Today, the US House of Representatives will vote on a "cap-and-trade" climate change bill embodying the mindset of Al Gore's "inconvenient truth" argument. Thus, today's Wall Street Journal editorial, a last-gasp attempt to deflect the Democrat's legislative steamroller on Capitol Hill, notes that popular skepticism on "climate change" is on the rise around the world. Notably, the argument isn't being framed that "we can't afford it" in troubled economic times; no, the argument is advanced that the science underlying the entire response is flawed: scientific doubts are growing that man-made "greenhouse gas" emissions are a threat. The WSJ attributes the rush to pass cap-and-trade and its multi-trillion-dollar cost-shifting scheme to global warming proponents' foreboding about the concept's eroding prospects.
If the science of global warming is changing, the concept has had prominent skeptics from the beginning. Doubters were overwhelmed by alarmist activists who made dire warnings a favorite media theme. Efforts to secure access to the scientific studies underlying the global warming promotion have been systematically thwarted. Proponents have labeled skeptics as "deniers," affixing them with a popular image akin to those who deny the well-documented Holocaust.
Whatever our personal views on the legitimacy of the science on global warming, there is an eerie parallel process running in the nutrition-and-health debate.
Prominent independent scientists note the absence of evidence for a health outcomes benefit among those consuming low-sodium diets. Questions remain unanswered about the efficacy of reducing and sustaining lower population sodium intakes and, in particular, about the untested hypothesis that substituting low-sodium foods will reduce an individual's sodium intake. Independent analysis of government-funded data is systematically foreclosed. Skeptics are lambasted personally for failing to toe the policy line in a broad pattern of intimidation. And the food industry has resorted to an acceptance of the sodium hypothesis and based its defense on the unfeasibility of some of the remedial policy responses (akin to complaints that cap-and-trade would export American jobs and crush economic vitality). Finally, alarmists press for urgent action with warnings of dire consequences.
The WSJ editorial concludes:
[Climate change opponents] in the U.S. have, in recent years, turned ever more to the cost arguments against climate legislation. That's made sense in light of the economic crisis. If Speaker Nancy Pelosi fails to push through her bill, it will be because rural and Blue Dog Democrats fret about the economic ramifications. Yet if the rest of the world is any indication, now might be the time for U.S. politicians to re-engage on the science.
Those who would stand in the path of cap-and-trade have an uphill fight against a Congressional majority with vigorous White House support. Science hasn't been able to gain traction in the public debate.
The very different scientific issues at play in the salt and health controversy are headed down this same pathway unless we can, as the WSJ says, "re-engage on the science."
One other parallel: Climate, like physiology, responds to immutable laws of nature, whether we understand those principles or not and whether our policy responses anticipate the consequences of our interventions.
So, let's work for re-engagement on the science, greater data transparency and, above all, a focus on the quality of the data upon which our momentous public policy decisions are based.
Canada is currently in the midst of a national initiative aimed at reducing the sodium content of the diets of Canadians. It has appointed a Multi-stakeholder Working Group on Dietary Sodium Reduction (Sodium Working Group) to oversee this process. The compulsion to reduce sodium in Canada is being driven by the international group of advocates belonging to WASH (World Action on Salt and Health) who believe that significant salt reduction will reduce population-wide blood pressure to a point where many thousands of lives will be saved. These assertions are based on the speculations of some blood pressure experts – not on any scientifically derived clinical data. In fact, there are many blood pressure experts who disagree with this notion, but despite this, the Canadian Government has embarked upon a journey that appears to have only one outcome – a reduction in salt consumption.
The Salt Institute has taken part in some of the meetings of this Sodium Working Group and has urged a full consideration of all the scientific evidence and has cautioned prudence in implementing population-wide salt reduction programs since the data on health outcomes clearly does not warrant such an approach.
Today, the Canadian Medical Association Journal published a special report on “National trends in rates of death and hospital admissions related to acute myocardial infarction, heart failure and stroke, 1994–2004, ” by J.V. Tu et al. The report, also covered on “theHeart ” website, states that the rates of death from cardiovascular disease, including myocardial infarction, stroke, and heart-failure mortality rates, have significantly decreased in Canada over a recent 10-year study period. From 1994 to 2004, cardiovascular disease mortality declined 30%, while the rate of myocardial infarction, stroke, and heart-failure mortality decreased 38.1%, 28.2%, and 23.5%, respectively. This precipitous decline has taken place without any reduction in the consumption of salt. In fact, in a recent Salt and Health Newsletter , the Salt Institute compared Canada’s excellent cardiovascular performance over the last 30 years, without salt reduction, to Finland’s – the only country to achieve significant salt reductions during the same time period. The data, taken from the WHO Global Cardiovascular Infobase, shows how much better Canada fared over Finland. This latest report in the Canadian Medical Association Journal confirms this fact
Since Canada has done so well in reducing cardiovascular disease outcomes, it brings the Canadian sodium reduction initiative into serious question. The salt reductionists' dire predictions on salt and cardiovascular heath appear to be incorrect because Canada is doing very well indeed. In fact, today’s report in the Canadian Medical Association Journal states that, despite Canada’s great overall cardiovascular performance, more women than men are dying of cardiovascular disease, particularly elderly women. As it happens, according to a very recent Statistics Canada report, “Sodium consumption at all ages ,” women eat far less salt than men and elderly women in particular, are the one group that consumes the least amount of salt and is closest to the Government’s sodium intake goals – yet their cardiovascular performance is the worst of all Canadians.
Perhaps, it is time for the Government to actually read and respect its own data and acknowledge when it is well off.
Thanks to an expensive and extended PR campaign, most Americans know that blood pressure is an important indicator of their cardiovascular health. Higher is not better. But a new survey Web-published recently discovered that 75% of adults with high blood pressure are not at all familiar with another "number" that may be even more important in determining their chances of a stroke or heart attack. Only one in four has any inkling of the function and critical role of the body's renin system, even though 89% of those surveyed told the pollsters they wanted to understand what was causing their high blood pressure. Medical News Today reported the survey results.
Many things impact blood pressure. And lower BP isn't always better, though the greater public health risk is the high and rising number of people with above-normal BP. Salt is among those factors. So is renin. Renin? That's what three-fourths the respondents said. Only 2% said they were very familiar with the role the renin system plays in their body, though one quarter (25%) consider themselves at least somewhat familiar. Ominously, even after respondents were given descriptions about the role the renin system plays in the body, only 23% were able to correctly describe it (by regurgitating the information they had just received. No wonder so many people uncritically embrace the proposition that lowering dietary salt will improve their health. They just don't understand what's going on in their bodies.
Renin is a key regulator of BP. It's a proteolytic enzyme produced in the kidney that plays a major role in the release of angiotensin which the body secrets to tighten up blood vessels to keep BP up if the body senses it is falling to an unhealthy level. Many anti-hypertensive drugs block renin activity.
Renin levels are associated with a 430% increase in heart attack incidence according to a study published back in 1989. Fifteen years earlier, the foremost investigator into renin's role, Dr. John Laragh, landed on the cover of Time magazine for his pioneering work. But that was more than 30 years ago and the government's PR blitz on salt has buried those insights.
What does this have to do with salt? Salt reduction triggers elevated levels of renin. Didn't read that on the NHLBI website, huh? It's true. Reducing intakes of dietary sodium prompts the kidneys put crank up their production of renin, increasing your odds of a heart attack. The government knows this (I personally notified FDA Commissioner David Kessler back in 1989), but it's another "inconvenient truth" it prefers to ignore. It is one of the "unintended consequences" of salt reduction that, in sum total, negate any health benefit of lowering dietary salt to reduce BP.
Well, now at least you can add yourself to the 23% who are at least "somewhat familiar" with the crucial BP role of renin.
The survey was sponsored by Novartis Pharmaceuticals Corporation and conducted by Harris Interactive. It included more than 2,400 US adults ages 18+ of whom more than 700 reported elevated blood pressure. In releasing survey results, RealAge.com declared: "The results of this survey reinforce the need for education, particularly around the renin system. Targeting the renin system is a key to regulating blood pressure. Our hope is that by helping the public better understand the physiology of high blood pressure, we can motivate those with the condition to adapt a healthier lifestyle and ask their physicians about treatment options that target a key source of blood pressure."
Everyone knows prevention is better than remediation. That's true of removing snow and ice from roadways, preventing mineral deposits on hot water appliances or avoiding personal accident or injury.
In health, that translates to preventing disease or treating the afflicted. In our national healthcare debate, everyone's for prevention as much as everyone is for "reform." With trillions of dollars at stake, we should be asking ourselves whether it's true that "an ounce of prevention is worth a pound of cure." Is prevention cost-beneficial and, if so, is all prevention justified or should our prevention efforts be targetted where they'll deliver the biggest bang for our bucks? Time magazine made prevention its cover story this week, summarizing the issue:
As the cost of health care continues to climb (60% of U.S. bankruptcies in 2007 were due to medical costs), the health of our nation is not getting any better. Heart disease remains the No. 1 killer of Americans (as it has been for all but a few years since 1900), our collective waistline continues to bulge, diabetes rates march ever higher, and after steadily declining in recent decades, the smoking rate among high schoolers is leveling off. The U.S. boasts the best cutting-edge medicine in the world, yet 75% of our health-care costs are attributable to chronic, preventable diseases. In all, about 40% of premature deaths in the U.S. are caused by lifestyle choices — smoking, poor eating and inactivity.
But while prevention — intervening in patients' lives before they get sick — has long been part of the medical lexicon, programs to educate and encourage patients to adopt healthy behaviors have never truly been embraced. Ours is a system that rewards pills and procedures and nurtures a clinical culture in which the goal is primarily to fix what goes wrong. "I never saw a well patient in my life," says Cosgrove of the years he spent as a heart surgeon. "They were all sick. We are in the sickness business. We need to get into the health business." This idea is at the heart of how President Obama wants to reform health care in America; he argued that the U.S. medical system is designed to provide disease care rather than health care. In a letter to Senators drafting health-care-reform legislation, Obama cited the [Cleveland Clinic] as a model: "We should ask why places like the Mayo Clinic in Minnesota, the Cleveland Clinic in Ohio, and other institutions can offer the highest quality care at costs well below the national norm. We need to learn from their successes and replicate those best practices across our country," he wrote.
Will prevention work? And will our health system finally embrace the strategy over prescriptions and procedures? We don't have many other options. Prevention is a timeless idea, one our species has always practiced: pioneers preserved food to prevent starvation in the winter; modern workers invest in 401(k)s to prevent destitution when they're older. Applying the same ethos to medical care ought not be that hard — especially since the country's health, economic and otherwise, may depend on it.
In fact, the President is personally modeling as well as cheerleading the prevention effort. Capitol Hill newspaper Politico carried a story earlier this month by Carrie Budoff Brown entitled "Coach Obama: Shape up now." Brown points out that the prevention push is controversial ideologically ("To some, it smacks of a 'nanny state on steroids'"), noting that Obama has imported into the senior ranks of his Administration "officials who, in their previous jobs, outlawed trans fats, banned public smoking or required restaurants to proivde a calorie count with that slice of banana cream pie." She warns: "Obama needs to (avoid) coming across as a public scold or killjoy." She quotes a frustrated David Harsanyi, a Denver Post columnist and author of the book Nanny State: How Food Fascists, Teetotaling Do-Gooders, Priggish Moralists and Other Boneheaded Bureaucrats Are Turning America Into a Nation of Children, saying: “If you care about the sorts of things I do, then you are going to be losing big-time for the next four to eight years,”
Obama's effort is more than ideology, however, Brown continues. The major argument is that prevention will save money.
The public health community has worked intensively in recent years to build a body of evidence in support of the very initiatives Obama and lawmakers are now embracing. They frame the issue as one of money: Chronic diseases account for 75 percent of the nation’s $2 trillion in medical costs, according to the Centers for Disease Control and Prevention. And if the government encourages healthful lifestyles, it could slow the rising cost of health care, though the exact savings are debatable.
Yes, prevention IS debatable. Earlier this year, Rutgers economics professor Louise B. Russell addressed the subject in an article in Health Affairs, "Preventing Chronic Disease: An Important Investment, But Don’t Count On Cost Savings." Dr. Russell explained:
Over the four decades since cost-effectiveness analysis was first applied to health and medicine, hundreds of studies have shown that prevention usually adds to medical costs instead of reducing them. Medications for hypertension and elevated cholesterol, diet and exercise to prevent diabetes, and screening and early treatment for cancer all add more to medical costs than they save. Careful choices about frequency, groups to target, and component costs can increase the likelihood that interventions will be highly cost-effective or even cost-saving.
Russell's been quoted a lot recently as the healthcare debate heats up. She told Janet Adamy of the Wall Street Journal that many previous government prevention efforts aimed at costly chronic diseases have had little success in reducing illness or costs: "It is not going to cut costs. We already do a lot more prevention than other countries. We are not healthier." Adamy's report continues:
[Russell's] findings don't question the benefits of a healthy lifestyle, and many preventive measures are effective. The problem is that when testing becomes too widespread, or heavy investments are made in monitoring people with chronic diseases, the rewards often fail to match the costs.
The Congressional Budget Office, in a December report, concluded that greater use of preventive care would at best generate modest reductions in costs over 10 years, and might even result in increases.
One reason cost savings are hard to achieve, according to Prof. Russell, is that much of the money spent on disease prevention goes for people who aren't going to get sick anyway. Also, people have trouble making difficult lifestyle changes, such as taking up regular exercise or eating healthier food.
A report published in the New England Journal of Medicine last year examined 279 spending ratios in published studies of health-oriented prevention measures, and another 1,221 on treatments for people who were already sick. Some measures clearly saved money, like screening men in their early 60s for colorectal cancer.
But the report concluded that most preventive measures reviewed didn't save money. For instance, screening all 65-year-olds for diabetes would cost $590,000 for every healthy year of life it adds over just screening people that age with high blood pressure.
Medicare has conducted seven pilot programs in the past decade testing the theory on some of the most costly chronic diseases. Each showed little if any cost savings or measurable improvement in patients' health.
So prevention isn't the magic pill that "everyone" believes it to be. But what I'd call "smart prevention" certainly should play a central role in addressing our national health needs. Smart prevention has two principles: 1) it's evidence-based, not playing to the crowd and, 2) it's selective, focused on interventions and individuals or tightly-defined groups who will benefit. [By that standard, of course, universal salt reduction would be abandoned as a policy].
Dr. Russell would seem to endorse this approach. Her Health Affairs article avers:
Prevention can be a cost-effective, sometimes cost-saving, component of managing established chronic conditions. For example, at $16 per person (1995 dollars), or about $25 today, vaccination against pneumococcal pneumonia reduces medical spending for adults ages 50-64 with congestive heart failure, chronic lung disease, and diabetes, and other chronic conditions...
But, she concludes:
Over the past four decades, hundreds of sutides have shown that prevention usually adds to medical spending. ... 80 percent add more to medical costs than they save. Careful choices about frequency, groups to target, and component costs can increase the likelihood that interventions will be highly cost-effective or even cost-saving."
Thanks for the reminder that a bit more humility and a lot less hyperbole are needed concerning prevention.
It's now clear: I lack the patience to await the full four parts of a powerful new series of posts on Junk Food Science before sharing it with Salt Sensibilty readers. They're too good to wait. They examine the subject: “Paradoxes – Compel us to think.” So far, two posts: Part One and Part Two . Sandy Szwarc introduces the quest to “separate science from ideology” (phrase from JAMA ) as follows:
We may know, intellectually, that correlations can never show causation, but when a correlation seems to confirm a reason we believe, it’s very easy to find ourselves falling for the fallacy, anyway, and to not even consider other explanations. We may call our belief “common sense” or what “everyone knows,” without realizing that we’ve come to believe it simply because it’s all we ever hear. It may never even occur to us to question an axiom — especially if we never hear about the evidence which contradicts or disproves it.
Her primary focus remains obesity as we may remember since I've often blogged on her relevant posts. Nevertheless, many of the observations pertain equally to the salt and health controversy. She notes that “The obesity paradox wouldn’t be a paradox at all, for example, if the public had been hearing objective reports of medical research all along.” How true for salt. I've just been participating in an online discussion at Toronto's Globe and Mail that well illustrates the pervasive retreat to unexamined acceptance of asserted medical “truths.”
Understanding the limitations of the scientific method employed is crucial. She observes:
(E)pidemiology has become a vehicle to find associations between every aspect of our everyday lives or our physical features and risks for some feared disease. And it’s being misused to convince us that our diets and lifestyles or appearances are the cause of ill-health. Blame, guilt and fear are the bread and butter of health marketing. That’s why carefully controlled epidemiological studies that find no link — those null studies that rarely get reported — are especially valuable. If there’s not even a strong link between two variables, then a variable can’t possibly have a causal role. Null studies tell credible scientists, and should tell us, to move on and stop worrying about that.
Among the reasons all this matters, she offers as an example the question of exercise. “Everyone” knows exercise is good for us. I feel better when I'm in shape and when I exercise. Of course. Common sense. But there are always unintended consequences. In this case, she provides data from the Centers for Disease Control and Prevention (CDC) that, next to the common cold, sports and exercise injuries are the leading cause of doctor's visits. That doesn't mean: don't exercise. It means, weigh the evidence ( and, probably, engage moderately). Federal data confirm that 488 million work days are impaired by sports injuries and that baby boomer sports injuries cost $18.7 billion in 1998.
Bottom line, she concludes in Part One:
Scientists understand the importance of testing hypotheses about causes and effects — and balancing overall benefits over risks — using carefully designed randomized, controlled clinical trials and measuring hard clinical outcomes. Yet, every randomized, controlled clinical trial of “healthy lifestyles,” as popularly defined, has failed to significantly reduce premature deaths from all causes or to prevent chronic diseases of old age.
Part Two continues to bust obesity-related myths, in this case: that obese individuals have worse health outcomes. “Everyone” believes that, too. Common sense. She offers the Helsinki Businessmen Study as a confounding input. The conclusion:
The only statistically significant inverse correlations to the men’s BMIs were with diabetes and hypertension — but they didn’t affect the men’s mortality rates, perhaps because, as we’ve seen, heavier people with both conditions have lower health complications compared to slender people with those conditions. Other popular myths weren’t supported in this study, which also won’t surprise regular readers who’ve followed the research. The men who gained weight as they aged and those who lost weight to achieve a normal weight had identical rates of developing diabetes, and the same cholesterol levels and blood pressures , as they aged.
Once again, the conclusions track closely with how the salt and health debate was sidetracked into the blind alley of a solitary focus on blood pressure. See the parallel:
Time and again in randomized clinical trials of pharmaceuticals and other medical interventions, we’ve seen the importance of examining confirmed clinical endpoints — with all-cause mortality the most important — rather than surrogate endpoints. Not understanding risk factors and believing that these surrogate health indices are measures of health and future disease has been the greatest way the public been led to believe that weight loss is beneficial, even when it’s not supported in well controlled studies looking at actual clinical outcomes and mortality.
The only difference here is that there have not been repeated RCTs on salt reduction – only a dozen or so observational studies, though they have suggested our uncritical acceptance of the salt hypothesis has been erroneous. It matters not only because we waste time, effort and expense pursuing the wrong remedy, but because the fallacious intervention can actually create health risks. Take the obesity case again:
German epidemiologists, examining 13,362 middle-aged adult men and women in the European Prospective Investigation into Cancer and Nutrition-Potsdam Study, for example, found that fat people who had normal blood pressures prior to weight loss had a nearly 7-fold increased risk of developing essential hypertension during the following two years after weight loss, and those whose weight yo-yoed had a 4.29-fold increase in hypertension.
And, referencing Dr. Thorkild Sorensen at the Institute of Preventive Medicine in Copenhagen from an article in the International Journal of Obesity:
It’s been argued, he summarized, that weight loss does not equal improvement in health and longevity, that staying fat is safer than weight fluctuations, and dieting has negative psychological effects. “In summary, we still do not have conclusive evidence that weight loss has overall beneficial effects.”
She wraps up Part Two with a warning:
The possible healthfulness of natural weight gain with aging, however, is a paradoxical idea in popular media. People may never think to question their beliefs about the deadliness of fat and benefits of weight loss when they never hear anything different.
The importance of research finding seeming paradoxes is that it make us think, question and not be afraid to learn where the evidence might really take us.
Echoes of the salt and health debate. We need to change our paradigm and become evidence-based.
Prominent food scientists, including a member of the federal Dietary Guidelines Advisory Commmittee (DGAC), reported to the IFT last week on the process underway to revise the Guidelines. Dr. Fergus Clydedale of UMass, the lone food scientist on the 2005 DGAC, and Dr. Roger Clemens of USC, the token food scientist on the 2010 DGAC, painted a bleak picture of the use of science and understanding of food technology. Clemens noted he has been relegated to food safety issues and, implied, kept at a distance from nutrition issues.
Clydesdale and Clemens addressed the IFT session on "The evolution of dietary guidance: Lessons learned and new frontiers."
Covering the session, BakingBusiness.com quoted Clydesdale saying: "A food scientist should not be regulated to just food safety on the Dietary Guidelines, and there should be more than one." The report continued:
Dr. Clydesdale said technology has helped society in many areas. He said he doubted people would like to go back to using typewriters or that teachers would like to go back to using chalkboards.
"We’re not going to go back to 78 r.p.m.s (records)," he said.
Dr. Clydesdale said he wondered why people do not embrace technology in the food system. He said he wondered why people wanted to cook the way people did 100 years ago.
The Dietary Guidelines could use input on how food science technology may help meet the Guidelines goals, Dr. Clydesdale said.
We'd prefer an evidence-based approach rather than the DGAC's current expert opinion process. Apparently so do the experts.
A recent study in the American Journal of Clinical Nutrition by Fumiaki Imamura et al examined adherence to the 2005 Dietary Guidelines for Americans to determine how compliance related to coronary artery disease outcomes. Their conclusion: some Guidelines are more important than others.
In fact, they documented that the salt Guideline doesn't work at all. Women who had better overall quality diets actually were LESS compliant on the salt (reduction) Guideline. The lowest third in terms of Dietary Guidelines compliance consumed much less than the recommended 2,300 mg/day sodium while the upper two-thirds in terms of overall dietary compliance actually consumed 12% MORE SODIUM. (table 3).
Considered as a whole, the authors concluded:
No significant association was identified between the DGAI as a measure of diet consistent with the 2005 DGA and narrowing of coronary arteries after a mean 3.3 year follow-up period in post-menopausal women with established cornonary artery arthersclerosis.
The study found that "no womeno[of the 224 in the study] reported complete adherence to all dietary recommendations" consistent with other studies. On the other hand,
not all components have an equal weight in describing diet-disease relations....not all dietary recommendations are equally related to disease progression. Our findings highlight the need for the development of more sophisticated approaches to the assessment of dietary recommendations on disease progression and other chronic disease outcomes.
A former National Heart, Lung and Blood Institute employee, DebbieN, blogging on Slow Food Fast , showed her true colors earlier with her "Salt Rant" post. She has now opened a discussion about the science underlying her former agency's support for universal sodium reduction.
DebbieN's post "Misunderstanding Salt Research: Bon Appetit's Shamfeul 'Health Wise' column" yesterday doesn't fully avoid the name-calling and attempted intimidation that has characterized past attempts to suppress discussion of the science. She lashes out at John Hastings, author of a skeptical piece in Bon Appetit , noting that as "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 she at least continues through her rant to address some meaningful issues. Would that the Dietary Guidelines Advisory Committee did the same, but that's another post.
Yesterday, I posted comments on DebbieN's post, but her blog is moderated and she has not seen fit to approve my comments. Even without reading her original post, you can get the flavor of her representations. In my signed comment, here's what I said:
Your post provides so many "targets of opportunity."
John Hastings posed the right question: if an intervention modifies one of many risk factors but does not modify health risk (or even worsens that risk) then we should reconsider advice to follow that recommendation. But let me skip ahead first.
I am president of the Salt Institute. We do not "demonize salt moderation." We endorse moderate salt intake recommendations as were part of the Dietary Guidelines until 2000 when they abandoned "moderation" in favor of specific (lower) intake levels.
Studies of health outcomes of those lower levels show 20-37% greater cardiovascular mortality among those reporting they consume the lower, recommended levels -- these data from the editor-in-chief of the American Journal of Hypertension. See a discussion on our website at: http://www.saltinstitute.org/Issues-in-focus/Food-salt-health and http://www.saltinstitute.org/Articles-references/References-on-salt-issues/SI-references-on-issues/SI-references-on-food-salt-health-issues .
It is the proponents of "moderate" low-salt diets who are misleading the discussion by claiming that a 60% reduction in salt is "moderate." A 60% reduction is not only not "moderate" -- it is unsustainable in free-living subjects.
The health outcomes question CAN be studied. NHLBI has already proved the protocol -- the Trials of Hypertension Prevention -- only it measured the wrong outcome (BP not CV mortality).
The DASH Study you mention is very important for the blood pressure argument (but not for health outcomes). Its findings, however, are that for those with high blood pressure, the systolic BP fall on the DASH Diet was 11.4 mmHg. When hypertensive subjects were put on a diet with 60% less salt, their SBP declined 11.5 mmHg. Thus, the "DASH effect" is 11.4 mmHg and the "salt effect" is 0.1 mmHg.
I could go on, but read the website and, even better, read the referenced medical journal articles to better understand the scientific controversy that John Hastings had the courage to describe.
The Spring issue of Salt and Health (pdf 318.77 kB) is published The misuse of the word “toxic” by media, some medical doctors and CSPI is examined within the context of long standing accepted definitions and parameters of the term. Concrete examples are illustrated in regards to replacing a natural substance, sodium chloride, with complex industrial chemicals such as: 5-ribonucleaotides, L-lysine, L-arginine, lactates, mycosent, MSG and trehalose. This newsletter leaves the reader to more intelligently ponder what health implications of such a broad-based replacement of salt with an arsenal of untested synthetic chemical products could possibly do to an unsuspecting population.
An article in Politico , a widely read DC paper, recently warned that President Obama and Congress are ramping up to impose a new era of public health activism unlike anything ever seen.
Michael Jacobson of CSPI gushed about the opportunities presented by this president, saying, “He has expressed more interest in preventing diseases and promoting health than any previous president. It is not a breath of fresh air. It is a tornado…This is really a rare opportunity to make progress on so many issues.” Jacobson’s favorite issue appears to be population-wide salt reduction.
According to Politico the president is “filling top posts at Health and Human Services with officials who, in their previous jobs, outlawed trans fats, banned public smoking or required restaurants to provide a calorie count with that slice of banana cream pie.”
In fact, many people were nervous after former NYC Public Health Commissioner Thomas Frieden was named director of the CDC. Frieden led the charge against trans fats, soft drinks and salt in the city. And Joshua Sharfstein, a new deputy commissioner at the FDA, created a Salt Task Force to study the “impact of excessive salt intake” in Baltimore, ignoring the scientific data which debunks the premise of population-wide salt reduction.
This doesn’t clearly divide along partisan lines. Some conservative members of Congress want to prohibit “junk food” under the federal food stamp program. While SI actively promotes a quality diet and certainly wouldn’t encourage anyone to eat “junk food” as a diet staple, we realize the slippery slope of bureaucrats deciding what is and is not junk food.
According to the Center for Consumer Freedom: “Get ready, because the ‘nanny state on steroids’ is going national.”
We have previously reported on the growing importance of the hormone aldosterone in blogs Aldosterone I , Aldosterone II and Aldosterone III , in addition to a dedicated Salt and Health Newsletter . The most recent issue of the Annals of Internal Medicine echoes our sentiments on the subject. Authors J. R. Sowers, A. Whaley-Connell and M. Epstein write on the growing recognition of the role of aldosterone in the pathogenesis of metabolic syndrome, type II diabetes, resistant hypertension and associated cardiovascular and chronic kidney disease.
Available evidence appears to indicate that the quickest and most direct way to elevate aldosterone levels in the body is to cut your salt intake to the levels recommended in the Dietary Guidelines for American , i.e. the equivalent of 1500 – 2300 mg sodium per day. We can only hope that one day, the Dietary Guidelines Advisory Committee will acknowledge all the credible evidence in the scientific literature rather than only that which serves their salt reduction advocacy.
If you're not regularly reading the blog Junk Food Science , you're missing some good stuff. Today's post is another gem: "Seeing the evidence: tighter control of blood sugars in type 2 diabetics " isn't about salt, but as poet-philosopher George Santayana famously observed: "Those who cannot learn from history are doomed to repeat it." There's an important lesson here.
In this case, blogger Sandy Szwarc reviews a recent meta-analysis of the health outcomes of high quality trials of interventions more tightly controlling blood sugars . Forget for a moment the literature showing that low-salt diets increase insulin resistance , the point is the process of substituting well-publicized, lower quality studies as summarized by expert "consensus" for reliance on the available quality data. That is a pattern we've seen in the salt and health controversy as well. The blog's well worth reading, but, bottom line, Szwarc summarizes:
To this day, no sound clinical study has ever shown that treating type 2 diabetics to achieve even lower blood glucose levels provides added benefits that outweigh the harms. Treating a number that is a symptom of a disease doesn’t mean the disease process has been changed. Lowering health indices in elderly patients to match those of healthy 20 year olds doesn’t mean their risks will be lowered to those of 20-year olds again. And minimizing the risks associated with extremely high lab values doesn’t mean that “how low can you go” is better for patients.
Busy medical practitioners rely heavily on experts’ assessments of research findings, but those assessments are fraught with biases. As Dr. John P. Ioannidis, M.D., at the University of Ioannina School of Medicine in Ioannina, Greece, and with the Institute for Clinical Research and Health Policy Studies at Tufts-New England Medical Center, Tufts University School of Medicine in Boston, cautioned : “Empirical evidence on expert opinion shows that it is extremely unreliable.” As we also see time and again, the analyses and conclusions made by study authors and industry experts often differ from what the data actually shows. Bias doesn’t always come from financial conflicts, but can come simply from a belief in a popular scientific theory. It can lead even medical professionals to see only what supports a theory: confirmation bias .
Myths can take on lives of their own even in medicine unless we look objectively and carefully at the evidence. Only with unbiased discussions can we ever hope to turn evidence-based medicine into evidence-based medicine.
Pray for poetic philosophy -- and hard data.