A new European population study coordinated in Belgium raises questions about sodium and its effect on the heart.

Researchers followed 3,681 people, average age 40, for about eight years, testing sodium excretion in the urine. They found that systolic blood pressure (the top number) was slightly lower in those who excreted less sodium, but this didn't translate into a lower risk of cardiovascular death — in fact, those with lower sodium excretion had an increased risk of cardiovascular death. The findings were consistent in participants younger and older than 60 years.