A study published in the Journal of the American Heart Association shows that as dietary sodium levels go up over time, the risk for high blood pressure may also go up. U.S. government dietary guidelines recommend consuming no more than 2,300 mg of sodium a day, equivalent to about two-thirds of a teaspoon of salt, and that people with existing high blood pressure or risk factors for it limit total sodium to 1,500 mg daily.
The researchers used urine tests from checkup appointments to estimate the dietary salt intake of 4,523 Japanese adults without high blood pressure. The participants, aged 22 to 85 years old, had annual physicals including sodium tests and blood pressure measurements. The researchers used these records to follow people for three or more years to see if they developed high blood pressure. During the study, 1,027 individuals developed high blood pressure, including 26% of the men and almost 17% of the women.
The researchers found that having higher sodium levels at the beginning of the study and showing greater increases in sodium levels each year were both tied to higher risk of developing high blood pressure. At the start of the study, the participants were consuming an average of 4,200 mg of dietary sodium per day. Those who would go on to have high blood pressure were eating an average of 4,500 mg per day.
The researchers concluded that “dietary sodium intake plays an important role in the development of hypertension in the population at large.”
