Healthy adults lower their cardiovascular risk by cutting daily sodium intake to at least 2,300 mg, and may lower it further by going as low as 1,500 mg, according to a new National Academies report.
Previously, 2,300 mg per day was considered the upper limit on intake in the Academies’ 2005 Dietary Reference Intakes. The update to those recommendations replaces the upper limit with a Chronic Disease Risk Reduction Intake.
The reason was evolving toxicological risk assessment, under which “the committee found there was insufficient evidence of risk of excess sodium or potassium intake within the healthy populations to establish a UL [upper limit] for either nutrient,” writing committee chair Virginia Stallings, MD, of Children’s Hospital of Philadelphia, in a preface to the report.
Still, the authors found moderate to strong evidence for both a causal relationship and a dose-response relationship between sodium and cardiovascular disease, hypertension, systolic blood pressure, and diastolic blood pressure.
Further reducing sodium intake within the 2,300 to 1,500 mg/d range for adults had randomized controlled trial evidence for blood pressure lowering but weak evidence of reduction in chronic disease risk.
The report “aligns with what the American Heart Association and other prominent public health organizations have been saying for years: we must eat less salt,” American Heart Association CEO Nancy Brown said in a statement.
The AHA likewise recommends no more than 2,300 mg a day, with an “ideal limit” of no more than 1,500 mg for most adults.
Because Americans average 3,400 mg of sodium daily, the National Academies’ report indicated little concern about insufficiency but still set adequate intake levels for various age groups. These levels ranged from 1,500 mg per day for people ages 14 years and older down to 110 mg daily for infants 6 months and younger, which represented a decrease for children ages 1 to 13 years, but an increase for adults ages 51 years and older.
The report also decreased the potassium adequate intake level for individuals ages 1 year and older. It is now 3,400 mg/day for most men and 2,600 mg/d for most women. Evidence was insufficient for any upper limit or a level at which chronic disease risk would be reduced.
In a preface to the report, Stallings drew attention to the role of the food industry in cutting sodium intake, noting that most salt in the diet isn’t added at home but in commercial preparation of food and drink ingredients and products.
“For the desired public health benefit of reduced sodium intake to be achieved, more attention must be paid by industry to reducing sodium in the food supply and by consumers who have the needed sodium content information and an understanding of how to make health-inspired food choices,” she wrote.
“We hope this report encourages the Food and Drug Administration to quickly release its voluntary sodium reduction targets for the food industry,” agreed Brown. “School leaders should also take note and reject the recent U.S. Department of Agriculture decision to weaken sodium standards in school meals and continue their commitment to serve students healthier foods. These two actions will drive the food industry to innovate and reformulate to use less sodium.”