Salt Restrictions for Some May Be Better Than for All

By Joe Elia

Edited by André Sofair, MD, MPH, and William E. Chavey, MD, MS

Restricting sodium intake seems best suited to communities with the highest consumption levels, according to an 18-country study in The Lancet.

Researchers used urine samples from nearly 100,000 adults to estimate sodium and potassium intakes. Blood pressure was also measured, and cardiovascular events were tracked.

Mean sodium intake was 4.8 g per day, with Chinese communities having higher intakes (5.6 g). During a median follow-up of 8 years, a mean increase of 2.86 mm Hg in systolic pressure was noted for every 1-g increase in sodium intake above the overall average. There was a positive association between sodium intake and stroke, but only in communities with the highest sodium intake. Of note, the frequency of cardiovascular events showed an inverse association with sodium intakes in communities with the lowest intakes.

Higher potassium intakes were associated with lower rates of all cardiovascular events.

The authors suggest that targeting restrictions to communities with sodium intakes above 5 g/day would bring the most benefit. Commentators call the findings "exceedingly provocative."