The Dash, The Salt, Its Institute and Their Lovers
I just started teaching my course for the second year medical students. I dread the beginning, the first morning as I wake up I cannot stop myself from thinking how much other work I have and what an imposition it is on my time and how none of the students are going to be interested and it is such a difficult subject and everybody will be turned off and being young they will constantly want to be spoon-fed and taught how to connect A to B and B to C. But the minute I go into my small group of 25 students, all it takes is one alert student and the slightest look of interest to make me feel foolish about my own gripes and stupidity and to be happy to speak to them; I hope I am interpreting these looks correctly, but no matter. But I think this may turn out to be a better year than last year where everybody seemed tense and ill at ease. I still cannot believe that a class of 150 students can have a personality. How could that be! Anyway we started wading through the intricacies of how salt is handled by the kidney. You could call the course Salt and its Discontents and is at the heart (and blood pressure) of the problem. On monday returning from NIH I found on the Delta Shuttle (can you believe it costs $309 each way!) that a small can of V8 juice has almost 1 gram of sodium! I know it is the best preservative; but I also know that most prepared and canned foods have a bitter taste. The higher the salt in a food the less you taste bitter and the more you taste sweet. Needless to say it has not escaped the notice of the Food Industry that salt makes food taste better. Hence The Salt Institute, an amazingly powerful lobbying group that tries to fight everything to do with salt and health. They learned a new trick (really an old trick in politics); Make the subject controversial! So they have funded a few studies which raise some vague questions about whether there is a relationship between salt and high blood pressure. Suddenly, everywhere you look, in the New York Times and elsewhere, writers say that it is controversial that high salt in the diet cuases high blood pressure. Forget about studies of populations who eat a lot of salt like the northern Japanese have a very high rate of high blood pressure and strokes; forget about small populations living in Pacific Islands who fish in inland fresh water fish (and so have a low salt intake) have low incidence of high blood pressure while their genetically similar cousins who live on the sea shore (and eat salty fish) have a higher incidence. Experts in the field don't think it is controversial, there maybe one or two researchers who say it ain't necessarily so. But the overwhelming evidence is that there is a relationship. Large organizations like the NIH, American Heart Association and others believe there is a relationship. Of course that can be cast as an orthodoxy and can be dismissed as political correctness these days. In the most important recent study called the DASH trial scientists lowered salt intake in patients with various levels of high blood pressure and found that this dietary modification caused lowering of blood pressure. Now The Salt Institute led the fight to establish a law called the Data Quality Act(who could be against it!). In this Law anybody could ask for the primary data of large experiments funded by public moneys.The law written by an industry representative would allow all industries to challenge all trials by looking at the primary evidence. The Salt Institute wants to take these studies and probably extract a few patients from it and show that these few did not respond to decreased salt intake with lowering blood pressure. They will then publish them and say, See! We told you it is controversial; even in the DASH study. NIH is fighting back, but it is not likely they will win. Remember, what is wrong with seeing both sides of a controversy; It is only Fair!