Recently, the Department of Health and Human Services launched their first Physical Activity Guidelines for Americans . This was in direct response to the national obesity epidemic whose effects can be seen everywhere. The U.S. Centers for Disease Control have stated that adult obesity rates doubled since 1980, from 15 percent to 30 percent while childhood obesity has almost tripled during the same time period, from 6.5 percent to 16.3 percent.

While it is great that these new guidelines are here, it is fair to ask why it took so long for them to be published. The answer to that is clear. The responsibility for carrying out physical activity is almost entirely in the hands of individuals. If individuals don't make the effort to do physical exercise, then there is no one to blame but themselves. This is, of course, much more related to adults than children. For children, it is both the home and school environment that is largely responsible for the amount of exercise they do.

Because of the great degree of personal responsibility associated with physical exercise, there has been little attention paid to this issue on the part of consumer advocacy groups, whose political capital is largely the result of finding businesses and large institutions to blame for problems. With reference to the obesity epidemic, consumer advocacy groups invariably blame the food industry for producing high fat, empty calorie foods, and, to a lesser extent, they blame the government for not regulating the industry. It is a very rare occurrence when a consumer advocacy group calls on consumers to bear their share of the responsibility for managing their lifestyle and matching their food consumption with energy expenditure through physical activity.

Thus, while the Physical Activity Guidelines for Americans has just been published, the Dietary Guidelines for Americans is in the process of preparation of its sixth iteration since 1980.

It is strange that it is only since the first iteration of the Dietary Guidelines for Americans that we have experienced the obesity epidemic. This does not say much about the effectiveness of the Dietary Guidelines and the people or institutions that have developed them. Considering what has happened to our physical condition in the last quarter century, one wonders if Americans would have been better off without the Dietary Guidelines. Is it possible that this could have been corrected if the Physical Activity Guidelines were issued at the same time? Not likely.

As much as the Department of Health and Human Services (HHS) and the Department of Agriculture (USDA) assure us that the Dietary Guidelines are evidence-based, they are about the worst example of this that anyone might choose. The Dietary Guidelines are predominantly based upon opinion - the absolutely lowest level of evidence in the hierarchy of acceptable evidence. In fact, some of the evidence upon which the Guidelines are based is so subjective, there have been complaints that certain of the Guidelines should never have been issued. Unfortunately, there are certain segments of our society that have an burning desire to provide guidance, no matter how ill-advised.

If you consider both the Dietary and Physical Activity Guidelines, you will see that they don't really relate to one another. (It is interesting to note that the Physical Activity Guidelines are issued by the HHS alone, while the Dietary Guidelines are issued jointly by HHS and USDA - are there some issues at play here?) While food products carry labels that indicate the energy content (calories) of each serving, it is almost impossible for consumers to easily translate this into the amount of physical activity required to expend the energy taken. People who watch their weight and exercise regularly are an exception. They have a good idea of what extra energy will have to be burned off in order to make up for extra food consumption. If they treat themselves to a few extra chocolate chip cookies, then they put in the effort to jog for an extra half hour in order to burn the calories off.

Instead of putting calories on the food label, why don't they put the physical activity equivalent on, so that people will have an idea of what they have to do to get rid of that additional intake. That is the sort of thing that will link the Dietary and Physical Activity Guidelines together - calories by themselves simply don't convey the energy input/output message to consumers.

Getting consumers to relate their diet to physical activity and energy expenditure is not rocket science. It does, however, require a sensitivity to the needs and awareness of consumers rather than a focus on political expediency and a compulsion to give advice by a medical establishment that has still to learn what food and nutrition are all about.

Britain's Food Standards Agency (FSA) has a target to reduce average salt intakes across the population to 6g per day by 2010. It selected its targets, it says, on surveys from 2000-2001 claiming British men consume 11 g/salt/day and women, 8.1 gpd. The agency announced July 22nd the publication of a survey of Britons' urinary sodium -- the "gold standard" measure for salt intake, "which shows the UK's average daily salt consumption has fallen from 9.5g to 8.6g since 2000." FSA termed the results "an encouraging decline in salt levels," but conceded its pace would fail to achieve the 6 gpd target in 2010 so it unveiled a consultation to "make its voluntary 2010 salt reduction targets, for 85 categories of food, stricter, and set more challenging 2012 targets, for 80 categories of food."

The publication behind the news release tells a different story .

Entitled "An assessment of dietary sodium levels among adults (aged 19-64) in the UK general population in 2008, based on analysis of dietary sodium in 24 hour urine samples," the methodology explains the care taken to secure accurate samples and analysis. So, we can be pretty sure that the 2008 number is sound. The study actually didn't find 8.6 grams, but rather 8.728 grams; it is expressed as 148 mmol Na (a millimole of sodium being equal to 23 milligrams; this assumes, as they mistakenly do, that all the sodium comes from salt, which it doesn't -- no matter). So they misled on the achievement, but still, reduction from 9.5 grams salt (161 mmol Na) would be an impressive achievement. Indeed, FSA continues to boast that it "is encouraged that action to reduce the average amount of salt we are eating on a daily basis is clearly having a positive impact." This, of course is not the proper metric: salt reduction isn't an end it itself. The "positive impact" would be reduced incidence of heart attacks or better than projected cardiovascular mortality -- no matter, here.

The deception arises in the 9.5 gram (16 mmol) "starting point" which turns out to be a phone survey, not a carefully controlled collection of 24-hour urine samples with quality analysis (as was done in 2008).

Fortunately, we have another exceptionally well-done survey of a representative British population. And from a good deal more vantage point so we can see just how much improvement has been recorded. Its size is nearly comparable, 754 in the 2008 survey and 598 in the Intersalt Study published in the British Medical Journal, July 30, 1988. Intersalt sampled three British populations, carefully collected 24-hour urine samples and had them analyzed in a single laboratory. The results? One population had 149.9 mmol; one 150 mmol; and the third, 151.8 mmol. A far cry from the FSA's claimed 2000-01 starting point of 161 mmol. Instead of a 13 mmol reduction to 148 mmol, over the past 20 years Briton's have changed their salt intake virtually not at all (2 mmol, probably within the margin of error).

All evidence suggests that sodium/salt intakes are largely unchanged in most populations over the past century. The high-salt consuming Finns and Japanese claim signficant reductions, but it does lead one to wonder if the "starting points" are valid in those cases.

So, when FSA makes these bold pronouncements of their "progress" in reducing cardiovascular disease in the UK by cutting salt intake, take it with a grain of salt. Ask whether beating up food manufacturers about reducing salt in their foods is really working. Is a 1.3% reduction over twenty years (even if true) worth the effort? Even using the much-lower "real" starting point, the current pace would have Britons' achieving a 6 gpd target not in 2010, but a bit further down the road -- in 2205 if the current trend can be sustained. That is, another 197 years, not two, before reaching the target of 100 mmol (6 gpd of salt). They admit they're behind schedule, but that may just be classical British understatement, right?

Let's be honest in interpreting the data. FSA has made NO PROGRESS despite the enormous pain it has inflicted on British food manufacturers and diverting resources to supporting "Sid, the Slug" has postponed real progress in improving Britons' health. No wonder FSA prefers to make up number about salt intake than face the proper challenge of improving public health.

The UK Food Standards Agency (FSA) conducts mini surveys amongst consumers on a quarterly basis in order to monitor changes in consumer attitudes towards food related issues. The latest survey was just published and there were some interesting surprises.

Despite a costly public relations campaign demonizing salt, including many television ads, which named and shamed manufacturers for the salt content in their foods, the latest mini survey revealed that consumer concerns over salt has dropped dramatically. In fact, consumer concens with salt are at their lowest level since December 2003 - years before the FSA began its aggressive anti-salt campaigns, including "Sid the Slug " and "Your Food is Full of It ."

Bravo to the British consumer. It is a fitting tribute to the quote, "You can fool some of the people…."

Terri Coles of Reuters (Toronto) recently wrote an interesting article on the new Dietary Guidelines. Coles is one of the few writers who wisely made reference to the Yeshiva University study , written by Marantz, Bird and Alderman, from the Albert Einstein College of Medicine and published in January, 2008 in the American Journal of Preventive Medicine. The authors wrote that the members of the Dietary Guidelines Advisory Committee should use explicit standards of evidence in making their nutritional recommendations. If not, their recommendations could end up producing unintended consequences that may have a negative impact on public health.

Most importantly, the authors proposed that there should be alternative and more rigorous standard for evidentiary support, and went as far as to state that when adequate evidence is not available, the best option may be to issue no guidelines . Now, how courageous is that?

Imagine - saying that you should not make any recommendations until you have reliable data - extraordinary!

The New York Times, like the Washington Post, loves to "blow the whistle" on bad actors, be they corrupt politicians, greedy businessmen or hypocritical "public interest" groups. Yesterday's Science column by John Tierney on "'Misleading' Research From Industry ?" revisits a subject of repeated comment in our blogs. We've pointed out that every funding agency has an agenda when it ponies up to support health-related research. The solution: examine the methodology and the integrity of the analysis. Too often, industry-funded studies are dismissed for bias while government-funded studies are given a free pass (despite numerous examples of why they shouldn't).

Tierney briefly reviews the disparagement of industry-funded studies, lamented by the British Medical Journal as creating a "hierarchy of purity among authors," and reports:

Now some researchers have looked to see what kind of hierarchy actually exists. After analyzing weight-loss research conducted over four decades, they've found that the quality of data reporting in industry-sponsored research does seem to be different from that in other research: It's better.

The study, published in the International Journal of Obesity , concluded: "while continued efforts to improve reporting quality are warranted, such efforts should be directed at nonindustry-funded research at least as much as at industry-funded research."

Ironically, the article appeared concurrent to the first meeting of the new 2010 Dietary Guidelines Advisory Committee whose salt subcommittee chair has enjoyed millions of research dollars leading to reports that endorsed the official government policy of universal sodium reduction while specifically opposing release of the data in those studies for independent expert analysis. So, if the Gray Lady wants another whistle-blowing target there are surely many choices.

Before the age of science, the influence of the classical Greek philosophers was so overwhelming that their simple opinions were taken as divine edicts. Anaximander (610-647 BCE) spent a good part of his life teaching students that animals were miraculously formed out of pure moisture and Aristotle (384-322 BCE) proposed that animals spontaneously arose out of soil, plants or even other species of animals. These opinions resulted in the theory of the 'spontaneous generation' of life, which held sway until the Middle Ages and beyond. Even Van Helmont (1578-1644), the famous Belgian physician and chemist, recorded detailed recipes for the preparation of spontaneously generated mice. For 2,000 years, polemics were the only means of explaining nature, for never once in the history of the debate had anyone ever thought of actually carrying out experiments to prove or disprove the validity of their theories. Francis Bacon (1561-1626) was among the first to seriously question these dogmatic theories and insisted that only careful experimentation and precise observation would lead to the truth. He became the period's most eloquent proponent of methodical experimentation and has often been referred to as the 'Father of the Scientific Method'.

In applying the scientific method to the practice of medicine, the notion of "evidence-based" medicine developed. Although it is not a new concept, it has had a renaissance in recent years, and now everyone refers to their brand of practice as evidence-based medicine. The one institution that rigorously adheres to the strictest principles of evidence-based medicine is the Cochrane Collaboration . Unfortunately, within other organizations, the term "evidence-based" is often used rather loosely and routinely ignores the rigorous discipline upon which the practice is based. What is worse, there is a lack of understanding of what quality evidence actually is. The following is the accepted understanding of the hierarchy of evidence to be used in making evidence-based evaluations:At the very bottom of the quality of evidence pyramid are ideas and opinions. They are exactly the sort of pronouncements that Bacon railed against. Even expert opinion cannot be compared to scientifically generated evidence. Yet, the Dietary Guidelines and the Dietary Reference Intakes (DRIs) upon which the Guidelines are established are predominantly based on opinion - the lowest level of evidence. In fact, when the initial call for comments to the Dietary Guidelines Advisory Committee was announced, our input focused squarely on that issue. Quoting from "The Development of DRIs 1994-2004: Lessons Learned and New Challenges ," our comments (comment ID 000010) highlighted what a number of scientists originally involved with the development of the DRIs were now saying - that we have to get away from expert opinions and start basing our judgments and policies on much more rigorous science.

Unfortunately, that is not what we witnessed at the first meeting of the Dietary Guidelines Advisory Committee (DGAC) meeting held October 30-31, 2008.

As was the case with the 2005 Dietary Guidelines, the chairperson of the sub-committee for Fluid and Electrolytes for the 2010 Guidelines is Larry Appel. As it happens, Prof. Appel is listed as a member of WASH , an advocacy group whose singular aim is: "to achieve a reduction in dietary salt intake around the world." In their justification for salt reduction, WASH focuses almost exclusively on hypertension to the virtual exclusion of all other risk factors and biomarkers that are responsible for overall health outcomes. They systematically ignore all data (including the Cochrane review and its latest reissue - ) as well as the most recent evidence that demonstrates the net negative health outcomes from reduced salt diets . How a member of such an advocacy group could be selected to lead what is supposed to be an objective advisory group is quite astonishing.

At the opening meeting, Appel made his presentation to the Dietary Guidelines Advisory Committee selectively picking all evidence that supported his salt reduction agenda and ignoring all else that didn't. He mentioned a number of NHANES studies, but ignored the most recent one as well as all others that did not agree with his opinion.

When another DGAC member brought up the issue of the possible negative consequences of reduced iodized salt consumption, Prof. Appel repeated a statement he made at a recent FDA hearing. "There is no problem with iodine in this country. We don't have goiter anymore." This was a typical Greek philosopher's statement. As it happens, our iodine values have been dropping steadily during the past 30 years, and although they are not yet at a level that would be considered a public health emergency, they are tending that way . As a result of Appel's pronouncement, there was no further discussion of the iodine issue.

All in all, the first meeting of the DGAC was a great disappointment. It appears that we are once more headed towards a series of recommendations that will result from a process based far more upon opinion than on scientifically-derived evidence. It was like retreating to the notion of spontaneous generation. This is just not on, and we will continue to do whatever we can to ensure that this process get back on track and be the product of objective science, not subjective personal opinion.

As the Mark Twain observed: "Figures don't lie, but liars figure." You may have seen the headline recently heralding research that concluded that a third of all serious heart attacks can be attributed to the "fried and salty foods" in the "Western diet." Not so fast says Sandy Szwarc in Junk Food Science .

The analysis is classic "dredge data," Szwarc points out. The researchers excluded more than half the sample without explaining how the excluded subjects compared to those retained in the reported results. The data themselves were derived from a highly inaccurate post-heart attack dietary recall survey. And that typified a series of built-in biases that included "information bias," "selection bias," "observation bias," "recall bias and reverse causation." The analysis, too, confined to risk factors, was faulty with many key factors not controlled. She commends, as we do, a further read of the work of John P. Ioannidis, M.D., with the Institute for Clinical Research and Health Policy Studies at Tufts-New England Medical Center on "Why most published research findings are false ."

The way forward, she avers and we wholeheartedly agree, is with an evidence-based approach as pioneered by the Cochrane Collaboration. She explains how the process worked in a Cochrane Review of the role of anti-oxidants in cardiovascular disease . She doesn't mention it, but the Cochrane Review on salt and cardiovascular disease concluded there is no scientific basis for a population reduction of dietary sodium. First issued in 2003, that finding was reviewed and affirmed earlier this year.

This blog post should be required reading for every medical journal editor. Go figure.

Thirteen prominent scientists will constitute the 2010 Dietary Guidelines Advisory Committee (DGAC), just named today. All are content area experts. Their views on developing evidence-based recommendations instead of past DGACs' expert opinion summaries will be determined beginning at the first DGAC meeting next Thursday and Friday. Stay tuned.

Most discouragingly, the sole appointee with a "salt" background is Dr. Larry Appel, appointed despite an obvious conflict of interest not only as a partisan in the anti-salt lobbying fraternity, but the leader of the 2005 DGAC effort which included, for the first time ever, a numeric goal for sodium intake -- a level that further research has already found problematic.

From the USDA release, members of the 2010 DGAC consists of:

Linda V. Van Horn, PhD, RD, LD, (Chair) Professor and Interim Chair, Department of Preventative Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL. Dr. Van Horn has expertise extending across many areas of nutrition research and public health as a nutrition epidemiologist who has conducted population level research in the prevention and treatment of cardiovascular disease, obesity, and breast cancer. She is currently the principal investigator in the Women's Health Initiative Extension Study and the Dietary Intervention Study in Children.

Naomi K. Fukagawa, MD, PhD, (Vice Chair) Professor of Medicine and Associate Program Director of the Clinical Research Center, University of Vermont and Fletcher Allen Health Care, Burlington, VT. Dr. Fukagawa is a board-certified pediatrician and an expert in nutritional biochemistry and metabolism, including protein and energy metabolism; oxidants and antioxidants; and the role of diet in aging and chronic diseases, such as diabetes mellitus. She has chaired the National Institutes of Health Clinical Research Centers' Committee and is currently a member of the National Institutes of Health Integrative Physiology of Diabetes and Obesity Study Section.

Cheryl Achterberg, PhD, Dean and Professor, College of Human Sciences, Ohio State University, Columbus, OH. Dr. Achterberg's research has evaluated the impact of behavior on the dietary patterns of populations, including low-income and elderly Americans. She has served on panels for numerous groups, including the World Health Organization, the Institute of Medicine, and the United Nations as an expert in nutrition education and community interventions.

Lawrence J. Appel, MD, MPH, Professor of Medicine, Epidemiology, and International Health (Human Nutrition), Division of General Internal Medicine, and Director, ProHealth Clinical Research Unit, Johns Hopkins Medical Institutions, Baltimore, MD. Dr. Appel is a physician whose research pertains to the prevention of hypertension, cardiovascular disease, and kidney disease, typically through lifestyle modification, such as dietary intake of sodium and potassium. Dr. Appel served on the 2005 Dietary Guidelines Advisory Committee as a member of the science review subcommittee and Chair of the electrolytes subcommittee. He has also served on several committees for the Institute of Medicine, including the Dietary Reference Intake Panel for electrolytes and water, which he chaired.

Roger A. Clemens, DrPH, Associate Director, Regulatory Science, and Adjunct Professor, Pharmacology and Pharmaceutical Science, The University of Southern California, Los Angeles, CA. Dr. Clemens has extensive experience in functional foods and technology with a special emphasis on probiotics and prebiotics. He has expertise in toxicology and food safety, as well as knowledge of food processing and the food industry. He is a spokesperson for the American Society for Nutrition and the Institute of Food Technologists.

Miriam E. Nelson, PhD, Director, John Hancock Center for Physical Activity and Nutrition, Tufts University, Boston, MA. Dr. Nelson is a leading authority on physical activity and energy balance, with extensive research experience integrating the science of energy balance into behavior change programs. She recently served as Vice Chair of the first Physical Activity Guidelines for Americans Advisory Committee chartered by the Department of Health and Human Services.

Sharon M. Nickols-Richardson, PhD, RD, Associate Professor, Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA. Dr. Nickols-Richardson's expertise focuses on dietary and physical activity determinants of muscle strength and bone density, as well as dietary interventions for obesity and nutrition over the lifecycle from child nutrition to older adults. She served the Institute of Medicine as a consultant on the Dietary Reference Intakes book "The Essential Guide to Nutrient Requirements."

Thomas A. Pearson, MD, PhD, MPH, Senior Associate Dean, Clinical Research and Albert D. Kaiser Professor, Department of Community and Preventive Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY. Dr. Pearson is an epidemiologist specializing in lipid metabolism and the prevention of cardiovascular disease. He contributed significantly to the American Heart Association's guidelines for prevention of heart disease and stroke, and is as a founding member of the World Heart Forum for Cardiovascular Disease Prevention.

Rafael Pérez-Escamilla, PhD, Professor, Nutritional Sciences and Public Health, University of Connecticut, and Director, Connecticut Center of Excellence for Eliminating Health Disparities among Latinos, Storrs, CT. Dr. Perez-Escamilla is an internationally recognized scholar in the area of community nutrition for his work in food safety, obesity, diabetes, and food security, with a specialty in Latinos and low-income American populations. He is currently serving the Institute of Medicine in re-examining the pregnancy weight gain guidelines.

Xavier Pi-Sunyer, MD, MPH, Professor, Applied Physiology, Columbia University Teachers College and Chief, Division of Endocrinology, Diabetes, and Nutrition, St. Luke's-Roosevelt Hospital Center, New York, NY. Dr. Pi-Sunyer has expertise in obesity, type 2 diabetes, carbohydrate and lipid metabolism, and general medicine with over 250 research papers on these topics. He chaired a National Heart Lung and Blood Institute obesity committee and has served on the Institute of Medicine Dietary Reference Intake Panel on macronutrients. He was also a member of the 2005 Dietary Guidelines Advisory Committee where he chaired the energy balance and weight maintenance subcommittee.

Eric B. Rimm, ScD, Associate Professor of Medicine, Harvard Medical School, and Associate Professor of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA. Dr. Rimm is an epidemiologist whose research evaluates the impact of lifestyle factors, particularly diet, that relate to the risk for obesity, diabetes, heart disease, and stroke. He is internationally known for his work on moderate alcohol consumption and health and has served on the Institute of Medicine Dietary Reference Intakes Panel for macronutrients.

Joanne L. Slavin, PhD, RD, Professor, Department of Food Science and Nutrition, University of Minnesota, Minneapolis, MN. Dr. Slavin is an expert in carbohydrates and dietary fiber. Her research expertise focuses on the impact of whole grain consumption in chronic diseases, such as cancer, cardiovascular disease, and diabetes, as well as the role of dietary fiber in satiety.

Christine L. Williams, MD, MPH, Vice President and Medical Director

Healthy Directions, Inc., and former Professor, Clinical Pediatrics, and Director, Children's Cardiovascular Health Center, Columbia University, New York, NY. Dr. Williams is an expert in nutrition in cancer prevention and preventive cardiology, especially hypercholesterolemia, in children. She received the prestigious Preventive Cardiology Academic Award from the National Heart Lung and Blood Institute of the National Institutes of Health for her work in preventive cardiology for children.

On several occasions, we have reported on the current research linking reduced salt consumption with increased plasma aldosterone levels and their negative health consequences . We have done this as transparently as possible because this observed phenomenon is never considered by salt-reduction advocates. They focus uniquely on blood pressure as a cardiovascular risk factor to the exclusion of all else. It is little wonder that they are at a loss to explain why more people on low salt diets are apt to die than those on regular salt diets. In fact, the BPO (Blood Pressure Only) anti-salt advocates are likely to totally ignore the LSHD (low-salt, high death-rate) linkage.

Well, the LSHD linkage is not going away. The scientific evidence is mounting as can be seen in the most recent publication of Atherosclerosis . In an article entitled, "Dietary salt restriction increases plasma lipoprotein and inflammatory marker concentrations in hypertensive patients," author Edna Nakandakare and co-authors describe the impacts of placing people on low-salt diets .

Their research demonstrated that serum triglycerides, chylomicron-cholesterol, tumor necrosis factors, renin activity, aldosterone and insulin values all increased. They concluded that reduced salt intakes induced alterations in the plasma lipoproteins and in inflammatory markers that are common features of the metabolic syndrome. Metabolic syndrome is the combination of medical disorders that increase the risk of developing cardiovascular disease and diabetes.

It should be noted that this most recent example of the negative impact of reduced salt intakes also showed a drop in blood pressure. This was expected. The difference between this study and the countless salt-reduction advocacy papers that we have seen over the years is that this research went way beyond BPO. It looked at a great many other health outcomes. That's what overall health is - a composite of discrete health effects.

When reduced salt consumption is studied and a composite of health impacts is considered, the overall balance is negative. Yes, blood pressure may drop with reduced salt consumption, but at the same time, there is a cascade of negative health impacts that result on an overall negative health impact. The LSHD phenomenon is not an artifact - more and more research is taking place that will establish its reproducibility beyond any doubt.

It remains to be seen whether the scientists chosen to develop the new set of Dietary Guidelines will adequately consider this phenomenon in their evaluations - lives may depend on it.

Packaged and processed foods sold in the United States started carrying standardized nutrition labels in 1994 when the Nutrition Labeling and Education Act (NLEA) took effect. The major goal was to increase access to nutrition information and improve consumers' ability to make healthful food choices. Since NLEA took effect, technological change has introduced new sources of nutrition information and the consumption of food away from home has continued to increase. But have these measures been effective?

A new report examines how the consumers' use of nutrition labels have changed over the decade by looking at the trend in use of various nutrition label components and demographic groups. The U.S. experience may help policymakers in other countries who are considering mandatory nutrition labeling to achieve public health goals.

The study reveals that in the decade from 1996 to 2006, consumer use of nutrition labels declined. It declined 3% for the Nutrition Facts panel, 11% for the ingredient list, and 10% for the panel's information about calories, fat, cholesterol, and sodium. In fact, only fiber and sugar did not decline over the 10-year period. Sugar held steady while fiber increased by 2% - a telling result.

The decrease in use of the nutrition label was greatest for individuals in the 20-29 year-old bracket.

If you are wondering how the government possibly misunderstood the information desires of consumers, you need look no further that the new UK Food Standards Agency (FSA) report "Consumer Priorities for Sustainable Development "

Not satisfied with spontaneous answers to questions about what is important to consumers when buying food, the FSA researchers prompted them with specific responses. They then combined both the spontaneous and prompted answer for the final result. For example, only 7% of UK consumers were concerned with salt, but after prompting, an additional 27% said they were concerned. This resulted in a grand total of 34%. Talk about fudging!

Is it any wonder we always fail to recognize the consumers' genuine desires?

The New England Journal of Medicine recently published a long-term follow-up study to determine the impact of tight control over blood pressure among patients with Type II Diabetes. Researchers at the United Kingdom Prospective Diabetes Study (UKPDS) wanted to see whether the risk reductions achieved during periods of tight control over blood pressure would be sustainable after those controls were relaxed.

Out of 5000 patients with newly diagnosed type II diabetes, they randomly assigned more than 1000 that had hypertension to either tight or more relaxed blood-pressure control regimes. Patients with blood pressures greater than or equal to 160/90 mm Hg were randomly allocated to tight-control, aiming for less than 150/85 mm Hg with either an angiotensin-converting enzyme inhibitor or a Beta-blocker or to less-tight-control aiming for less than 200/105 mm Hg. Patients who underwent post-trial monitoring were asked to attend annual UKPDS clinics for the first 5 years, but no attempt was made to maintain their previously assigned therapies.

What was the result? After the trial, blood-pressure levels fell in the less-tight-control group and rose in the tight-control group, with no significant differences between the groups after 2 years. In line with this equalization of blood pressures, there were no significant risk reductions observed between the groups 10 years after the trial.

Differences in blood pressure between the two groups during the trial disappeared within 2 years after termination of the trial. Significant relative risk reductions found during the trial for any diabetes-related end point, diabetes-related death, microvascular disease, and stroke in the group receiving tight, as compared with less tight, blood-pressure control were not sustained during the post-trial follow-up.

For more than a quarter of a century, the Department of Health and Human Services and the Department of Agriculture have jointly published a new version of the "Dietary Guidelines for Americans" every five years. In 2010, the sixth edition of this publication will come out.

With reference to the consumption of salt, the Dietary Guidelines has served the public poorly. The fact of the matter is that the figures are based entirely upon expert opinion, not scientific trials. This was confirmed in the paper delivered at the Institute of Medicine workshop "The Development of DRIs 1994-2004: Lessons Learned and New Challenges" held in Washington September 18-20, 2007 by Dr. Peter Greenwald, Director of Cancer Prevention at the National Cancer Institute of the National Institutes of Health . Dr Greenwald described how most of the figures behind the recommended dietary intakes were based upon expert opinion - the lowest quality of medical evidence - rather than randomized controlled double blind clinical trials - the highest level of evidence.

The next iteration of the Dietary Guidelines will be the sixth in the series. Are we destined to continue basing our dietary recommendations on the lowest level of evidence? What would happen if Americans actually adhered to the dietary guidelines? The only evidence we have thus far is not particularly reassuring. In two studies on healthy young adults, carried out in very different geographic locations, college students were limited to 2300 mg Na/day - the Upper Limit for sodium recommended by the Institute of Medicine (1), (2). In both cases, all the students taking part in the trial experienced elevated aldosterone levels, and in the case of the Shapiro et al. study, they all showed evidence of arterial stiffness.

These are the only experimental results we have relating to the Institute of Medicine recommendations for sodium intake. Surely, it behooves us to test whether the IOM's recommendations are safe for Americans or not. If they once more appeared in the Dietary Guidelines, based solely on expert opinion, consumers would be justifiably bound to abandon confidence in the science behind these recommendations.

It is time to step up to the plate and have the Institute of Medicine recommendations tested experimentally

We need to establish a trial with a significant group of healthy young adults who are comprehensively counseled on how to limit their sodium intake to 2300 mg/day. As a lead-in to the trial, their baseline blood pressures, 24-hr urinary sodium, and plasma renin and aldosterone levels would be accurately determined. Once the trial began and the young adults maintained their sodium intakes at 2300 mg/day, these parameters will be checked on a weekly basis. The trial will continue for 30 days and a final analyses of blood pressures, urinary sodium, renin and aldosterone would be taken.

Such a trial would give us an excellent understanding of the impact of maintaining a consumption level of 2300 mg/day of sodium or less - on blood pressure as well as renin/aldosterone levels. It would be the first large-scale trial into the effect of adhering to the IOM recommendation for sodium and will be critically important in establishing the next edition of the Dietary Guidelines. Such a trial would not be overly costly and would, for once, remove considerable doubt regarding the validity of the IOM recommendations.

(1) Kodama N, Nishimuta M, Suzuki K., "Negative balance of calcium and magnesium under relatively low sodium intake in humans," J Nutr Sci Vitaminol (Tokyo), 2003, Jun;49(3):201-9.

(2) Shapiro, Y., Boaz, M., Matas, Z., Fux, A., & M. Shargorodsky, "The association between the renin-angiotensin-aldosterone system and arterial stiffness in young healthy subjects," Clinical Endocrinolog,. 2008 Apr;68(4):510-2.

Score one for the good guys! The European Food Safety Authority (EFSA) recently adopted the rationale proffered by EuSalt and announced it would forego multi-national dietary guidelines. EFSA announced :

The main conclusion of the Panel is that it is not feasible to establish detailed and effective FBDG [note: Food Based Dietary Guidelines] which could be used at the EU level as diet-related public health priorities may differ between countries. FBDG must also take into account wide disparities in dietary habits, due to cultural differences in eating patterns and the varying availability of food products across Europe. Therefore the NDA Panel decided to focus its opinion on the scientific process underlying the development of FBDG.

EuSalt hailed the decision as "evidence for its long-standing position, namely that it is not feasible to generalise, neither globally nor on European level, requirements on the intake of salt." EuSalt argued broad guidelines would "be dangerous for many." EuSalt also expressed pleasure at the newly-announced review of the scientific process underlying dietary advisories.

The Salt Institute congratulates both EFSA and EuSalt for their enlightened advocacy.

Arguing hyperbolically that it is "even more important to reduce consumption of sodium" than to eliminate trans-fat in foods, two staffers at the New York City Department of Health and Mental Hygiene editorialized in this week's Journal of the American Medical Association (JAMA , subscription required) that "it is nearly impossible for consumers to greatly reduce their own salt intake." They urge drastic government controls to "protect the public from unhealthy food" such as restrictions on marketing foods they don't like and subsidizing the consumption of government-favored foods, zoning restrictions to bar location of restraurants that serve foods they don't like or taxes on such "bad foods."

In short, the solution is to restrict consumer choices to their know-it-all choices. "The modern food supply is tainted -- it is too salty, too sugary, and too rich in calories, and there is simply too much of such food easily available," they continue, arguing that governments should regulate the amount of salt and added sugar in foods. "Food safety for the 21st century should be reframed....public health systems must reduce the contribution of food to the epidemics of obesity and chronic disease."

Over the past year, with evidence turing against arguments for universal sodium reduction, advocates of cutting salt are becoming shriller and more totalitarian. Perhaps the the NYC Department of Health is upset that reason Magazine ranked New York City the nation's second-worst "nanny-state city" (behind San Francisco) when it comes to dietary fascism and the Big Apple is out to regain its #1 ranking.

A new analysis released today by the U.S. Department of Agriculture reported fewer Americans using federally-mandated nutrition information, especially sodium. The 2005-2006 NHANES study of 9,416 representative consumers found about 7 in 10 use the Nutrition Facts label, about the same as a decade ago. For sodium, only 66% consulted the label in 1995-1996 and that number declined 10% to 60% in 2005-2006. Among nutrients, only cholesterol fell more, 11%. Among all the listed nutrients, fiber was the only one where consumers registered increased concern as reflected in label use.

The label was mandated in 1994; sodium labeling had been in effect a decade before that.

Over the past ten years, 5% more reported "never" using the label. For salt/sodium, the increase in "never use" increased by 10 points from 12% to 22%. A decade earlier, 36% "always/often" used the sodium label; that eroded to 34%.

It would take another study to tell us why consumers are shunning nutrition information, but the pattern is consistent. Eleven percent fewer are using label health claims (37% "never") and even the ingredient list (32% "never"). With the multiplicity of advisories and the fact that scientists dispute the health consequences of cholesterol and sodium (and other nutrients), consumers are overwhelmed and doubtful about the advice they're being given. That's why the new Dietary Guidelines should adopt an "evidence-based medicine" approach in lieu of the expert panel approach of past reviews.