Voluntary industry reductions in salt content and taxation on products containing salt in 19 developing countries could reduce the number of deaths each year from cardiovascular disease (CVD) by 2-3 per cent in these countries. The preliminary data recently presented at the World Congress of Cardiology are the first findings from a new report from Harvard that will be published later this year.

The study set out to assess the cost-effectiveness of two interventions -- voluntary salt reduction by industry, and taxation on salt -- in 19 developing countries, that represent more than half of the world's population. The required salt reduction levels were modeled on the UK Food Standards Agency experience which set a series of targets for individual food products that have led to a net intake reduction, so far, of 9.5 per cent overall in the country. While a taxation increase of 40 per cent on industry prices (similar to tobacco), determined by previous work to lead to a 6 per cent reduction in consumption, was also evaluated.

The analysis found that both strategies would be save money by reducing the number of people needing treatment for hypertension and CVD events such as myocardial infarction (heart attacks) and stroke. Moreover, the study found that these two strategies could reduce the incidence of myocardial infarctions (heart attacks) by up to about 1.7 per cent and 1.47 per cent in China and India respectively. Reductions would also been seen in the incidence of stroke of 4.7 per cent in China and 4 per cent in India.

"These results show that strategies to reduce sodium consumption, even by modest amounts, could lead to significant reductions in CVD mortality in developing countries and potentially save overall healthcare costs associated with these diseases," said Dr. Thomas Gaziano, assistant professor, Harvard School of Medicine. "In developing countries, where the burden of CVD is highest, these simple steps could deliver a significant long-term impact and must be something that governments trying to manage rising healthcare costs should consider."

CVD is the world's biggest killer, claiming 17.3 million lives each year. More than 80 per cent of CVD deaths occur in low- and middle-income countries. Projections suggest that CVD will remain the single leading cause of death, and by 2030 will be responsible for 23.6 million deaths each year.

Salt intake and cardiovascular disease

Elevated sodium intake has significant implications for cardiovascular health. A positive relationship between salt intake and high blood pressure has been established, while salt reduction trials have revealed that a decrease in salt intake is directly related to a decrease in blood pressure.

Hypertension (high blood pressure) is one of the major preventable risk factors for premature death from CVD worldwide. High blood pressure contributes to around half of all CVD and the risk of developing CVD doubles for every 10-point increase in diastolic blood pressure.

High blood pressure that is left untreated can greatly increase a person's risk of developing CVD. Treating raised blood pressure has been associated with a 35-40 per cent reduction in the risk of stroke and at least a 16 per cent reduction in the risk of myocardial infarction.