Few topics divide nutrition experts more. Here's what to know.
We're all about flavor—and salt can really boost it—so we got excited about new research hinting that current sodium guidelines could be unnecessarily strict. Current dietary guidelines for sodium recommend consuming no more than 2,300mg a day (that’s one teaspoon of salt) or 1,500mg if you have or are predisposed to high blood pressure.
Now, we need some sodium—about 500mg a day to keep our muscles and nervous systems healthy and to prevent dehydration. Get too much, though, and it pulls water into our blood vessels, expanding blood volume and raising blood pressure. Over the years, the strain of that extra pressure damages blood vessels, making them more likely to develop plaques that can cut off blood flow to the heart and brain. High sodium levels boost your likelihood of a heart attack or stroke and can spell trouble over the long haul even if you’re healthy today.
Stay low-sodium and high-flavor with these simple, expert-approved tips.
Lately, a few studies have questioned this wisdom, finding that moderate sodium intake (up to 5,000 mg a day) may not inflate blood pressure after all. However, “almost all of those studies struggle with design flaws,” says Elliott Antman, MD, of Harvard Medical School.
Consider a new study that tracked 2,632 healthy people for 16 years: Those who consumed less than 2,500 mg sodium daily had higher blood pressure than people who consumed more. Sounds encouraging, but the fine print reveals the findings were based on diets for six days at the study’s start; those initial diets were used to project sodium intake over 16 years. Because eating habits change over time, this isn’t the best way to size up salt intake.
Then there’s the question of how much reducing sodium really lowers blood pressure. Most of us eat roughly 3,400 mg sodium a day (75% of that intake is from processed foods). Trimming that to just below 2,300 mg scales back blood pressure by about four systolic and two diastolic points.
That’s hardly earth-shattering. But if you’re a salt junkie with high blood pressure, it’s a different story. “For people with hypertension, eating more than 6,000 mg of sodium a day tends to elevate blood pressure,” says Suzanne Oparil, MD, of the University of Alabama at Birmingham School of Medicine. So, “if you have high blood pressure, reducing sodium is part of the package, not a panacea,” says Oparil. “Eating a healthy diet, watching your weight, and exercising are more important.”