People with high blood pressure could bring it down to an acceptable level with one site change that is as powerful as taking medication, according to a study. Cutting one teaspoon of salt from your diet every day could work as well as taking blood pressure medication, a study has found.

Norrina Allen, professor of preventive medicine at Northwestern University’s Feinberg School of Medicine, said: "This is the first study to show that people who are already on blood pressure medication can lower their blood pressure even more by limiting sodium. And regardless of medication, we found 70% to 75% of people are likely to see a reduction in their blood pressure if they lower the sodium in their diet."

High blood pressure, known as hypertension affects 1 in 3 adults. It can lead to heart attack, heart failure, kidney damage, and stroke, according to the World Health Organization.

The condition is sometimes branded the "silent killer" as there are no symptoms. The study, published in in the Journal of the American Medical Association, assigned 213 people ages 50 to 75 to one week of a high- or low-sodium diet. After eating that diet for seven days, each person then switched to the alternate diet. About a quarter of the participants had normal blood pressure, while another 25% had untreated hypertension. Of the remaining group, 20% had blood pressure under control, while 31% did not, reports The Mirror.

During the high-salt week, people ate their normal diet, along with two bouillon packets, each containing 1,100 milligrams of sodium. During the low-salt week, people ate foods with low sodium, purchased and given to them by dietitians. The goal was only 500 milligrams of salt a day, a dramatic drop.

The drop in blood pressure while on the low-sodium diet was quick and dramatic, according to the study. Prof Allen added: "Compared to their normal diet, people reduced their blood pressure by about 6 millimeters of mercury, about the same effect you’d see for a first-line blood pressure medication. In addition, that drop happened pretty quickly and was consistent for people with normal blood pressure, slightly high blood pressure, or those already on medications."