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BMJ No 7106 Volume 315 Letters Saturday 23 August 1997 Intersalt data Slow decremental change in dietary sodium load in whole populations is needed Editor, As authors of papers whose conclusions could be misused by the commercial salt interests,(1-4) we support the professional consensus in favour of a decremental reduction in dietary sodium load in whole populations everywhere. In our experience, individuals who endured abrupt reductions in sodium load from about 150 mmol to about 60 mmol found their new diet almost intolerable. Our research team and their families shared the experience of our subjects for the first week and agreed with them entirely. An important, though unfortunately unmeasured, consequence was that all subjects added more fat to their food in an attempt to make it taste of something, so that an abrupt reduction in sodium intake can in these circumstances increase rather than reduce overall cardiovascular risk. Doctors who rely on instructing their patients to abjure salt forthwith are careful never to verify compliance by measuring sodium outputs. Graham A MacGregor and Peter S Sever emphasise the delay of about one month before taste adapts to a new dietary sodium intake, a period that probably varies between individuals.(5) Given time for this adaption to take place, large reductions in dietary sodium may not be difficult; without it, a huge range of foods - all soups, breads, and most cheeses, as well as obvious items like Marmite, bacon, and kippers - disappear from one's diet. And when people have adapted and they can no longer stand the taste of what remains 'normal' for everyone else, they can no longer find a reasonable choice of prepared foods, eat out in a restaurant, or dine with their friends. We need a slow, decremental, across the board approach, strictly regulated so that competing food manufacturers don't cheat; successive targets should be based on evidence from continuing market research on how, or even whether, changes are perceived by consumers (nobody seems to have noticed the 20% reduction in sodium in bread). Without regulation, sodium load will continue to rise, as food manufacturers move toward North American levels of taste deception. Graham Watt Professor University Department of General Practice, Woodside Health Centre, Glasgow G20 7LR Julian Tudor Hart Professor International Section, Department of Primary Health Care, Royal Free Hospital Medical School, London NW3 2QU References 1 Watt G C M, Edwards C, Hart J T, Hart M, Walton P, Foy C J W. Dietary sodium restriction for mild hypertension in general practice. BMJ 1983;286:432-6. 2 Watt G C M, Hart J T, Foy C J. Effect of moderate dietary sodium restriction on patients with mild hypertension in general practice. J Hypertension 1983;1:18. 3 Watt G C M, Foy C J W, Hart J T, Gingham G, Edwards C, Hart M, et al. Dietary sodium and arterial blood pressure: evidence against genetic susceptibility. BMJ 1985;291:1525-8. 4 Watt G C M, Foy C J W, Hart J T. Comparison of blood pressure, sodium intake, and other variables in offspring with and without a family history of high blood pressure. Lancet 1983;i:1245-8. 5 MacGregor G A, Sever P S, Consensus Action on Salt and Hypertension. Salt - overwhelming evidence but still no action: can a consensus be reached with the food industry? BMJ 1996;312:1287-9. Home | Current issue | Past issues | Classified ads | Career Focus | Feedback Collections | About this site | About the BMJ | BMA | Medline