With heart disease and stroke remaining the No. 1 killer globally, the World Heart Federation is asking people to cut down on their use of salt.

If people reduced their normal intake of salt by just half a teaspoon each day, or three grams, millions could be saved from dying of these ailments, the Geneva-based non-governmental organization said Sunday.

Deaths from stroke would drop by more than 20 per cent by reducing intake this small amount, and deaths from heart disease would decrease by more than 15 per cent, said the federation's president, Shahryar Sheikh, in an interview from Pakistan.

"Hypertension is the most important and the most prevalent risk factor right now in the world," Sheikh said. "So, in the dietary change one can get a very good result, even a small little thing like the reduction of salt can make a fair amount of difference in your blood pressure, which can then give you a lot of beneficial effects."

Every year, 17.5 million people die of heart attacks and strokes, according to the federation.

The theme for World Heart Day this year is "Know Your Risk." The group is also encouraging people to adopt healthy lifestyles and go for periodic health checks.

A diet high in salt increases the risk of developing high blood pressure, a factor in cardiovascular disease.

The federation said high blood pressure affects more than a billion people worldwide, but that number is predicted to rise to more than 1.5 billion by 2025.

Other risk factors for developing cardiovascular disease include being overweight, a lack of physical exercise, smoking and drinking too much alcohol.