A team of researchers from Bar-Ilan University examined 20 years of electronic health records from more than 407,000 healthy adults enrolled in Leumit Healthcare Services, one of Israel’s largest health providers. Their findings, published in the peer-reviewed European Journal of Preventive Cardiology, suggest that individuals with sodium levels at the higher end of the normal range face significantly elevated risks for high blood pressure and heart failure.

Till now, the 135–146 mmol/L sodium range was broadly accepted as “normal,” with little clinical concern unless levels were outside this band. But the Bar-Ilan study found that otherwise healthy individuals with sodium levels between 140–146 mmol/L still face measurably higher risks of developing chronic cardiovascular conditions.

For those with levels above 143 mmol/L, the risk jumped to 29% for hypertension and 20% for heart failure.