As we blogged when we first learned of the U.S. Preventive Services Task Force's revised recommendations on frequency of mammograms , we wished USPSTF were as influential as media coverage suggested -- and not because we wanted to express an opinion on this recommendation. Rather, we wanted to endorse the process of evidence-based public health policy.

That was two or three forests worth of coverage ago, and most of the media accounts studiously avoid the real question: is there evidence to support the recommendation? Story after story deal with the outrage on the left about damage to women's empowerment or, conversely, on the right, questions about whether the reduced use of the procedure presages the rationing of medical care alleged integral to ObamaCare.

Dr. Gilbert Ross of the American Council for Science and Health has a healthier perspective.

“I don't think this issue is a gender-related one at all,” says Dr. Ross. “It certainly shouldn't be. Actually, the emerging recommendations for PSA screening for prostate cancer are very similar to these breast cancer recommendations. The authoritative bodies weighing in on PSA screening basically say don't do it unless there is some rationale for it in terms of specific risk factors, because the potential downsides outweigh the benefits. Of course, any kind of cancer screening is always an emotional issue. For women who want a more individualized risk estimate to help guide them in this decision, the NCI has a 'tool' for figuring out one's risk for breast cancer. Some women in a higher-risk category, besides getting more frequent mammograms, may also consider discussing with their doctors the potential benefits of taking a drug to reduce risk of breast cancer -- chemoprevention.

...“We believe that politicizing this issue does no one any good and contributes to confusion among women and their doctors,” says Dr. Ross. “In fact, this is an unusual instance when we agree with a New York Times editorial, calling for the mammography screening discussion to be completely severed from the ongoing healthcare reform debate.”

ACSH quotes Dr. Arthur Caplan,director of the Center for Bioethics at the University of Pennsylvania, added his weight to the argument for reason:

“In this case, the taskforce found that screening all women in their forties led to too many false positives and too much unnecessary follow-up testing for the number of lives it saved. They did not say that no lives were being saved. They said not as many as everyone thought. And not enough to justify asking every woman under fifty to get a mammogram every year...

“There is no reason to doubt the accuracy of the scientists' finding that evidence does not support routine mammography for most women under fifty. But there is every reason to doubt that the numbers they compiled will be sufficient to overturn a medical practice that carries so much ethical weight for women.”

Let's not get hung up on how we feel on this issue. Science is evolutionary. Evidence can improve over time. Let's follow the science, not the ideologues.

It has been but a few short days since the U.S. media heralded findings by the U.S. Preventive Service Task Force (USPSTF) that there is insufficient evidence to recommend that some women get regular mammograms. The press reported that the USPSTF is "influential" in setting federal policy. We responded that we only hoped it was true , but, sadly, that hadn't been our experience. The USPSTF has been a lonely voice insisting on quality science to guide policy.

We know nothing of the quality of the science on either side of the mammogram debate, but we do know that when the evidence-based recommendations of the USPSTF come up against political correctness, PC politics wins. That's been the case with the debate over dietary salt.

Thus, it was no surprise that the White House ducked. The NY Times reported that when "the task force recommendations stirred concern among women, and came under fire from lawmakers of both parties, the White House emphasized that they were not binding...."

That's the way the federal government has dealt with the salt debate: politics trumped science. The USPSTF found insufficient evidence to recommend a general reduction in salt intakes, but the powers-that-be blithely ignored this evidence-based conclusion and redoubled its efforts to achieve the impossible: substituting federal recommendations for human physiology. Read all about it .

"(E)xcessive salt restriction is as harmful as high salt in heart failure," concludes a study in the European Journal of Pharmacology . The Osaka, Japan-based research team demonstrated that for heart failure patients low-salt diets activate plasma aldosterone and the "increased plasma aldosterone level with strict salt restriction activated the mineralocorticoid receptor signaling in volume-overloaded condition, resulting in increased myocardial fibrosis."

In short, yet another study showing the risk of low-salt diets. The authors conclude:

A recent report showed that high sodium intake rather improved cardiac performance, induced peripheral vasodilatation, and suppressed the release of vasoconstrictor hormones in patients with compensated heart failure (Damgaard et al., 2006). Indeed, our findings suggest that salt depletion, which increases the plasma aldosterone level, must be avoided in addition to salt overload in the treatment of heart failure.

There was an interesting story on the front page in the print edition of today's Wall Street Journal with an eye-catching but gratuitously offensive and grossly inaccurate headline: "Maybe Mummy Should Have Laid Off the Salt." We had to respond :

There has been exactly one clinical trial of the effect of low-salt diets on cardiovascular morality and rehospitalization for congestive heart failure. That study confirmed observational studies and showed conclusively that low salt diets produced greater mortality. See the article in Clinical Science, "Normal-sodium diet compared with low-sodium diet in compensated congestive heart failure: is sodium an old enemy or a new friend? " It concludes: "The results of the present study show that a normal-sodium diet improves outcome, and sodiumdepletion has detrimental renal and neurohormonal effects with worse clinical outcome...."

So, perhaps the mummy should have used more salt during life -- as well as the salts used in the mummification process.

It's headline writers like this that are responsible for newspapers coming in dead last in terms of consumer confidence .

TheWashington Post just released a story that the U.S. Preventive Services Task Force has concluded that mammograms are unwise for younger women. Post reporter Rob Stein describes the USPSTF as "an influential federal task force" and "the federal panel that sets government policy on prevention."

We could only hope that his description was true. In fact, the USPSTF has been trying to steer the federal government away from "junk science" and towards "evidence-based" health interventions for years. This may be, as Stein sums up, a "radical change" in public health recommendations.

Perhaps now people will pay more attention to what the USPSTF concluded back in 2003 and maintains today: our present policy discouraging salt intake in the general population may be politically-correct, but it is a scientifically-flawed policy. The USPSTF has studied the question and found insufficient evidence to make a general recommendation for the public .

We'd all be better off if the US Prevention Services Task force was, indeed, the influential panel that sets government policy on prevention that the Post postulates.

William Grimes book Appetite City: A Culinary History of New York , reviews the City's rich ethnic heritage evolving out of humble beginnings as Nieuw Amsterdam. He cites the increasing popularity of "ethnic" dining as the City's greatest achievement as a "food city."

By ironic coincidence, the book appeared a year ago, when the City launched an initiative that would eviscerate the sale of ethnic foods in Big Apple grocery outlets and decimate ethnic dining in the city. The health department, basing its campaign more on political correctness than sound science, is trying to persuade grocers and restaurateurs to provide shoppers and diners only low-sodium versions of the foods they love. Imagine a low-salt salt bagel. How about a corned beef on rye or hot pastrami? No, can't have that, they're cured in saltwater. Choose your favorite ethnic cuisine and you'll find it impossible to enjoy without salt; it's the quintessential ingredient in ethnic foods.

Literally millions of immigrants entered the US through New York City and, for example, there are 3.3 million Italian-Americans in the New York metro area and extensive number who themselves or whose families emigrated from Greece or other Mediterranean countries -- whose diet is deemed the healthiest in the world (pdf 592.83 kB) . Even though newly-reelected, I doubt Mayor Bloomberg wants to tell them to turn their back on their ethnic culinary heritage -- or encourage them to dine in Hoboken, Hempstead or Yonkers.

At a Washington, D.C. panel hosted by the Pan American Health Organization (PAHO) November 3rd, panelists representing the International Council for the Control of Iodine Deficiency Disorders (ICCIDD), US Agency for International Development (US AID), Health Canada, PAHO, US Food and Drug Administration (FDA) and the International Life Sciences Institute (ILSI) affirmed unanimously that there is no conflict between the global campaign to iodize salt and efforts in many countries to moderate salt intake levels.

Representing ICCIDD Americas Regional Coordinator Eduardo Pretell, former minister of health from Peru, explained that as salt intake levels may vary, or as the iodine contribution of iodized salt changes within the overall diet, salt iodization programs have proved they can simply and easily adjust the level of iodine fortification. He emphasized the necessity of systematic monitoring of iodine sufficiency either through measuring the household use of iodized salt or, better, through regular population surveys of urinary iodine excretion.

Pretell also pointed out that there is no evidence that countries which iodize salt consume different amounts of salt from those that have inadequate iodization, nor has salt consumption changed when a country achieves salt iodization. He emphasized that special care must be taken to ensure adequate iodine intakes for pregnant and lactating women and educational efforts directed to these groups urging use of iodized salt as part of any population salt reduction effort.

He reminded the group that iodine deficiency is a perpetual threat for persons living in areas with iodine-deficient soils and that, for those areas, universal salt iodization is the consensus strategy to improve iodine nutrition because fortifying salt with iodine is the easiest and least expensive option.

Pretell’s comments were amplified by Dr. Omar Dary from US AID who spoke generally on micronutrient fortification, but chose virtually all his examples from salt iodization initiatives. Dary explained that salt is the ideal carrier for iodine and other vital nutrients because its intake is consistent and predictable. He warned that the U.S. is at risk of iodine deficiency, urged American food processors to use iodized salt and reiterated Dr. Pretell’s insistence that monitoring is the key to success in salt iodization.

The importance of Dr. Dary’s advocacy for food processors to use iodized salt was brought home by Dr. Eric Hentges, president of ILSI, who presented new data confirming that, in the U.S., about three-fourths of salt is consumed as part of processed foods (none of which is iodized).

The other speakers confined their remarks to advocacy of salt reduction, but all affirmed the importance of successful salt iodization.

House speaker Nancy Pelosi (D-CA) unveiled her version of healthcare reform at a highly-orchestrated news conference yesterday. Featured in coverage in the Washington Post was the fact that the event featured 50-pound bags of salt -- used to anchor the background staging for the outdoor event against gusty winds,

six 50-pound bags of salt -- ice-melting salt, to be specific -- placed on the bases of the six U.S. flags on the stage to keep them from toppling over in the wind and marring the event with unwanted visuals and ruinous metaphors.

The Post headlined the speaker's rollout: "Rally has a lot of salt, but little pep."

Who knew salt would get dragged into the healthcare debate?

Matthew Continetti's editorial, "The inevitability myth," in the November 2nd Weekly Standard asks: "Did the Democrats become Calvinists when we weren't looking?" Continetti discusses the Obama/Reid/Pelosi strategy to pass healthcare reform. They argue, he says, that passage is "inevitable" given the overwhelming partisan majorities on both sides of Capitol Hill. He notes "lately they've been talking a lot about predestination" and claim enactment is "foreordained."

Healthcare reform is a discussion for another forum. Some might find the same pattern for other issues like global warming or the electronic bombardment of those living under high-voltage transmission lines. As usual, I see a salt connection.

I was struck by the synergy of the Standard's construct with an observation noted here in the past: how salt reduction activists have been prying into citizen's lives and larders. We had in mind more the "fire and brimstone" Puritans seeking to affix the "Scarlet S" on the nutritionally/politically incorrect than the Puritans' Calvinist forebearers . But it's much the same.

Now that we think of it, the second strand of strategic embrace of predestination/foreordaination as a rhetorical tool would also characterize these salt nannies. While reasonable scientists find evidence of elevated risk for significant portions of the population with a one-size-fits-all salt reduction strategy and others find evidence that human's salt intake is a physiologic appetite not a choice that can be educated or regulated, these New Calvinists gloss over the scientific controversy and want to skip ahead to "implementation," churning up group endorsements to add momentum to their version of "the inevitability myth."

Science, like time, would seem to answer this myth. Over time, population salt intakes are unchanged. Moreover, it may not be due to sinful choices of salty foods nor the perfidy of food manufacturers who (take your choice) either stuff their products with hidden salt or make wild health claims that low-salt products have proven health benefits. Salt intake, the science now suggests, is the direct result of neural signals from the brain controlling an unconscious salt appetite. Some may see intelligent design. We think it's heavenly.

Pointing to recently published evidence that salt intakes are unchanged over decades and in a range above that recommended in the Dietary Guidelines for Americans and may, therefore, reflect physiological signals of need and not consumer behavior, the Salt Institute has renewed its call to abandon numeric targets for Americans' salt consumption.

In formal comments today to the Dietary Guidelines Advisory Committee (pdf 36.38 kB) , Richard L. Hanneman, president of the Salt Institute pointed out that the body's consistent physiological salt appetite has the perverse result of increasing caloric intake instead of curtailing dietary sodium.

The Institute called for further study and for replacing the numeric target in the 2005 Guidelines with a call for "moderation" as contained in Guidelines beginning in 1980 until 2000.

Sometimes when telling the truth isn't "politically correct," messages in the mainstream media receive short shrift. Elitism trumps the views of the "man on the street." We've seen it blatantly in coverage of the salt and health issue. But as Bobby Dylan famously sang "the times they are a-changin.'" Today's Times (London, UK) carried a story dismissing efforts to demonize salt intake ("Is salt really the devil's ingredient? "). No, concludes journalist Peta Bee, quoting the chief dietitian at London's St. Georges Hospital, Dr. Michael Alderman from the Albert Einstein College of Medicine and Dr. Paul Whelton of Loyola University.

While these experts weigh-in saying the scientific evidence against dietary salt has been over-interpreted and anti-salt campaigns overblown, the often missed story is found in the "Comments" that regular readers contribute. They may not be "informed" by the science, but they reflect well-earned experiences that offer practical tempering to elite PC opinion. Consider these:

• "I find it very annoying that I was forces to eat tasteless food throughout my childhood due to my bother's belief that salt is bad." -- Genevieve Wilkins
• "I have often wondered why salt licks were provided for animals. We are animals, aren't we?" -- alan burden
• "I have truly believed for many years that if the government says salt is bad fro us, in time the opposite would prove to be true...how much taxpayers' money is wasted on health propaganda campaigns." -- Nicholas Mayes
• "It's funny - my horse's vet tells me that adding salt to feed isn't a problem....Odd how it's so difference in humans - almost like it's just an excuse for the government to interfere and tell us all how to live our lives, isn't it?" - K Charlton
• "Nanny doesn't always know best." - Chris Palmer
• "Be extremely careful about the anti salt message. I cut out salt on this advice, then moved to a sub tropical country and became seriously ill, with low salt at least one of the causes." - Paul Flynn

There seems to be a bubbling up of resentment about dietary diktats that may make holding the line on the anti-salt message akin to the fall of the Berlin Wall -- its demise could be more sudden and complete than "intelligence" estimates.

A study released on-line this week in The Clinical Journal of the American Society of Nephrology indicates that physiology, not public policy, will determine a human’s daily sodium intake. This research likely represents a important step forward in light of past and current efforts by government agencies and government funded organizations to set progressively restrictive guidelines for salt intake among U.S. citizens.

The study, Can Dietary Sodium Intake be Modified by Public Policy? (David A. McCarron, Joel C. Geerling, Alexandra G. Kazaks, Judith S. Stern), analyzed existing research to determine whether sodium or salt intake follows a pattern consistent with a range set by the brain to protect normal function of organs such the heart and kidney. The analysis is based upon 19,151 subjects studied in 62 previously published surveys and reflects the differing ‘food environments’ of 33 countries. The data reported documents that humans have a habitual sodium intake in the range of 2800 to 4600 mg/day with an average of 3600 mg/day. Currently, the U.S. consumes an average of about 3,500 mg/day.

The Dietary Guidelines Advisory Committee of the U.S. Health and Human Services and the U.S. Department of Agriculture considers 2,300 mg/day sodium to be a healthy maximum almost 20% lower than the minimum intake observed in the 19,000-plus subjects reported in this first-time analysis. In spite of that reality, the Committee is in the midst of a review to determine whether that recommendation should be lowered even further. An Institute of Medicine Committee is also considering a strategy to reduce dietary sodium.

The Committees should heed this study as they consider wasting more time and energy on policies which are unlikely to make American citizens any healthier. Time spent on draconian recommendations on a single ingredient would be better spent encouraging a healthful overall diet rich in fruits, vegetables and whole grains. The Mediterranean diet is high in salt, yet the Mediterranean people are known for excellent cardiovascular health. A healthful overall diet, not a fixation on any single ingredient, is one of the secrets to maintaining good health.

See the Salt Institute's news release (pdf 29.80 kB) .

One of the joys of my commute is the opportunity to listen to stimulating recorded lectures as part of The Teaching Company's Great Courses series. I'm in the middle of part 2 of a course by Steven L. Goldman, Ph.D. on "Great Scientific Ideas That Changed the World."

Lecture 13 on "The birth of Modern Science" discusses the contribution of Francis Bacon, an Elizabethan Renaissance man who developed the modern experimental method. Bacon developed his new method to overcome what he considered the intellectual fallacies of his time which he called "idols" of which there were four: idols of the tribe, idols of the cave, idols of the marketplace and idols of the theater. An idol, in Bacon's terms, was a fascination or fixation without basis in fact and which interferes from acceptance of an accurate understanding of some phenomenon.

Consider how relevant these fallacies are to the current debate on salt and health.

Idols of the tribe are deceptive beliefs inherent in society; they are based on error because they interpret observed relationships through the eyes of (current) orthodox opinion.

Idols of the cave are errors rooted in personal experience and limited by that experience.

Idols of the marketplace are errors rooted in semantics; words conjure up conclusions so the use of improper descriptors induces misunderstanding.

Idols of the theater grow from sophistry, a body of opinion sustained and perpetuated by group acceptance and popularity, but based on false assumptions.

How do Bacon's "idols" relate to the ongoing controversy over salt?

Tribe -- the overwhelming popular majority accept fallacious reasoning that because salt and blood pressure are related and blood pressure and health outcomes are related, that lowering salt will improve health. The evidence shows the contrary.

Cave -- Blood pressure researchers can manipulate subjects' BP by varying salt intake; therefore, they reason that changing BP alone, by any means (and an easy "means" is changing salt intake) will produce better health. There is no evidence to support this conceit.

Marketplace -- It's too bad recently-deceased William Safire didn't address this point. Assertions of "excess dietary sodium" and conclusions that "we eat more salt than we need" are among the several sleights-of-hand employed by salt reduction activists. How do they know better than an individual's neural-hormonal system what is "too much" salt?

Theater -- There are several illustrations, but the easiest to see is the continued preoccupation with endorsement by "expert groups" of the policy recommendation to reduce dietary salt, all the while ignoring the lack of evidence of a health benefit.

We salute Francis Bacon for pioneering a modern scientific method. He would be right at home with his passionate advocacy in today's kerfuffel over dietary salt.

European "food companies guilty of misleading people with health claims" trumpets a headline in the October 2 issue of Medical News Today . The story reports the views of the UK-based activist group Which? quoting the group's chief policy advisor saying of an ongoing review of health claims by the European Food Safety Authority (EFSA):

A huge number of food products claim to have health benefits, but finally we are separating the wheat from the chaff. Incredibly, only a third of health claims looked at by EFSA could be backed up.
Clearly many food companies are exploiting people's interest in improving their health, often over-charging them for alleged health benefits which can't be proved.
On a more positive note, there are foods using proven health claims, so it's vital that industry acts responsibly when making claims, and that the Food Standards Agency ensures the removal of misleading products. Only then can people be confident that the health claims on items they buy are genuine.

Medical News Today reports that EFSA has assessed over 500 claims.
Among the claims supported by Which? and found acceptable by EFSA are claims that reduced sodium foods are healthy. Food companies offering these products are pleased to cooperate to say these foods are healthier for consumers.
Talk about misleading people! EFSA (and Which?) ignore two yawning data gaps that fatally undermine the argument for salt reduction:

1. There is no evidence that there is a net health benefit of reducing dietary salt (pdf 434.26 kB) (in fact, the single controlled trial of the health outcomes (pdf 802.65 kB) of salt reduction found a greater risk among those on low salt diets), and
2. There is no evidence that those who choose low-salt foods (with "healthy" labels) consume lower sodium diets -- the evidence suggests salt appetite is an autonomic physiological response (pdf 517.27 kB) to the body's need for salt.

So, Which?, if food manufacturers are misleading consumers for unsubstantiated claims that their low-salt foods are healthier, you're no better for criticizing them while endorsing the very basis on which their misleading claims are based. As Wikipedia explains, the original idiom about "the pot calling the kettle black " has an alternative, subtler interpretation from a century old poem that extends the critique beyond simple hypocrisy. The poem points out that the actual idiom is "The Pot Bottom Calling The Kettle Bottom Black" drawn from the fact that "the pot is sooty (being placed on a fire), while the kettle is clean and shiny (being placed on coals only), and hence when the pot accuses the kettle of being black, it is the pot’s own sooty reflection that it sees: the pot accuses the kettle of a fault that only the pot has, rather than one that they share." The observation that the root of the problem is that food companies are reflecting back the junk science of groups like EFSA and Which? properly assigns responsibility.
The poem found in "Maxwell's Elementary Grammar" school book, reads:
"Oho!' said the pot to the kettle;
"You are dirty and ugly and black!
Sure no one would think you were metal,
Except when you're given a crack."
"Not so! not so! kettle said to the pot;
"'Tis your own dirty image you see;
For I am so clean -without blemish or blot-
That your blackness is mirrored in me"

You've all heard about one-armed economists (on the one hand.....on the other hand....). So it's hardly news that economists do not agree with a basic premise of Obamacare, namely, that "prevention" will save money. We did a blog post back in June when Time magazine featured the issue. Proponents responded last week when the New York Academy of Medicine released its Compendium of Proven Community-based Prevention Programs .

New York City has, of course, been waging war on salt in the city for a couple years now, so it's ironic that salt reduction is a glaring omission in the prevention policy recommendations.