“The War Over Salt, It’s the Food Industry vs. an Army of Medical Experts.”
—title of Melanie Warner’s New York Times article, 20081
The great bulk of scientific research has demonstrated that diets high in sodium increase blood pressure, which in turn increases the risk of cardiovascular and kidney diseases. Salty diets may also contribute to mild cognitive impairment, erectile dysfunction, obesity, osteoporosis, headaches, impaired vision, and edema. On the other hand, some studies, which were deeply flawed, indicated that reducing sodium consumption is unnecessary and even dangerous. The sharp disagreement between two warring camps of scientists has led to decades of confusion and delay in reducing Americans’ consumption of sodium—and in improving their health. Where have we seen that movie before?
In fact, similar scenarios have occurred in numerous other spheres of science and science policy. Powerful industries, aided and abetted by a handful of contrarian studies and sympathetic journalists, have “manufactured doubt,” arguing that the current scientific evidence was not sufficient to prove that asbestos and cigarettes caused cancer, that lead poisoned workers and children, that the burning of fossil fuels is changing our planet’s climate, and that certain pesticides and antibiotics harmed the environment, farmworkers, and the public.
But the salt situation is not entirely analogous. In those other science and policy battles, powerful industries sought to protect their profits by fending off government regulation. The salt industry is nothing compared to an ExxonMobil, Dow, or Philip Morris (and their respective industries) in terms of size and political clout. Moreover, food-grade salt represents only a minor portion of the sales of Morton Salt Co., North America’s largest salt producer, let alone the German mining company that now owns Morton. Cargill, another major salt manufacturer, also sells shiploads of soybean meal to China and truckloads of Shady Brook Farms turkeys to American supermarkets. Rather, salt is a cheap, minor ingredient in tens of thousands of processed foods manufactured by thousands of companies. Although the salt industry’s trade association, the Salt Institute, roared loudly over the years, its demise was barely noticed. It is the mainstream food industry that uses salt and has had the power to stymy effective government action.
Much of the food industry (buttressed by some academic researchers) has denied that the 100-plus randomized controlled trials (RCTs) proving that high-sodium diets increase blood pressure provide a sufficient basis on which to take regulatory action—even though no one doubts that high blood pressure causes heart attacks, strokes, and kidney disease. Taking a cue from other industries that have fought off public health actions, food companies have exaggerated the imperfections in the case against salt and demanded ever more proof that their products were harmful. To that end, one of the sodium skeptics’ key, if subtle, achievements was managing over the years to move the goal posts.
Health experts had long ago come to a consensus that high-sodium diets were a major cause of hypertension, and that was reason enough to lower sodium intakes. Half a century ago the White House Conference on Food, Nutrition, and Health felt there was enough evidence to reduce sodium levels to prevent or ameliorate hypertension. Forty years ago the first “Dietary Guidelines for Americans” advised Americans to consume less sodium. More than a quarter-century ago the National High Blood Pressure Education Program of the National Institutes of Health said that the “data clearly show” that high salt intake is “one of the important mass exposures that accounts for the generally unfavorable blood pressure distribution.”2
But beginning around 30 years ago opponents of sodium reduction began demanding further proof that lowering sodium would improve health, and not impair it. In particular, they wanted proof that lowering sodium would not just reduce blood pressure but also the risk of heart attacks and strokes. They demanded new RCTs on sodium and cardiovascular disease, which happen to be time-consuming, prohibitively costly—and not necessarily conclusive. Lawrence J. Appel, the hypertension expert at Johns Hopkins, says that their strategy seems to be “to raise the bar for evidence to a point where the evidence just will never be there.”3 Conducting more research to better understand the causes of health problems, and to find treatments for them, is certainly a good thing, and sometimes an RCT overturns long-held beliefs. But in the case of salt and health, many different strands of strong evidence have persuaded experts around the world that the costs of inaction far outweigh the chances that more research would overturn the consensus and demonstrate conclusively that lowering sodium intakes resulted in health risks. And waiting for that new research would greatly delay the adoption of life-saving programs and regulations.
The opponents of lowering sodium nevertheless amassed enough political influence to get anti-regulatory Congresses to fund the 2013 Institute of Medicine (IOM) and 2019 National Academy of Medicine (NAM) reviews. Those reviews based their recommendations almost exclusively on the relatively few studies that looked at direct links between salt and cardiovascular disease, downplaying the much richer body of evidence that salty diets cause hypertension, which in turn causes heart attacks, strokes, and kidney disease. Then, perhaps to the chagrin of those who demanded both reports, the IOM and NAM committees found that a national goal of 2,300 mg of sodium per day was safe and would lower disease rates. But the continuing controversy confused the public, and conducting those reviews delayed limiting sodium in school foods and implementing the Food and Drug Administration’s sodium-reduction plan. Also, because the committees relied primarily on RCTs, and there were no RCTs involving sodium intakes of under 2,300 mg per day, they could not endorse the sodium intakes under 2,300 mg that had been recommended especially for people over about 50, people with elevated or high blood pressure, and African Americans, all of whom have a higher risk of cardiovascular disease than the average adult.
Jeremiah Stamler, of the Northwestern University Feinberg School of Medicine, is considered by some to be the global dean of cardiovascular research, having conducted research about risk factors and prevention since 1948. (He has also been celebrated for standing up to, and ultimately suing, the communist-hunting House Committee on Un-American Activities in 1965.4) Back in 2002, Stamler and his co-author Paul Elliott published a rebuttal of a paper that lent support to those who were demanding evermore evidence before agreeing that people should consume less sodium. Stamler and Elliot summed up that position this way:
The proponents of the “do nothing” approach have no case for the status quo as the preferred public health option. In fact, the body of scientific knowledge affords no basis for valid debate; efforts to promote the idea that there is a scientifically grounded “controversy” in this area—as in the area of tobacco and disease—are scientifically unsound and detrimental to health.5
Aside from contending that the evidence is not sufficient to warrant policy change, companies play the hardship card by claiming they would suffer economic catastrophe if they had to reformulate their products or adopt new production methods. “Costs would go through the roof!” But time and time again, new regulations have proven to be “technology forcing.” That is, when confronted by new legal requirements, companies are often able to develop new technologies or manufacturing processes to meet or exceed the tougher limits—and sometimes even save money. (When it comes to lowering sodium intake, the “technology” might be as simple as using less salt.) Henry Waxman (D–CA), who for decades was a leading champion in the House of Representatives for protecting public health and the environment, observed:
In fact, automakers met with relative ease the ambitious [air pollution] standards they once claimed would destroy jobs and cast the economy into recession. . . . While industry claims often frame the debate, they are usually exaggerated, not accurate descriptions of the truth but tactics to stop unwanted measures, regardless of need or merit.6
Trade associations are among the most formidable lobbying entities in Washington; the most powerful food industry organization was the Grocery Manufacturers Association (GMA), but it had many allies representing the snack food, meat, poultry, restaurant, baked-goods, and other segments of the food industry. Waxman explained why trade associations typically oppose life-saving health and environmental legislation:
Because trade groups exist to represent the interests of an entire industry, their main concern is maintaining the happiness of all their members. Trade groups always push to weaken a bill to the point where none of their members object to it, which is why they are often such a negative force in the legislative process.7
I was pleased, if a bit surprised, that in 2007 and 2013, the GMA partnered with the Center for Science in the Public Interest on conferences aimed at “Getting to 2,300.” Our goal was to gently encourage companies to lower sodium to safer levels. But the GMA became increasingly reluctant to support sodium reductions the closer the FDA got to recommending a formal plan for achieving them. Developments in 2019, however, suggest that there will be less organized opposition to lowering sodium: the GMA transformed into the Consumer Brands Association and stopped lobbying against sodium reductions, and the Salt Institute closed its doors.
John Dement, a professor in Duke University’s Division of Occupational and Environmental Medicine, made the following comment about corporate-funded asbestos risk assessments, but it applies as well to the food and salt industries: “All they’ve accomplished is to try to generate doubt where, really, little doubt existed.”8
Echoing that is David Michaels, who was Assistant Secretary of Labor for Occupational Safety and Health in the Obama administration. In his book Doubt Is Their Product, he details how product-defense specialists manufacture doubt about second-hand smoke, workplace pollutants, and other health hazards. More broadly he explains how industry has institutionalized doubt, uncertainty, and delay by advocating a raft of bureaucratic hurdles that impede or permanently derail health and environmental protections.9 He reports that the Salt Institute had tried to use an obscure federal law, the Data Quality Act, to effectively “censor” the National Heart, Lung, and Blood Institute. Michaels called that law “a wonderful new weapon in the arsenal of all those who oppose public health and workplace regulations, as well as independent, serious science.”
A tactic parallel to “doubt” for opposing public health and environmental laws is to hold high the twin banners of “nanny state” and “personal freedom.” Those slogans have been invoked by libertarians and industries to characterize reform efforts related to everything from salt to soft drinks to tobacco to guns to class-action litigation, and they are intended to resonate with our inner beings as freedom-loving Americans. Example: the New York Post headline proclaiming, “The Nanny State’s War on Salt Won’t Make Us Healthier.”10
The ultimate practitioner of this tactic is the Center for Consumer Freedom (CCF). It pretends to be a “nonprofit organization devoted to promoting personal responsibility and protecting consumer choices.”11 In fact, its well-funded activities are apparently underwritten by the various industries—soft drink, meat, restaurant—that it defends with nasty full-page ads and angry websites. Almost everyone and everything is a nanny (the word is used 408 times on the group’s website): environmental and animal-welfare activists, the states of California and Mississippi, the Center for Science in the Public Interest, and most especially former New York City mayor Michael Bloomberg, who was depicted in a full-page newspaper ad wearing a dress, for advocating smaller soft drink containers and requiring calories on menus of chain restaurants. the CCF claims to be “devoted to protecting consumer choices,” but don’t expect the center to satisfy your choice to know who sponsors its campaigns—that is a closely held secret. All it admits to is support from “restaurants, food companies and thousands of individual consumers.” I’m skeptical of the latter, but we are not about to get any further information.
An important factor that aids and abets industry efforts to postpone, weaken, or kill corrective action is that products like salt and asbestos are not like airplane or automobile crashes. When the causes of injury, sickness, or death are obvious, society may take relatively quick remedial action. The problem is when substances plant seeds in childhood or early adulthood that do not blossom into heart attacks or cancer until decades later. That leaves plenty of room for arguments over the severity and causes of the harm. In many cases—lead, tobacco, asbestos, pesticides, greenhouse gases, and, indeed, salt—there were (and always will be) gaps in the knowledge about their health impacts. More studies were conducted, but critics pointed to more gaps. Finally, though, after decades of research, activism, argument, and delay, policy makers acknowledged that the evidence of harm was overwhelming and began instituting public health protections.
And so it is with salt, arguably the most harmful substance in our food supply. The overwhelming preponderance of evidence supports the near certainty that reducing sodium in the food supply would prevent tens of thousands of illnesses and deaths each year and save many billions of dollars. The time has come to end the indecision and delays, to stop waiting for that ever-elusive perfect proof. The time has come to declare the salt wars over, and for policy makers in the United States and around the world to act decisively to protect consumers from overly salty diets.