Salt & Human Health

Articles in the Chicago Tribune and Washington Post suggest that the World Health Organization's efforts to remain "politically correct" will be an uphill slog.

In the Sept 23 Tribune story, Julie Deardorff equates drinking increasingly-popular "nutritionally enhanced" waters which promise to deliver not only hydration but other health benefits to taking extra vitamins that "doesn't necessarily make you healthier." In fact, she says the only proven health benefit is to the profits of the beverage industry.

Whether fortified water can deliver on all those promises is still up for debate. Critics say there's no science to show enhanced water has more health benefits than less expensive tap water, while environmental organizations, religious groups and even restaurateurs argue that all bottled water -- enhanced or not -- is a wasteful and insupportable use of fossil fuels because of the costs associated with its manufacture and transportation. From a nutritional standpoint, experts maintain that it's better to get nutrients through whole foods.

She notes that

The premise behind functional water is that the public is chronically dehydrated and short on nutrients. And because it's often hard to change a person's behavior, food companies are changing the food they're eating or drinking.

And she includes fascinating quotes:

"As a nutritionist, I may not support [functional water], but as a public-health servant, I do," said Roger Clemens, the public-health specialist for the Institute of Food Technologists. "Our goal is to provide the best possible nutrition for 300 million people in the country. In this case, it may be it takes us looking at fortified water to do that."

and

"There's not a single drink out there -- from Enviga to SmartWater -- that has any proof of impact," said nutrition professor Barry Popkin, who directs the Interdisciplinary Center for Obesity at the University of North Carolina at Chapel Hill. "Just because [a nutrient] is in the product doesn't necessarily mean it will impact you or get in your body. There are all sorts of false labels promising health benefits.

The Post story, predictably, casts the issue in Inside-the-Beltway effects. Says Jane Black:

A billion-dollar battle over selling sports drinks and "enhanced" water in public schools has spilled into Congress and threatens to derail a major attempt to cut back the sale of junk food from school vending machines and snack bars.

In an attempt to limit the sale of high-calorie sodas, candy bars and other snacks in schools, Sen. Tom Harkin (D-Iowa) has introduced a bill that would have the government set new nutritional standards for the foods and drinks that schools sell to students outside cafeterias. But just what those standards should be is the issue.

Public health advocates want the standards to ban the sale of Gatorade and Powerade, which typically contain as much as two-thirds the sugar of sodas and more sodium, as well as sweetened waters such as VitaminWater and SoBe Life Water.

Sen. Harkin hopes to add his concerns into this year's Farm Bill in the form of federal standards and claims the Grocery Manufacturers (which has "historically resisted any regulation" is open to the idea. We suspect that GMA would insist on federal pre-emption; a likely deal-breaker for Harkin.

Back in Geneva, WHO may be scratching their collective heads wondering how they ever got crosswise to their normal bedfellows who are taking stronger and stronger exception to the notion that beverages be considered a significant nutrient source. So, whether the drinking water is "artesian water," "mineral water," " purified water," "sparkling bottled water," "spring water," or just plain tapwater, the view seems to be: use it for hydration, not nutrient fortification.

Which, of course, raises a whole new set of questions never addressed by the journalists: what about fluorodated water or iodized water? Both have been used instead of using salt as the carrier.

Posted by Dick Hanneman at 04:42 PM | Permalink

Anti-salt zealots display a religious fervor for their cause, trampling scientists who remind them that actual evidence of a health benefit exists only in the end product of elaborate mathematical models extrapolating only blood pressure effects (and even those are often shrouded in withheld statistics preventing replication). There's an arrogance to their advocacy. And a familiarity.

Investigative science reporter Gary Taubes published the lead story in the New York Times Magazine on September 16, asking "Do We Really Know What Makes Us Healthy?" It's the tragic story of well-intended, plausible advocacy of hormone replacement therapy (HRT) for post-menopausal women. The bright promise, the powerful claims and the glittering possibilities all came crashing down a few years ago when it was found that for many if not most of the target audience, the "cure" was killing far more than it was helping.

Taubes called for more "self-doubt" and recommital to the discipline of scientific investigation, foregoing the passion of the righteous objective for the surer cycle of scientific advance -- proposing hypotheses, testing them to discard most of them and then repeating the cycle to refine those who pass muster.

As he pointed out:

While it is easy to find authority figures in medicine and public health who will argue that today’s version of H.R.T. wisdom is assuredly the correct one, it’s equally easy to find authorities who will say that surely we don’t know. The one thing on which they will all agree is that the kind of experimental trial necessary to determine the truth would be excessively expensive and time-consuming and so will almost assuredly never happen. Meanwhile, the question of how many women may have died prematurely or suffered strokes or breast cancer because they were taking a pill that their physicians had prescribed to protect them against heart disease lingers unanswered. A reasonable estimate would be tens of thousands.

In conclusion, Taubes cautions:

All of this suggests that the best advice is to keep in mind the law of unintended consequences. The reason clinicians test drugs with randomized trials is to establish whether the hoped-for benefits are real and, if so, whether there are unforeseen side effects that may outweigh the benefits. If the implication of an epidemiologist’s study is that some drug or diet will bring us improved prosperity and health, then wonder about the unforeseen consequences. In these cases, it’s never a bad idea to remain skeptical until somebody spends the time and the money to do a randomized trial and, contrary to much of the history of the endeavor to date, fails to refute it.

Epidemiology has its limits, and Taubes explains how epidemiologists moving from infectious diseases a hald century ago to apply the same techniques to prevention of chronic disease have come a cropper:

In the case of H.R.T., as with most issues of diet, lifestyle and disease, the hypotheses begin their transformation into public-health recommendations only after they’ve received the requisite support from a field of research known as epidemiology. This science evolved over the last 250 years to make sense of epidemics — hence the name — and infectious diseases. Since the 1950s, it has been used to identify, or at least to try to identify, the causes of the common chronic diseases that befall us, particularly heart disease and cancer. In the process, the perception of what epidemiologic research can legitimately accomplish — by the public, the press and perhaps by many epidemiologists themselves — may have run far ahead of the reality. The case of hormone-replacement therapy for post-menopausal women is just one of the cautionary tales in the annals of epidemiology. It’s a particularly glaring example of the difficulties of trying to establish reliable knowledge in any scientific field with research tools that themselves may be unreliable.

Advocacy of HRT was based on epidemiology. Again, Taubes:

The dangerous game being played here, as David Sackett, a retired Oxford University epidemiologist, has observed, is in the presumption of preventive medicine. The goal of the endeavor is to tell those of us who are otherwise in fine health how to remain healthy longer. But this advice comes with the expectation that any prescription given — whether diet or drug or a change in lifestyle — will indeed prevent disease rather than be the agent of our disability or untimely death. With that presumption, how unambiguous does the evidence have to be before any advice is offered?

The catch with observational studies like the Nurses’ Health Study, no matter how well designed and how many tens of thousands of subjects they might include, is that they have a fundamental limitation. They can distinguish associations between two events — that women who take H.R.T. have less heart disease, for instance, than women who don’t. But they cannot inherently determine causation — the conclusion that one event causes the other; that H.R.T. protects against heart disease. As a result, observational studies can only provide what researchers call hypothesis-generating evidence — what a defense attorney would call circumstantial evidence.

Testing these hypotheses in any definitive way requires a randomized-controlled trial — an experiment, not an observational study — and these clinical trials typically provide the flop to the flip-flop rhythm of medical wisdom. Until August 1998, the faith that H.R.T. prevented heart disease was based primarily on observational evidence, from the Nurses’ Health Study most prominently. Since then, the conventional wisdom has been based on clinical trials — first HERS, which tested H.R.T. against a placebo in 2,700 women with heart disease, and then the Women’s Health Initiative, which tested the therapy against a placebo in 16,500 healthy women. When the Women’s Health Initiative concluded in 2002 that H.R.T. caused far more harm than good, the lesson to be learned, wrote Sackett in The Canadian Medical Association Journal, was about the “disastrous inadequacy of lesser evidence” for shaping medical and public-health policy. The contentious wisdom circa mid-2007 — that estrogen benefits women who begin taking it around the time of menopause but not women who begin substantially later — is an attempt to reconcile the discordance between the observational studies and the experimental ones. And it may be right. It may not. The only way to tell for sure would be to do yet another randomized trial, one that now focused exclusively on women given H.R.T. when they begin their menopause.

And he continued:

In January 2001, the British epidemiologists George Davey Smith and Shah Ebrahim, co-editors of The International Journal of Epidemiology, discussed this issue in an editorial titled “Epidemiology — Is It Time to Call It a Day?” They noted that those few times that a randomized trial had been financed to test a hypothesis supported by results from these large observational studies, the hypothesis either failed the test or, at the very least, the test failed to confirm the hypothesis: antioxidants like vitamins E and C and beta carotene did not prevent heart disease, nor did eating copious fiber protect against colon cancer.

It's a long article and a great read, but the point's been made: We need controlled trials to prevent other HRT tragedies. And a great place to start would be for salt where only observational studies have been done of the projected health outcomes and most of those studies show either no benefit or actual increased risk.

Posted by Dick Hanneman at 05:25 PM | Permalink

You can't discern the cankers and the warts at 30,000 feet, but taking in the big picture often helps us understand the motivations that play out as the tangled inconsistencies of daily news stories about health. There are some whose mission in life is to point in alarm at instances where individuals or society comes up short -- where problems mar perfection. These professional and persistent pessimists, in the health arena, would have us focus attention and resources on such interventions as dietary changes ostensibly to effect improved health outcomes, but based only on plausible, but unproven scientific evidence.

A blog today on JunkFoodScience hits the nail on the head:

There’s been so much good news recently about the state of our health and that of children. This has clearly distressed alarmists. To keep their gloomy myths alive, they’ve tried to: A). bury the news and B). convince us that good is really bad.

With people not buying any of that, they’ve added plan C: scream louder. As Dr Ian Campbell, medical director of Weight Concern, told the BBC news this week: “We are not making enough progress!”

Facts have such a troublesome habit of getting in the way of agendas. Let’s look at three major new health reports that all brought good news.

Author Sandy Szwarc points out that the 2006 National Health Interview Survey released recently found 88% of Americans self-report good or excellent health, new figures released this past week from the Centers for Disease Control and Prevention showing strong historic trends of lengthening life expectancies and falling rates of heart disease, and a UNCEF announcement this week that more children are surviving today than ever before in history.

We think the glass is at least half full, and filling steadily.

Posted by Dick Hanneman at 10:54 AM | Permalink

During our daily review of legislation related to salt, it was a pleasant surprise to come across the final filing and adoption of the West Virginia division of health nursing home licensure rule that became effective July 1, 2007. The purpose of this legislation was to implement state and federal law governing the licensing, operation, and standard of care in nursing homes located in the State of West Virginia. The goal is to help each nursing home resident attain or maintain the highest practicable physical, mental and psychosocial well-being.

Among the requirements explicitly stated are:

8.15.d. - A nursing home shall provide each resident with:
Food prepared with salt, unless contraindicated by a physician's order; and, the salt should be iodized.

Posted by Mort Satin at 04:47 PM | Permalink

Perhaps you read the article published this week in the online Journal of Human Hypertension (paid subscription required) by Dr. Graham MacGregor claiming dietary salt was responsible for high blood pressure in children. MacGregor and colleagues claim their results support "a reduction in salt intake for children and adolescents."

Not so fast. Though the media carried the author's conclusions from the study, an accompanying editorial (free) by Dr. Michael H. Alderman, immediate past president of the International Society of Hypertension, in the same edition points out that the entire relationship is due to the fact that those who ate more salt ate more food. Adjusting for caloric intake wiped out the significance of the relationship. Nor was there any difference between the high-salt and low-salt groups in terms of preference for adding salt at the table. Alderman pointed out that those consuming more salt and calories may also have had more adequate intakes of other vital, growth-related nutrients, but that the study did not include these data. Thus, Alderman concludes that the data "support the Cochrane Collaboration conclusion that there was not sufficient evidence for a general dietary recommendation to reduce sodium intake."

Alderman cautioned against following MacGregor's prescription of having children reduce dietary salt.

...randomized clinical trials in adults have shown that lowering sodium intake increases sympathetic nerve activity, reduces insulin sensitivity, increases the activity of the renin-angiotensin system and increases aldosterone secretion.

Do these or other changes occur in children? This is critical because, of course, the health impact of any intervention is the sum total of all its consequences. While I remain an agnostic on that score, I continue to believe firmly that solid knowledge based on evidence of benefit and risk must precede any clinical or public health intervention -- particularly when it comes to dependent children. Good observational studies such as this one generate hypotheses. They need to be tested in clinical trials. Absent such evidence, and absent some pressing public health challenge, therapeutic restraint may be the best and safest way to avoid doing harm.

Alderman may be "agnostic" with regard to his pursuit of an evidentiary basis for an intervention. It's too bad too many proponents of salt reduction seem to advance their arguments with strong faith and religious zeal -- and without scientific basis. We've heard no better argument against the establishment of a state religion.

Posted by Dick Hanneman at 01:15 PM | Permalink

The U.K. Telegraph reported the story of 110 year old Mary Brown, of Surrey, who attributes her cenetenarian plus status to sprinkling all of her food with plenty of salt. Despite all the negative publicity issued by the Food Sandards Agency's anti-salt campaign, Mary kept to her regular consumption of salt and has lived far beyond the average life expectancy. We wish her continued life and good health.

This is not the first time we hear that salt contributes to continued good health in later years. One Canadian cardiologist wrote us that he felt the low salt diets often prescribed to the elderly led to chronic dehydration and hyponatriumia (salt defficiency). As a result. people became very drowsy and suffered a range of salt-defficiency-related metabolic disorders. Often, this led to instability in walking or standing and a significant jump in the risk of large bone or pelvic fractures - all due to a low-salt diet. The cadiologist in question had been treating patients for 65 years - more than a lifetime of experience. He finishes his letter by saying,

"Spending your golden years in a retirement home with a low-salt diet will convert your last years to a long chronic illness."

Despite her love for salt, 110 year old Mary Brown says, "Everything else should be taken in moderation, except family and friends.

Posted by Mort Satin at 11:54 AM | Permalink

This past week saw the announcement of the European Food Safety Authority (EFSA) Scientific Colloquium 9 - Nutrient Profiling for foods bearing Nutrition and Health Claims, to be held from 11 – 12 October 2007 in Parma, a city best known for its fabulous Parma Ham*, as well as the King of cheeses, Parmigiano Reggiano**.

Not surprisingly, the European food agency at the forefront of the nutrient profiling is the Food Standards Agency (FSA) of the UK. Concerned with the rise in obesity, the FSA looked for approaches to nutrition that had the potential to make it easier for consumers to make healthy choices. They argued that it was really the 'imbalance' in the consumption of individual foods that caused health problems, not the overall balance of the diet. It’s really not the Mediterranean Diet, it’s the fish…or is it the olive oil….the fruits and vegetables….the capers…..truffles…?

In other words, food is considered to be little more than an independent carrier of nutrients. Depending upon the ‘balance’ of these nutrients, foods would be characterized in a nutrient profile. That not being enough, the profiles would be accompanied by decision signals such as traffic lights that would make it even easier for the consumers to make an “informed” decision. Traffic lights are considered to be useful signals for any being at or above the intelligence of a magpie.

It now appears that, in Europe, this concept has reached a point of no return. The ultimate price that Europe, formerly the global pedestal of fine food, had to pay for nutrition and health claims regulation. The rest will be tedious bureaucracy.

In her landmark book, “The March of Folly,” historian Barbara Tuchman defines the characteristics of folly as initiatives that: 1) are contrary to the self-interest of the society pursuing them; 2) are conducted over a period of time, not simply a burst of irrational behavior; 3) are conducted by a number of individuals, not just one deranged maniac and, most importantly; 4) are cautioned by a considerable number of people alive at the time who pointed out correctly why the initiative in question was folly.

In future blogs, we hope to examine the folly of nutrient profiling in detail. If foods were nothing more than carriers of nutrients the future of eating will be little more than a large, perfectly balanced food pill accompanied by a glass of water, and, if you really felt nostalgic, a glass of water and a gelcap of wine concentrate. Good food culture does exist and doesn’t require a traffic light to legitimize it. Rather than invent a new model, perhaps it would have been better to copy another neighbor’s successful model – but I guess that’s not what the sweeping powers vested in public authorities do.

We will also look at the science of nutrient profiling. Our entire base of knowledge for nutrients in foods comes from chemical analysis. To make matters worse, the nutrient profiles reflect laboratory analytical results, not the bioavailability of nutrients in living systems. The impact of one food component upon the other in the gut is never determined for the profiles. Fiber decreases digestibility and consequently bioavailability – how is this factored into the profiles? In fact the profiles never consider indigestibility - a total disgrace from a nutrition science point of view and a matter that would make Dennis Burkitt, discoverer of Burkitt’s Lymphoma and one of Britain’s most intuitive scientists of the 20th century turn over in his Bisley, Gloucestershire grave.

The nutrient profiles give no indication of the interactions and dynamics taking place in the gut when normal diets are consumed. Dietary regimes incorporate particular food combinations and we have never determined how indigestibility of one component may affect nutrient availability of all other components in the diet. Because the nutrient data tables we use don’t relate to this issue at all and, by use of these tables, we incorrectly presume that there is no such interaction – even though not single a nutritionist would agree with this. Thus, the inexorable march of folly rolls along.

*Pig meat profile #4276 (water 50,84%; protein 22,75%; salt 4,84%; fat 21,01%)
** Salt-cured cow milk curd profile #76383 (water 31.98%; protein 36.14%; salt 2.28%; fat 28.6%)

Posted by Mort Satin at 11:29 AM | Permalink