I started this blog last spring more or less just to test out blogging lightheartedly about food. However, I have just read Bon Appetit‘s appalling “Health Wise” column from the May issue, “The Saline Solution” by John Hastings.
I do actually love to cook and eat well, and that’s my main purpose for this blog, but seeing this kind of blithely irresponsible “health” advice on salt makes my blood boil (not appetizing). Worse, it starts dragging me back to my work roots and up on my soapbox (also not appetizing, though kind of fun), because I trained as a biochemist and worked for several years as a science journalist. I worked for the National Heart, Lung, and Blood Institute at NIH at the time some of the bigger studies Hastings refers to were first being published. It was my job to know about them and write about them in plain (and preferably short) English for Congress and the public. To do it I talked to national experts, interviewed the leaders of the National High Blood Pressure Education Program, and combed through a century’s worth of research on salt and high blood pressure.
But you don’t have to be a scientist to find this stuff out. Descriptions of the studies AND their updates AND the reasoning behind the basic public health guidelines calling for Americans to watch their salt AND how to do it without eating a restricted diet of cardboard and baby cereal are all easily available from the NHLBI web site or the American Heart Association.
Hastings, a former editor of Prevention and health column contributor to O, the Oprah Magazine, is someone you’d expect to be reasonably accurate in reporting health research findings. But here he gets the science on salt and high blood pressure just about as backwards and upside down as he possibly can.
Worse yet, he does it in a strangely breezy, cheerleading tone that’s really hard to believe.
Hastings’ argument goes something like this:
…here’s a little secret: salt isn’t a problem. If that sounds crazy, it’s because the public health message about salt causing high blood pressure has been very, very effective, and it’s backed by reams of scientific research…Upon this, nearly everyone agrees. The controversy arises when you ask experts about the connection between salt intake and high blood pressure…All of this is fantastic news for those of us who are already cooking with high-quality meats and farmers’-market produce…
Did you follow all that? Probably you felt like you did for the few seconds you were reading it, but look again and you start to pick out the self-contradictions–“If it sounds crazy” that salt isn’t a problem, “it’s because the public health message that salt causes high blood pressure… is backed by reams of scientific research.”
Well, yes it is. The way Hastings phrases it, you’re supposed to think that was a bad thing, that health research in general and carefully designed tests of the effects of diet on cardiovascular health in particular are part of some kind of unnamed conspiracy against the public’s right to eat every bit of salt it can get. Personally, I’d rather that broad public health messages were backed by reams of scientific research rather than by some diet guru or brand-name chef’s nutritional fantasy that will help sell his next book or tv program, or–more realistically–by corporate marketing and pressure campaigns from big pharma and big agro. Of course, it’s less profitable if people simply eat less salt–and less processed food–and never develop hypertension in the first place than if they eat salt like it’s going out of style and call it gourmet, and then have to make up for their diet by taking hypertension pills…hmm. Food, Inc., anyone?
“Upon this nearly everyone agrees”, but somehow there’s still a great controversy over it? Really? No. Not really.
The vast majority of salt researchers look at the bulk of the study results and conclude–repeatedly, for decades now–that salt is, in fact, a direct and modifiable risk factor for hypertension (high blood pressure). Which is both a disease in its own right and a leading risk factor for heart disease, stroke, and chronic kidney disease. Combine that with the fact that the average current salt intake is about twice what the consensus guidelines recommend and that more than half the adult population in the U.S. is crossing the line into overweight and obesity–and…well, yes.
Salt IS actually a health problem for most people. Gee.
The Bon Appetit article is a jumble of self-contradictions and serious misinterpretations of the findings from two older salt research studies, one of which has since been revised, plus a cherry-picking recent review that comes to a different conclusion about salt than most of the other reviews of the same data on diet and health. That one comes from the lab of Mickey Alderman, an otherwise eminent researcher who just happens to be a long-time, much-trumpeted advisor and consultant for the Salt Institute.
Hastings doesn’t indicate that he interviewed the man or even recognized his name on the journal article, but he should have. Anytime somebody in the media wants to come up with the magical–and really, really popular–conclusion that lots of salt, any day, any time, anywhere, please add more, is perfectly harmless and even good for you, they go to Mickey Alderman because they can paint him as a lone hero against the Food Police (the typical name they give the National Institutes of Health and the American Heart Association in such cases). Because what Alderman will say–with precision, but with disregard for the bigger public health picture–is that high salt intake isn’t directly proven to cause death from cardiovascular disease.
And it isn’t. It can’t be proven directly in a well-controlled diet study large enough to reach statistical significance, because that would require thousands of participants to follow a carefully prepared diet throughout their entire lifetimes, with no deviations for dates, wedding receptions, pizza parties, etc., and it would take 50-75 years to collect the majority of the data. You’d literally have to wait until most of the participants died before you could make a public health recommendation about salt. And the cost of doing that study “right” would run into the billions. It would bankrupt the federal science budget. And maybe a few other budgets as well.
That’s why the NHLBI and the AHA have sponsored studies that look at signs of developing cardiovascular illness–heart attacks, stroke, phlebitis, high blood pressure, kidney disease–rather than death. When you look at these ailments, you find that dietary salt actually matters quite a bit–contrary to what Hastings thought he understood from the studies he mentions.
The original DASH (Dietary Approaches to Stop Hypertension) feeding study of the late 1990s, which Hastings misinterprets in Bon Appetit, tested a total-diet approach of low-to-moderate intake of meats and saturated fats with higher intake of vegetables, fruits, whole grains and low-fat dairy. The sodium levels between the test and control groups were kept equal because sodium had already been identified as a risk factor for high blood pressure, and the researchers wanted to test the combined effect of increased potassium (from plants) and increased calcium.
But DASH has since been revised and retested to include a direct comparison of salt levels in diet. In the new version, the researchers did indeed find that lowering salt lowered blood pressure even further than the standard DASH diet. It’s not a secret. Why didn’t Hastings look at it as well?
Key studies like Trials of Hypertension Prevention and DASH-Sodium have demonstrated that lowering dietary salt definitely helps prevent “mission creep”–the gradual rise in blood pressure that Americans have come to take for granted as they age–and that cutting sodium can help people with hypertension control their blood pressure with less medication and reduced side effects. That’s a major benefit to quality of life–if you have high blood pressure, would you really want to have to wait another 30 years for that information?
Hastings’ other main claim is that since we get three quarters of our dietary salt from packaged and processed foods, it’s fine to salt our home-cooked food as heavily as we want. The Mayo Clinic information he relies on for this stunning bit of illogic comes from a British study from the late 1970s and early 1980s that showed that processed foods were the source of 77 percent or so of the average dietary sodium and that home cooking wasn’t at fault.
It was a great study at the time, very neatly designed, and the results were a real eye-opener to consumer vulnerability. But while the findings may have been true 30 years ago, the study may not be relevant today because our eating patterns have shifted–people are eating out more per week, average portions are bigger, and common processed foods for home consumption have also gotten a lot saltier over the past 20 years. Breads and cold breakfast cereals are edging up over 200 mg. sodium per serving, jarred pasta sauces are 450-700 mg. per serving, and a single Lean Cuisine or South Beach Diet frozen microwaveable “meal”–the popular choice among office workers–can range 600-1200 mg. sodium for a 270-calorie item. So even if the percentages stayed the same between processed and home-cooked foods, the overall salt consumption is a lot higher.
And certainly this study’s findings are particularly irrelevant and inappropriate if you use them as an excuse to throw extra salt into all your home cooking, as Hastings claims to do! Again, it doesn’t take a Ph.D., just some common sense, to figure that it’s not going to make the food healthier. It doesn’t show any kind of culinary skill or imagination either.
I don’t demand that a health journalist at Hastings’ level have extensive laboratory or clinical trials experience. But a little common sense would help. If the bulk of the research suggests that eating a lot of salt is harmful and only one or two studies suggest otherwise, what’s YOUR best bet? And any journalist at Hastings’ level should know how to do a basic background check on his or her chosen experts.
Public health policy isn’t some legalistic word game requiring absolute 300 percent certainty before anyone can make a public health recommendation. It’s a pragmatic way to save lives and reduce the rate of illness in the population in real time by announcing better treatment and prevention recommendations as they come along. Prevention guidelines for hypertension include lowering dietary salt because that’s the best-guess recommendation based on the bulk of the evidence available today. It may not be perfect, it may not be popular and it may not be profitable to the pharmaceutical manufacturers. Or the processed food industry.
The Salt Institute and the food processing industry in general have demonized salt moderation very successfully, but that’s no excuse for John Hastings or Bon Appetit to do the same. I would even venture that it’s any good food magazine’s job to explore dishes and techniques that don’t kill the cook. Or the guest.
Filed under: cooking, DASH Diet, Food Politics | Tagged: Bon Appetit, cardiovascular disease, consumers, DASH Diet, diet, Food Politics, heart attack, heart-healthy, hidden salt, high blood pressure, hypertension, kidney disease, low-salt, NHLBI, NIH, nutrition, politics, Prevention, salt, stroke |