One reason MSM journalists are losing their audience is the open secret that much of what is reported as "news" comes pre-packaged in canned stories from various advocacy groups and advertisers. Add that to the herd instinct that produces "PC"-slanted reporting and it's not difficult to poke holes in what we read in the newspapers or see on TV.

Cyber-journalism has the opposite problem. Rather than lemming-like PC stories based on pooled source information like wire services, bloggers and Web authors come in all shapes and sizes of quality and credibility. Who to believe?

When it comes to making sense of the chaos of Internet health reporting, Google is trying to intervene -- to make money and, they hope, to help seekers of quality information pertaining to their precious personal health. Query: will this be another case where the surgery is successful, but the patient dies? Will the choices of the Google censors preserve the essence of scientific inquiry where competing ideas are bombarded with data that either confirms or destroys them? Or will the desire to "help" consumers understand the meaning of medical scholarship excise aberrant findings, leaving only politically-correct interpretations?

We share the concerns of Sandra Szwarc in Junkfoodscience.com :

Search engines have inordinate abilities to censor information by simply making it invisible to searches. It is not uncommon for key documents and papers that don't support government initiatives or special interest agendas to be buried and take extraordinary effort to hunt down, or to disappear from the internet altogether, something anyone who's been researching for any length of time quickly discovers...

Google has just announced that it has created a "Google Health Advisory Council." ... Says Google : "We want to help users make more empowered and informed healthcare decisions, and have been steadily developing our ability to make our search results more medically relevant and more helpful to users."

Screening out "irrelevant" and "unhelpful" information? That sounds like a euphemism for censorship. Look at every name on their new prestigious advisory panel and the interests they represent. Most will be familiar to Junkfood Science readers, as we've examined the soundness of their consumer information RAND Corp., the Cleveland Clinic, the AMA, Robert Wood Johnson Foundation, AARP, Kaiser Foundation Health Plan, Inc., California HealthCare Foundation, and others.

Despite all of the flaws and utter garbage on the net, it's still been the primary way for most people to break through the media groupthink to learn other viewpoints and sounder information. This development could be the beginnings of the world's biggest internet information firewall.

Substituting a Google censor for the rigor of true "evidence-based" analysis would be a clear step backwards. Search engines seeking access to the Chinese market, reportedly, have agreed to censor their search results. That's unfortunate for 1.3 billion Chinese and a disturbing parallel to the new Google Health Advisory Council. What we need in public health policy is more transparency and solid information, not greater opaqueness and opinion. As we blogged recently , the quality of the process is of paramount importance. We need to be able to "lift the hood and kick the tires " of new medical studies, not have a secret censor decide for us what's relevant and what's not.

It would be hard to find anyone or any group today making health policy recommendations who doesn't claim their conclusions are "evidence-based." But since recommendations vary considerably in some areas, such as whether there is a health benefit to reducing dietary sodium/salt, it should be important to all of us exactly how "evidence-based medicine" (EBM) works and how it fits into the overall process of producing health care or health policy decisions.

An interview in the June 19 issue of Health Affairs magazine illuminates the limits of EBM and the shadowy abuses of the term.

Junkfoodscience.com has taken the American Heart Association to task for the poor quality of its evidentiary review to support its lifestyle recommendations for women. Writing of the American Heart Association's Evidence-based Guidelines for Cardiovascular Disease Prevention in Women released in May, Sandy Szwarc:

Not one observational study was able to credibly support the AHA heart healthy eating recommendations for women to prevent heart disease or premature death. The only observational study specifically looking at Healthy Eating in accordance with our government's dietary guidelines found no benefit. And finally, the strongest evidence - an actual clinical trial of the heart healthy diet on the primary prevention of heart disease in women, that went on for more than 8 years - found it had no effect on heart disease. Reviews of clinical trials conducted on heart healthy programs to date have found them of doubtful effectiveness, with no effect on mortality. Our beliefs in healthy eating have gone far beyond well-founded advice to eat normally and enjoy a variety of foods in order to prevent deficiencies, fuel our bodies, and for pleasure; to beliefs in special powers of foods as medicines or poisons.

This review looked at the evidence being used to support "evidence-based" recommendations for a heart healthy diet. When we hear the term "evidence-based," most of us probably had a very different picture in our minds.

While the AHA calls for rigorous public policies to implement its preventive guidelines population-wide in order to "combat the pandemic of heart disease in women," how many politicians and healthcare professionals will have taken the time to look at the evidence behind these recommendations? But we will have, and can make a more informed choice about what we want to eat.

This article is the Szwarc's second. The first , published May 2, pointed out:

A major medical paper on primary heart disease prevention admitted that cardiovascular disease risk factors have proven useless for predicting heart disease among our population and that reducing risks factors doesn't translate into reduced clinical disease or fewer premature deaths.

Sounds like our complaints about self-proclaimed "evidence-based" labels need a truth-in-labeling watchdog.

The American Medical Association House of Delegates will gather later this month in Chicago, where it will consider a vast array of resolutions directing their lobbyists in Washington as well as advising their physician members throughout the country.

Resolution 611 deals with "Evidence-Based Policy Development" and would require

RESOLVED, That our American Medical Association House of Delegates resolutions should include, whenever possible or applicable, appropriate reference citations to facilitate independent review by delegates prior to policy development. (Directive to Take Action)

Great idea -- as far as it goes. But evidence-based public health is more than a platitude . Two problems: timing and content.

We can hope that the controversy generated when AMA approved an anti-salt resolution last year might be the genesis of this year's resolution to get serious about basing resolutions on evidence. Evidence-based considerations were missing-in-action last year. Opinion trumped facts. So the timing's bad; it puts the cart before the horse.

The content is also suspect. It's a tepid gesture that will allow any proposer to claim his or her resolution is "evidence-based" merely by including literature citations. That's even worse than what has been passed-off as "evidence-based" policy recommendations by the experts on the Dietary Guidelines Advisory Committee (DGAC). We had recommended the DGAC model their analysis on international "evidence-based" standards. They didn't. Just as everyone wants to be felt to be fair, honest, to say nothing of attractive, witty, etc., self-proclaiming these virtues can often be wildly misleading.

What is "evidence-based" health policy?

Let's give credit where it's due. Back in 1972 A.L. "Archie" Cochrane penned his pathbreaking book, Effectiveness and Efficiency: Random Reflections on Health Services. This is the original textbook on "evidence-based medicine", a term familiar to most doctors and other healthcare professionals today. Cochrane's classic text has had a profound influence on the practice of medicine and on the evaluation of medical interventions. He was the first to set out clearly the vital importance of randomized controlled trials (RCTs) in assessing the effectiveness of treatments, and his work led directly to the setting-up of the Cochrane Collaboration , now a world-wide endeavor dedicated to tracking down, evaluating and synthesizing RCTs in all areas of medicine .

In my reading on the subject, for a recommendation to be evidence-based it should be developed using a structured and rigorous methodology based on a pre-determined set of criteria for grading the strength of any proposed recommendation. Consideration would be limited, most likely, to evidence found in randomized controlled trials and comparative controlled trials identified and synthesized using methods defined by the Cochrane Collaboration. An expert panel should first define evidence of outcomes important to individual subjects and, in aggregate, to the population, by determining the required strength of the evidence considered valid for inclusion in the review. Then, in blinded fashion, the evidence should then be graded against those criteria. The Cochrane methodology is preferred as a means to minimize bias since it outlines an objective and systematic approach to literature search, study selection, data extraction and data synthesis. Anything short of this dilutes the meaning of "evidence-based." To call the AMA approach "evidence-based" is whistling past the park.

Cochrane's home base, Oxford University, hosts a Centre for Evidence-based Medicine which answers the question "What is EBM? by extracting from an editorial in the British Medical Journal back in 1996:

Evidence-Based Medicine, whose philosophical origins extend back to mid-19th century Paris and earlier, remains a hot topic for clinicians, public health practitioners, purchasers, planners, and the public. There are now frequent workshops in how to practice and teach it; undergraduate and post-graduate training programmes are incorporating it (or pondering how to do so); British centres for evidence-based practice have been established or planned in adult medicine, child health, surgery, pathology, pharmacotherapy, nursing, general practice, and dentistry; the Cochrane Collaboration and the York Centre for Review and Dissemination in York are providing systematic reviews of the effects of health care; new evidence-based practice journals are being launched; and it has become a common topic in the lay media. But enthusiasm has been mixed with some negative reaction. Criticism has ranged from evidence-based medicine being old-hat to it being a dangerous innovation, perpetrated by the arrogant to serve cost-cutters and suppress clinical freedom. As evidence-based medicine continues to evolve and adapt, now is a useful time to refine the discussion of what it is and what it is not.

Evidence-based medicine is the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence-based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research. By individual clinical expertise we mean the proficiency and judgement that individual clinicians acquire through clinical experience and clinical practice. Increased expertise is reflected in many ways, but especially in more effective and efficient diagnosis and in the more thoughtful identification and compassionate use of individual patients' predicaments, rights, and preferences in making clinical decisi ons about their care. By best available external clinical evidence we mean clinically relevant research, often from the basic sciences of medicine, but especially from patient centred clinical research into the accuracy and precision of diagnostic tests (including the clinical examination), the power of prognostic markers, and the efficacy and safety of therapeutic, rehabilitative, and preventive regimens. External clinical evidence both invalidates previously accepted diagnostic tests and treatments and replaces them with new ones that are more powerful, more accurate, more efficacious, and safer.

Good doctors use both individual clinical expertise and the best available external evidence, and neither alone is enough. Without clinical expertise, practice risks becoming tyrannised by evidence, for even excellent external evidence may be inapplicabl e to or inappropriate for an individual patient. Without current best evidence, practice risks becoming rapidly out of date, to the detriment of patients.

This description of what evidence-based medicine is helps clarify what evidence-based medicine is not. Evidence-based medicine is neither old-hat nor impossible to practice. The argument that everyone already is doing it falls before evidence of striking variations in both the integration of patient values into our clinical behaviour and in the rates with which clinicians provide interventions to their patients. The difficulties that clinicians face in keeping abreast of all the medical advances reported in primary journals are obvious from a comparison of the time required for reading (for general medicine, enough to examine 19 articles per day, 365 days pe r year) with the time available (well under an hour per week by British medical consultants, even on self-reports.

The argument that evidence-based medicine can be conducted only from ivory towers and armchairs is refuted by audits in the front lines of clinical care where at least some inpatient clinical teams in general medicine, psych iatry (JR Geddes, et al, Royal College of Psychiatrists winter meeting, January 1996), and surgery (P McCulloch, personal communication) have provided evidence-based care to the vast majority of their patients. Such studies show that busy clinicians who devote their scarce reading time to selective, efficient, patient-driven searching, appraisal and incorporation of the best available evidence can practice evidence-based medicine.

Evidence-based medicine is not "cook-book" medicine. Because it requires a bottom-up approach that integrates the best external evidence with individual clinical expertise and patient-choice, it cannot result in slavish, cook-book approaches to individual patient care. External clinical evidence can inform, but can never replace, individual clinical expertise, and it is this expertise that decides whether the external evidence applies to the individual patient at all and, if so, how it should be integrated into a clinical decision. Similarly, any external guideline must be integrated with individual clinical expertise in deciding whether and how it matches the patient's clinical state, predicament, and preferences, and thus whether it should be applied. Clinicians who fear top-down cook-books will find the advocates of evidence-based medicine joining them at the barricades.

Evidence-based medicine is not cost-cutting medicine. Some fear that evidence-based medicine will be hijacked by purchasers and managers to cut the costs of health care. This would not only be a misuse of evidence-based medicine but suggests a fundamental misunderstanding of its financial consequences. Doctors practising evidence-based medicine will identify and apply the most efficacious interventions to maximise the quality and quantity of life for individual patients; this may raise rather than lower the cost of their care.

Evidence-based medicine is not restricted to randomised trials and meta-analyses. It involves tracking down the best external evidence with which to answer our clinical questions. To find out about the accuracy of a diagnostic test, we need to find proper cross-sectional studies of patients clinically suspected of harbouring the relevant disorder, not a randomised trial. For a question about prognosis, we need proper follow-up studies of patients assembled at a uniform, early point in the clinical course of their disease. And sometimes the evidence we need will come from the basic sciences such as genetics or immunology. It is when asking questions about therapy that we should try to avoid the non-experimental approaches, since these routinely lead to false-positive conclusions about efficacy. Because the randomised trial, and especially the systematic review of several randomised trials, is so much more likely to inform us and so much less likely to mislead us, it has become the "gold standard" for judging whether a treatment does more good than harm. However, some questions about therapy do not require randomised trials (successful interventions for otherwise fatal conditions) or cannot wait for the trials to be conducted. And if no randomised trial has been carried out for our patient's predicament, we follow the trail to the next best external evidence and work from there.

Despite its ancient origins, evidence-based medicine remains a relatively young discipline whose positive impacts are just beginning to be validated, and it will continue to evolve. This evolution will be enhanced as seve ral undergraduate, post-graduate, and continuing medical education programmes adopt and adapt it to their learners' needs. These programmes, and their evaluation, will provide further information and understanding about what evidence-based medicine is, and what it is not.

Authors:

David L. Sackett, Professor, NHS Research and Development Centre for Evidence-Based Medicine, Oxford. William M. C. Rosenberg, Clinical Tutor in Medicine, Nuffield Department of Clinical Medicine, Oxford. J. A. Muir Gray, Director of Research and Development, Anglia and Oxford Regional Health Auhtority, Milton Keynes R. Brian Haynes, Professor of Medicine and Clinical Epidemiology, McMaster University Hamilton, Canada W. Scott Richardson, Rochester, USA

The AMA does not welcome "outside" comments (hence this blog), but AMA members may wish to share their thoughts on how their association may be over-reaching by claiming an evidence-based procedure. The contact is Susan L. Hubbell, MD, chair, Reference Committee F, and, again, the proposal is Resolution 611 .

So says Elizabeth Bromstein writing in NOW Magazine (Toronto). "I don't think anybody ever had a heart attack from drinking too much mineral water or vegetable juice," she says, noting that while some think we ingest too much salt, "others say the warnings are way out of whack." So she did her own research and reported:

What the experts say

"Around 1900 we had an average sodium intake of 200 mg a day, and now we have an average intake of 5,000 mg. Sodium has to work with potassium and magnesium, and while our salt intake has increased, our potassium and magnesium intake has gone down. The increase is mostly due to processed foods, but if you eat a diet low in processed foods and high in fruits and vegetables, your salt level is probably fine. Your potassium and magnesium are probably fine as well, and you can add table salt to foods."

AILEEN BURFORD MASON, immunologist and nutritional consultant, Toronto

"In Canada, 25 per cent of people have hypertension, and one in three would not have it if his or her sodium intake were lower. Processors and restaurants are responsible for 80 per cent of our salt intake. We add 10 per cent ourselves, and 10 per cent occurs naturally in food. If we asked restaurants to cut the amount, we'd see a dramatic improvement. Hypertension causes two-thirds of strokes, one-half of all cases of heart failure and one-quarter of all cases of kidney failure and heart attack. Hypertension is one of the major drivers of dementia. There are more effective ways of reducing hypertension than reducing salt, like increasing physical activity, losing weight, getting enough soluble fibre and eating low-fat dairy products."

NORMAN CAMPBELL, professor of medicine, Libin Cardiovascular Institute, University of Calgary

"We know salt is associated with blood pressure, so we concluded that anything we could do to reduce blood pressure would achieve the same risk profile of lower-risk populations, but that hasn't turned out to be true. Some studies even suggest that there may be an increased risk for cardiovascular disease with a reduced salt diet, since it increases insulin resistance and can affect plasma renin activity. Until 12 years ago, we did not look at the net effects [of reducing salt] and only looked at blood pressure. Even then, about a third of the population responded [positively] to salt restriction. What we need is a five-year controlled intervention trial."

RICHARD L. HANNEMAN, president, Salt Institute, Alexandria, Virginia

"Salt is one of those essential elements we need in moderation. There are people who are salt-sensitive. Your intake should depend on your sensitivity level. Salt helps stimulate the kidneys, helps promote fluid metabolism and has a moistening effect. A little bit [taken internally] is good if your skin is very dry. It also has a mild detoxifying effect. In Chinese medicine it is also known as a s oftener for hardened lymph nodes, glands or muscles. It gently promotes bowel regularity. Most importantly, it needs to be kept in balance with potassium. Aside from causing hypertension, too much salt can interfere with calcium absorption and lead to poor bone health. If you have PMS and bloating, it's important to reduce your salt intake as well."

DU LA, naturopath, Toronto

Not to pick a quarrel with experts (especially since Ms. Bromstein kindly denotes me one), but Ms. Mason is just flat-out wrong about salt intakes increasing from 200 mg/day to 5,000 mg/day over the past century. In fact, sodium intakes are virtually the same at about 3,500 mg/day. Dr. Campbell employs the classically flawed extrapolation of blood pressure to heath outcomes; a model rejected by direct health outcomes studies. And the solution to the "bloating" probem identified by Mr. Du is to drink more water, not consume less salt.

That said, the experts also made some important points: Ms. Mason points out any health problem owes to the imbalance of sodium on one side and potassium and magnesium on the other, advising to eat more fruits and vegetables so that your "potassium and magnesiium are probably fine as well and you can add table salt to foods." Balance and moderation: good advice. Though limiting his comments to blood pressure and not health outcomes, Dr. Campbell concedes the same point: "There are more effective ways of reducing hypertension than reducing salt, like increasing physical activity, losing weight, getting enough soluble fibre and eating low-fat dairy products." And Mr. Du agrees: "Salt is one of those essential elements we need in moderation. ... Most importantly, it needs to be kept in balance with potassium."

Thank you, Ms. Bromstein for your reasoned advice. For more on the Salt Institute perspective see our summary and reference citations .

Yesterday in Paris, France, Dr. Tilman Drueke conducted a forum featuring three other scientific experts on various aspects of salt and health. The event was organized by EuSalt, the trade association of European salt producers. An audience of salt producers and news reporters heard presentations by Drueke of Necker Hospital, Paris; Dr. Jens Titze from Erlangen, Germany; Dr. David A. McCarron from the U.S.; and Niels Graudal from Denmark.

Dr. Drueke noted that scientific investigation of the relationship of dietary salt and health outcomes has a distinct "political aspect" and represents an "ongoing hot debate on the pros and cons of a generalized salt restriction." He referenced Gary Taubes' article in Science: "The (Political) Science of Salt ." Drueke declared:

In any case, high blood pressure is nothing more than a surrogate marker of outcome. What is really important is outcome itself. Surprisingly, the medical community has started only recently to examine this issue, namely a possible relationship between salt intake and cardiovascular or all-cause mortality. No prospective randomized controlled trials have been done to address this question. Only observational studies are available and their results led to contradictory conclusions."

He postulated that "the solution...may reside in the notion of salt sensitivity." Salt sensitivity, he explained differs from person to person and for a given person can vary from time to time based on other factors, including diet. He concluded:

"...the main focus on salt restriction is erroneous. In addition, although reducing sodium intake has many effects, either by its own or in interaction with other dietary components, we know nothing about their unintended consequences on human health."

Dr. Titze introduced data that completely call into question the evidence on sodium intakes over the past century. It has been well-accepted, he recounted, that the "gold standard" surrogate for dietary sodium intake is a 24-hour urine specimen, based on the well-understood notion that the body has a fixed store of sodium and daily additions are excreted to maintain sodium balance. He continued:

"Startling data from recent long-term balance studies, where healthy human subjects accumulated large amounts on Na+ without significant changes in their body water content, have challenged this traditional view....Subsequent experiments in animals have confirmed tht large amounts of Na+ can be accumulated without commensurate water retention in the organism."

This, in turn, led to the hypothesis that the skin and skeletal muscle could contain reservoirs of sodium which totally confound previously accepted measures of dietary sodium intake and that "...these Na+ reservoirs might 'buffer' the relationship betwen total body Na+ excess and blood pressure. This hypothesis has been supported in experiments...." This research clearly has major scientific and public health nutrition policy implications.

Dr. McCarron emphasized that evidence shows "that dietary patterns rather than salt should be the focus of public health nutritional recommendations to reduce BP" (blood pressure). He pointed out that the two DASH (Dietary Approaches to Stop Hypertension) studies showed the importance to blood pressure of diets rich in calcium, magnesium and potassium (fruits, vegetables and dairy products), and that the Trials of Hypertension Prevention showed that the blood pressure lowering effect even of significant salt reduction disappears over three years. He noted that

"the intoduction of fruits, vegetables and low-fat dairy (DASH diet) essentially eliminated salt sensitivity even in hypertensive individuals....the DASH-Sodium investigators (and) government agencies, without justification, have used this trial to argue for universal sodium restriction, regardless of blood pressure status....This position has occurred even though numerous meta-analyses and the results of the DASH-Sodium trial itself do not support the conclusions that sodium restriction is effective for normal individuals or for most hypertensive subjects."

Dr. McCarron then warned:

Sodium restriction has a variety of effects beyond blood pressure on other risk factors for CVD. These include weight, insulin resistance, angiotensin II, the sympathetic nervous system, diet quality and physical activity. For each of these risk factors, the preponderance of the evidence indicates that moderate or greater sodium restriction is associated with an adverse impact. Weight control is impaired, insulin resistance increases, angiotensin II levels are raised, sympathetic activity is increase, diet qualityis harder to achive, and maximal exercise capacity may be impaired. None are improved with sodium restriction. Thus, while BP may be decreased in 30-40% of individuals with sodium restriction, the impact on these other CVD risk factors in both salt-sensitive and salt-resistant individuals may offset any potential benefit."

Concluding the Forum, Dr. Graudal reviewed the mass of medical literature for which he has published one of the foremost meta-analyses. He declared:

"The fact is that today supporters of sodium reduction and sceptics do not diasgree about the effect size (BP reduction on reduced salt diets). Furthermore, they agree that sodium reduction can be useful in individuals with elevated BP. The controversial question is: Does an effect of 1-2 mm Hg in normotensive persons justify a general recommendation of sodium reduction in the whole population? The sceptics think not. The supporters think that any small decrease in BP will result inan improved survival and less morbidity. However a recent meta-analysis of the effect anti-hypertensive beta-blockers indicates that this is not necessarily the case....You must have proof and this does not exist, as also shown by a recent review of epidemiological studies which like teh clinical trials could not relate dietary sodium to to cardiovascular disease and death."

Thanks to the organizers of this valuable Forum.

As if we needed further reminder that just because "experts" eyeballed a published study it's methods and conclusions must validate its authors' conclusions, comes an outstanding editorial by Dr. Elizabeth Whelan, president of the American Council for Science and Health in TSC Daily on "From Peer Review to Fear Review ."

Although the article recounts why a recent cancer study is "junk science," the principles have played out in studies involving salt and health as well.

The lesson: look at the quality of the science, not the authors' (or headline-writers') conclusions and don't allow the pedigree of the investigators to give them a free pass to tout their policy preferences. Back to basics!

Research presented this week at the American Society of Hypertension 2007 Scientific Sessions in Chicago, has shown that fewer and fewer people are following the DASH diet. Even though more people are aware of hypertension, investigator Dr Phillip Mellen said the dietary quality of hypertensive adults has deteriorated.

Speculating as to why fewer patients are following the recommendations, Mellen noted that many physicians do not feel adequately trained to implement the DASH diet. More likely, however, is the fact that dietary counseling takes time, and clinicians are still not reimbursed for their counseling labors. "It might be easier to give a prescription than to address root causes," said Mellen.

Dr. Mellen is correct, but he neglects to expand on the role of the American Medical Association on the issue. Instead of prescribing medication as physicians do, the AMA has prescribed the magic bullet of salt reduction as the answer to hypertension.

Of course, the AMA will agree that the DASH diet is useful, but their high priority target is salt reduction. As a consequence, recommendations from the AMA to consume the DASH diet takes a back seat - a distant back seat to salt reduction .

While salt reduction may reduce the single cardiovascular risk factor of hypertension in some sensitive individuals, consumption of the DASH diet reduces all 10 major cardiovascular disease risk factors in all individuals. If a prestigious organization such as the AMA would spend more time and money on promoting the DASH diet, a number of things would occur. Physicians, whose knowledge of dietetics and nutrition is generally wanting, may choose to learn more about balanced diets and may be influenced to spend more time telling their patients about the overall benefits of the DASH diet.

Positive open support for the DASH diet from the AMA may also influence the food industry to develop new products that will allow consumers to consume the 5 - 10 servings of fruits and vegetables recommended each day. The new fusion juices (fruit and vegetable combined) are a perfect example. One glass is the tasty equivalent to two servings and a lot easier to take at breakfast than a bowl full of chopped kale!

With the proper emphasis on balanced diet, the medical community can help millions achieve better health.

As highlighted in one of our previous blogs , the anti-salt campaign being waged in the U.K. by the Food Standards Agency (FSA), has resulted in the removal of saltshakers from school lunchrooms. Telegraph correspondent Paul Eastham reported that this has resulted in students totally avoiding their vegetables while in school. By blindly following the "avoid salt at all costs" mantra, the FSA has effectively prevented young students from enjoying the benefits of vegetable consumption during the school day.

A far more rational approach was advocated by the Alliance for a Healthier Generation, the coalition between Bill Clinton and the American Heart Association. They made it clear that increased salt consumption was warranted whenever consuming foods that delivered essential nutrients, if the salt made these foods more palatable. They based their recommendation on the overall benefit/risk balance.

In order to reduce the level of rhetoric and to begin bringing scientifically-derived data to the issue, the Salt Institute, together with the Center for Innovative Technologies and the Department of Food Science and Technology of Ohio State University organized a series of formal taste panels to determine the impact of different levels of salt on the palatability and acceptability of cruciferous vegetables.

Sample preparation

Broccoli was chosen as the first test vegetable. Two levels of salt, high and medium/low, as well as zero salt were added to cooked broccoli and the participants were asked to rate their preferences. Computerized sensory evaluation software by Compusense was used to evaluate all responses and compile the resulting analysis. Naturally, participants were not informed which samples contained which levels of salt and all sample numbers were randomly generated

This is serious work

The first trial involved 88 students, ranging in age from 9 - 13 years. The students were fully briefed on the procedures and enthusiastically took part in the trials.

A good rinse between samples

The result was a virtual tie in preference between the high and medium/low levels of salt addition, with the zero salt a very distant third. Cruciferous vegetables are very nutritious, but are known to contain bitter components which youngsters are sensitive to. However, a small amount of salt makes these vegetables (together with their nutrients) highly acceptable.

Which one tastes best?

This study, together with future trial will be published in detail in the near future

Josephine Thompson correspondent for the South Wales Echo , asks the one question everyone should be asking. If we are eating too much salt, then why are we living longer? A simple question that deserves an honest answer.

She also goes on to say that she tried the modern version of ready to eat foods (presumably reduced-salt) and "never tasted anything so bland in all her life". A simple observation that food manufacturers should take heed of. They would be far better off listening to the opinions of their paying customers than to agenda-driven activists and civil servants.

A short, honest article from someone unafraid to speak her mind.

Should dietary advice be dispensed nutrient-by-nutrient or in terms of foods being part of dietary patterns? Though many government and advocacy dietary recommendations are expressed in terms of nutrients, the Salt Institute argues for "dietary patterns" in its Spring 2007 Salt and Health newsletter, published today. The Institute explains:

Decades of research in nutritional epidemiology as well as dietary intervention clinical studies have focused on assessing or manipulating the intake of a specific dietary component to determine its role in the development or treatment of a given disease or disorder. Despite the exhaustive effort that has invested in this field of research, it has remained mired in inconsistent and often conflicting results, confusion on the part of the general public, and lack of consensus among the experts.

The public is skeptical of seeming inconsistency between "scientific" studies, the article continues, but there is often a logical explanation.

Nutrients are not ingested in isolation, but as combined constituents of a total diet. Our diets consist of a variety of foods with complex assortments of nutrients and other ingredients, many of which may act on one another synergistically or antagonistically. When the intake of one nutrient is manipulated for study, increased or decreased, the intake and interactions of other components in the diet are likely to be altered.

Properly appreciated, dietary patterns should be the focus of dietary recommendations, the Institute argues, If that happens

We may well be approaching the time when nutrition scientists, policy makers, and the American public can set aside their differences and their skepticism, and sit down together over a meal they can all agree is healthy.

The World Health Organization (WHO) is concerned about the scientific basis of its health recommendations (a concern with WHO we've been vocal in expressing as well). In 2003, the WHO Cabinet recognized the need for process changes to improve the scientific evidence foundation for its policies. Its report appears in today's edition of The Lancet (free registration required).

Authors Andrew Oxman et al note:

WHO's regulations emphasise the role of expert opinion in the development of recommendations. In the 56 years since these regulations were initially developed, research has highlighted the limitations of expert opinion, which can differ both across subgroups and from the opinions of those who will have to live with the consequences. Experts have also been known to use non-systematic methods when they review research, which frequently results in recommendations that do not reflect systematic summaries of the best available evidence.

That's certainly the case in WHO's Report 916 , coincidentally generated in 2003, which selectively cited the literature and reached historically-extreme recommendations regarding dietary salt.

Oxman continues:

Evidence-informed dissemination and implementation strategies are increasingly recognised as a core part of the business of development recommendations.

Unfortunately, the authors found that WHO "almost always" employed the subjective expert committee approach in preference to the systematic review of published evidence. "The guidelines for developing WHO guidelines do not seem to be closely followed...," the report states, neutrally. In fact, they continue:

Although the WHO guideline recommendations are consistent with those developed by other organisations, the actual processes used to develop recommendations at WHO seem to be less rigorous than those of others. None of the directors [note: 23 WHO department directors were interviewed for the research] reported using the guidelines for WHO guidelines and only two reported plans to use them. Few directors reported using processes that were consistent with the guidelines.

Our experience with WHO in Geneva is that developing the nutrition guideline was virtually complete when the staff selected its expert panel; everything subsequent was a sham. With unfortunate results.

In the area of salt, evidence-based organizations like the Cochrane Collaboration and the US Preventive Services Task Force (HHS) have done systematic reviews of the health benefit potential of reducing dietary salt and both agree evidence is lacking to support such an intervention.

Everyone registering an opinion on dietary recommendations claims their advice is "evidence-based," but -- as this WHO study illustrates -- the truth is that governments and advocacy organizations routinely use the lowest form of evidence, expert committees, to formulate recommendations. It brings to mind a verse from the New Testament in the Bible (Matt. 15:8), "This people draweth nigh unto me with their mouth, and honoureth me with their lips; but their heart is far from me."

We need to do more to elevate the place of true evidence-based decision-making in public health nutrition policy through such means as ensuring effective enforcement of the U.S. federal Data Quality Act and opening the rich databases created for federally-funded studies to independent analysis by qualified experts. But, as the authors of this study lamented concerning WHO, achieving this broader objective "will require leadership."

Journalists swarmed Salt Institute technical director Mort Satin after his presentation this week at the Salt Expo staged in Naples, Italy. This first-ever Expo May 3-6 attracted salt manufacturers from Europe, India, and China and other gastronomic suppliers that use salt as an important contribution to the character of their products.

Satin's lecture on salt and health led off a series of presentations on various aspects of salt. Mort provided a comprehensive review of the current "myth information " linking salt to cardiovascular disease explaining how it was incorrect to isolate salt from the rest of the diet and then attribute risk factors to it, He recounted the scientific evidence that repeatedly demonstrated that it was not a risk when part of the balanced diet. His explanation that people consuming the Mediterranean Diet in southern Europe consume 15-20 % more salt than their northern European neighbors, but have half the heart disease and increased longevity because they have a better diet, including much higher levels of fruit and vegetable consumption, attracted significant post-presentation media attention, particularly media from Asia and the Middle East.

The remaining speakers focused on the positive role of salt iodization in reducing iodine deficiency diseases.

A second Salt Expo is planned in San Francisco next year.

We read, daily it seems, of the health risks of this behavior or that dietary factor. In cardiovascular health, we've been lectured for years about the crucial importance of such risk factors as dietary salt in determining society's rate of heart attacks and strokes.

But a recent and insightful post on Junkfoodscience reported May 2nd:

"A major medical paper on primary heart disease prevention admitted that cardiovascular disease risk factors have proven useless for predicting heart disease among our population and that reducing risks factors doesn't translate into reduced clinical disease or fewer premature deaths."

Prompting author Sandy Szwarc's contrarian comments was publication of new American Heart Association Guidelines for Cardiovascular Disease Prevention in Women which expand the number of "at risk" women being urged to alter their lifestyles to reduce their likelihood of a cardiovascular event. Trouble is, Szwarc explains:

"virtually all heart disease occurs in women without 'risk factors'…these risk factors themselves are problematic … relying on them to predict who will succumb to disease or premature death is insupportable.

"A study just published in the March issue of the Journal of the American Medical Association actually tested the AHA's proposals, among men and women. The METEOR Trial was a randomized, double-blind, placebo-controlled study conducted across 61 primary care centers in the U.S. and Europe. It examined 984 adults, with an average age of 57, who were all considered to have low risk factors for heart disease based on the Framingham Risk Score. Some received the statin, rosuvastatin, and the rest a placebo and after two years the progression of atherosclerosis was assessed by carotid intima-media thicknesses, measured by ultrasound. While the statin reduced LDL-cholesterol by 49% and resulted in small reductions in intima-media thickness, there was no regression of atherosclerosis or change in clinical outcomes."

She continues to explain that NHANES data show 85% of the population has low Framingham scores for risk while 2% have high scores, yet the AHA lumps them together to urge them all to worry about their risk and undertake lifestyle changes or begin taking medications.

"In other words, these risk factors aren't very good measures and we give them more credence than the evidence can support. That doesn't mean we should run screaming into the hills, thinking we're all going die and are all at risk, but that the evidence indicates that our obsession with these popular risk factors and numbers is not especially helpful, healthful or necessary for virtually all of us."

In support of her conclusion, she cites Dr. P.K. Shah, director of cardiology at Cedars-Sinai Medical Center. Shah wrote in the Los Angeles Times on February 28, 2005: "Our traditional risk factors are very weak overall predictors of future risk." She continues:

"The World Health Organization's MONICA project , which is an impressive 10-year study that measured cardiovascular disease mortality and disease incidences and risk factors among 10 million people in 21 countries, was also not included in the AHA evidence review. This study data continues to reveal no statistical connections between reductions in standard risk factors (obesity, smoking, blood pressure or cholesterol levels) and heart disease."

She quotes "the latest Cochrane review of 39 clinical trials conducted in multiple countries over the course of three decades, just updated in August 18, 2006:"

"In many countries, there is enthusiasm for "Healthy Heart Programmes" that use counseling and educational methods to encourage people to reduce their risks for developing heart disease. These risk factors include high cholesterol, excessive salt intake, high blood pressure, excess weight, a high-fat diet, smoking, diabetes, and a sedentary lifestyle. This updated review of all relevant studies found that the approach of trying to reduce more than one risk factor - multiple risk factor intervention - advocated by these Programmes do result in small reductions in blood pressure, cholesterol, salt intake, weight loss, etc. Contrary to expectations, these lifestyle changes had little or no impact on the risk of heart attack or death...

"Recent trials examining risk factor changes have cast considerable doubt on the effectiveness of these multiple risk factor interventions....The pooled effects suggest multiple risk factor intervention has no effect on mortality....

"Risk factor changes were relatively modest, were related to the amount of pharmacological treatment used, and in some cases may have been over-estimated because of regression to the mean effects, lack of intention to treat analyses, habituation to blood pressure measurement, and use of self-reports of smoking. Interventions using personal or family counselling and education with or without pharmacological treatments appear to be more effective at achieving risk factor reduction and consequent reductions in mortality in high risk hypertensive populations. [However], the evidence suggests that such interventions have limited utility in the general population."

The salt and health debate has featured these same issues (e.g. selective citation of the medical literature, defining-down the blood pressure levels defined as "at risk" and, of course, active efforts to persuade the entire population that everyone will benefit by reducing dietary salt intakes.

Let's stick with the facts. And, if we insist on paying attention to blood pressure, for example, as a CV risk, let's also make sure we look at the mortality associated with other risk factors which are modified when salt intake is curtailed: increased insulin resistance and accelerated plasma renin activity, for two, both of which are powerful indicators of adverse CV outcomes.

Massive publicity accompanied (even preceded) British Medical Journal publication on April 20 of the fifteenth observational study of health outcomes of lower salt diets. A team of experts led and funded by the National Heart, Lung and Blood Institute, all prominent in their previous advocacy of salt-restricted diets, reported on "Long terms effects of dietary sodium reduction on cardiovascular disease outcomes." The researchers used data from the Trials of Hypertension Prevention whose outcome was blood pressure, not cardiovascular risk, but they compared the groups that were on the low-sodium diets with the control group -- adjusting for "demographic information" and sodium excretion -- and concluded that low-salt diets confer a 25% benefit in reduced heart attacks. This was big news and received massive publicity -- more than the earlier 14 studies of the same question -- do lower-sodium diets reduce the risk of cardiovascular events and mortality? None of the earlier studies had found improved health outcomes in populations similar to Americans. Three found additional risks associated with low-salt diets.

The findings muddy the waters of the underlying question, but, paradoxically clarify the course of action. The record is clear -- observational studies are divided confirming the Salt Institute's long-standing conclusion that we need a controlled trial of the question to resolve whether public policy should advocate salt reduction. Moreover, by choosing the TOHP study, these anti-salt researchers embrace the very study design that the Salt Institute has advocated to the US Department of Health and Human Services. SI has suggested the TOHP model for the controlled trial.

Critics of the new study have observed that the findings depend entirely on five deaths among the 3,000-plus subjects and that the reduction in cardiovascular events failed to reach significance when revascularization (surgical intervention) procedures were excluded, and the change in total mortality failed to reach significance also. These are serious criticisms, but no observational study can hope to resolve these matters. Let's not get bogged down on the methods or conclusions of this single study.

The significance of this study is not its authors' conclusion that lower-salt diets will reduce cardviovascular events, but, rather, that it represents a powerful argument for a controlled trial of the question. We cannot make policy on observational studies nor on the latest single study. While the first 14 "health outcomes" studies offers no support for salt reduction in a US-type population, this study virtually demands that the question be resolved to prevent the public being confused by "dueling studies."