If you've been watching your sodium intake, is it time to pick the saltshaker back up? The Dietary Guidelines say that Americans should cap their sodium intake at 2,300 mg (about 1 teaspoon of salt) per day. But this may be too low, suggests a new study. Drawing on data from 130,000 people in 49 countries, researchers found that sodium intake below 3,000 mg per day (or 11/3 teaspoons of salt) was associated with increased risk of stroke, heart attack or cardiovascular disease—regardless of whether a person had high or healthy blood pressure.
Pass the Salt, Please
"Your body needs sodium or you'd die," says Andrew Mente, Ph.D., of McMaster University in Ontario, Canada, and lead study author. Because the mineral is key for many biological processes (it controls blood pressure and keeps nerves working properly), your body has built-in countermeasures to prevent your sodium level from dipping too low. When you get too little, your body releases hormones to conserve the sodium you do have. But these hormones promote inflammation in your arteries and other organs, which may account for Mente's findings.
This research echoes the findings of a 2014 scientific review published in the American Journal of Hypertension. That study found that daily sodium intake below 2,645 mg or above 4,954 mg was associated with an increased risk of mortality, regardless of other health conditions. Those researchers pointed out that most people put on low-sodium diets have higher starting blood pressure than the average person, so the beneficial effects of salt reduction on blood pressure may be overestimated.
Do You Need More Salt?
That said, most of us aren't at risk for going too low. The average American consumes more than 3,400 mg of sodium each day. And getting over 5,000 mg of sodium (a little over 2 teaspoons) daily is linked with high blood pressure.
Even still, Mente hopes his study will help shift guidelines away from being so restrictive. However, Linda Van Horn, Ph.D., R.D., of Northwestern's Feinberg School of Medicine, doesn't see a need to change the guidelines: "There are so few people in the U.S. who consume less than 2,300 mg sodium per day that concerns about inadequate intake are generally nonexistent."
While researchers continue to debate the ideal sodium range, most agree with this tip: watch where it comes from. Most sodium in the American diet comes from processed foods, such as bread, cold cuts and pizza.
Who Needs to Watch Their Salt Intake?
Even researchers who say that you can get too little sodium recognize the dangers of overdoing it and caution that certain populations are at greater risk for health complications from too much sodium. People with the following conditions or in these groups should keep an eye on their sodium intake:
• High blood pressure
• Kidney disease
• History of heart attack, stroke or cardiovascular disease
• African-Americans, who are uniquely genetically predisposed to sodium sensitivity
• People over the age of 50
However, Mente recommends that people in these groups cap sodium between 3,000 and 4,000 mg/day (1 1/3 to 1 3/4 teaspoons) while the American Heart Association is more restrictive, saying the ideal sodium limit is 1,500 mg (a little over 1/2 teaspoon). If you fall into any of these categories, talk to your doctor about how much sodium you should be getting.