The national guidelines recommend that the general population should have a daily sodium intake of less than 2.3 grams, while people with diabetes, kidney disorders or cardiovascular disease should only have less than 1.5 grams. Yet a Prospective Urban Rural Epidemiology (PURE) study claims these national guidelines set on daily salt intake may bring more harm than good.

The PURE study engaged over a thousand adults, who greatly vary in geographic, demographic and socioeconomic makeup, from general populations of 17 countries. Taken from them for the study were morning urine samples.

Based on sodium excretions, 90 percent showed either high or moderate salt intake daily. By high intake, the researchers meant sodium intake that is over 5.99 grams daily and moderate is three to 5.99 grams daily. Meanwhile, around 10 percent indicated less than three grams daily sodium intake and merely four percent showed 2.3 or 1.5 grams which works within the national guidelines.

Results of the study showed that people with over six grams daily intake of salt have higher blood pressures over those who took less of it. For those in medium to low range, that is 5.99 to three grams, the effects on blood pressure were less dramatic.

Now, here’s the surprising irony. A low sodium intake or less than three grams dietary salt showed no effect on blood pressure—but resulted to more cases of and deaths from cardiovascular diseases.

“Importantly, the very large PURE study provides evidence that both high and low levels of sodium intake may be associated with an increased risk of death and cardiovascular disease outcomes,” Suzanne Oparil, M.D., professor of medicine, said in a statement.

Oparil, who is a vascular biology and hypertension program director at the Division of Cardiovascular Disease in the School of Medicine of University of Alabama at Birmingham, added that such study also indicated that bigger consumption of potassium in one’s diet corrects the adverse effects of high sodium secretion on blood pressure in consequences of cardiovascular health conditions.

Oparil said the study is notable advancement in extent, but just the same underscored the limitation of it. The PURE study, she explained, doesn’t necessarily resolve that low salt intake result to deaths and cases of cardiovascular diseases because of its observational nature.

To establish such impact or causality, there’s a need for a controlled, random outcome trial, which hasn’t been done yet. Oparil said that the argument of the study findings is on the cutback of sodium intake to levels presently recommended which is an isolated recommendation for public health.

The findings, “Association of Urinary Sodium and Potassium Excretion with Blood Pressure,” appeared in the New England Journal of Medicine.