Blood pressure is the most important factor in the development of strokes and other cardiovascular diseases. The dietary intake of salt(sodium chloride) has a role in determining blood pressure and hypertension . This is well shown in clinical trials. This finding applies regardless of age, gender, ethnic origin, base line blood pressure and body mass.
Salt intake is a good predictor of the incidence of cardiovascular events.
There have been few studies on the benefits of reduced salt intake on clinical outcome as opposed to reducing blood pressure.
Cook and colleagues (BMJ 2007, vol 334, 885-8), now show the long term benefits of reduced dietary sodium on cardiovascular disease in people participating in controlled randomised trials of hypertension prevention and follow-up studies . More than 3000 participants without hypertension were randomised to a reduced sodium intake for 18 months or to a control arm. The reductions in sodium intake were 44 mmol/day and 33 mmol/day ( 2.6 and 2.0 g of salt), respectively. The results show that people originally allocated to either sodium reduction group had a 30% lower incidence of cardiovascular events in the next 10-1.5 years, irrespective of sex, ethnic origin, age, body mass, and blood pressure.
In 1985, the World Health Organization recommended that the average salt intake should be reduced to 5g per day or less. However, few countries- have policies for targeted reduction in salt intake.
In Westernised countries, people derive salt mostly from bread and processed food and only a small proportion comes from added salt. Any reduction therefore needs the involvement of the food industry.
In many developing countries, like those of sub-Saharan Africa, where the main source of salt is still added salt ,there should be a place for education
Cook et al BMJ 2007, vol 334, 885-8
Cappuccio BMJ 2007, vol 335, pp 859-60
- Martin Eastwood