lower sodium reduced blood pressure in people with and without hypertension, in men and women, across racial groups. Combining low sodium with the DASH eating pattern, rich in fruits, vegetables and low-fat dairy, lowered systolic pressure by 11.5 points in people with hypertension compared with a typical high-sodium American diet.

A 2023 crossover trial in JAMA tested 213 adults aged 50 to 75, including many already on blood pressure medicine. After just one week, a low-sodium diet lowered blood pressure in nearly three quarters of participants, and the average systolic difference between the high- and low-sodium groups was 8 points. The effect was similar whether or not people had hypertension or took medication.

Salt sensitivity varies from person to person, but these studies suggest most middle-aged and older adults respond. Our article on Mediterranean eating covers a pattern that pairs well with lower sodium.

Where the sodium comes from

The salt shaker is a small part of the problem. The CDC says most sodium comes from processed and restaurant foods, and lists deli meat sandwiches, pizza, soups, savory snacks, breads and rolls, cheese, poultry and mixed pasta and meat dishes among the top sources for adults. A few practical steps make the biggest difference:

  • Read the Nutrition Facts label. Compare similar products, since sodium can vary widely between brands of the same soup or bread.
  • Choose “no salt added” or low-sodium versions of canned vegetables, beans, broth and soup, as the CDC suggests.
  • Watch restaurant meals, which the CDC counts among the main sources. Ask for sauces and dressings on the side.
  • Cook more at home, using herbs, citrus, garlic, vinegar and pepper for flavor.

A note on salt substitutes

Salt substitutes replace part of the sodium with potassium. In the SSaSS trial of about 21,000 older adults in rural China with prior stroke or high blood pressure, a salt substitute that was 25 percent potassium chloride lowered rates of stroke, major heart events and death compared with regular salt. The 2025 AHA/ACC guideline now includes potassium-enriched salt substitutes among its lifestyle options.

The caution is important. The NIH Office of Dietary Supplements warns that if you have kidney disease or take certain medicines, such as ACE inhibitors or potassium-sparing diuretics, potassium-based salt substitutes could raise your potassium too high. A 2026 review of the guideline notes the same caution for people with severe CKD or reduced potassium excretion. Ask your doctor before switching. Our article on potassium that is too high or too low explains why.

When to talk with your doctor

If you have high blood pressure, heart failure or kidney disease, ask what sodium target is right for you; some people with heart failure have specific fluid and salt instructions. Checking your blood pressure at home before and after a few weeks of change is a good way to see your own response. Our guide to home blood pressure monitoring shows how. If a reading above 180/120 comes with chest pain, shortness of breath, back pain, numbness, weakness, a change in vision or difficulty speaking, the American Heart Association says to call 911.

Dr. Yana Shtern is board-certified in Internal Medicine and Nephrology, and salt, blood pressure and kidney function often come up together in her practice. You can read more on our hypertension page. If you would like help building a plan that fits how you eat, start with a complimentary meet and greet with Dr. Shtern.

This article is general information, not advice for your situation. Members can call the office with questions about their own care.