Salt & Human Health

British scientists at King’s College, London appear to have found a new way to regulate hypertension which involves oxidation. Oxidation in the past has generally been regarded as harmful rather than good, but researchers now acknowledge that it is central to normal cell function.

Important for all tissues, the enzyme protein kinase G or PKG is particularly functional in the cardiovascular system where it plays a fundamental role along with nitric oxide in blood pressure regulation. What the researchers discovered was a way in which PKG can be regulated independently of nitric oxide which may open up new approaches to manage hypertension. Metabolic oxidants such as hydrogen peroxide can elicit bonding between two amino acids which activates PKG, which in turn, leads to lowering of blood pressure.

The research is published in the journal Science.

Active oxidant/anti-oxidant species are generated during normal metabolism. Fruits and vegetables have been shown to contain high levels of these compounds, which provide protection against harmful free radicals and have been suggested to lower the incidence and mortality rates of cancer and heart disease in addition to a number of other health benefits. Fruits and vegetables have repeatedly shown to be extraordinarily effective in reducing hypertension and have been considered critical in reducing the burden of cardiovascular disease.

Perhaps the latest research will clarify why.

Posted by Mort Satin at 02:25 PM | Permalink

This week, Local Authorities Coordinators of Regulatory Services (LACORS), a UK government body set up to provide advice and guidance to support local regulatory services, issued a report accusing British food manufacturers of "hoodwinking" consumers by manipulating serving sizes to minimize the amount of salt.

Are you kidding? Apparently LACORS feels the food industry is as obsessed with salt as it obviously is. Salt as the only nutrient of interest? What about the food industry's desire to showcase "good" nutrients? If a single chicken nugget is a smallish "serving" then the amount of protein is proportionately small. If serving sizes are wrong, don't blame salt; get regulators and FSA together and agree on proper standards. Don't obsess on salt.

Myopia reigns at LACORS.

LACORS ignored its basic mission: to promote sound health. It has embraced the Food Standards Agency's politically-correct salt-bashing campaign, ignoring entirely that campaign's flawed assumptions and utter lack of a health outcome metric. "Success" is salt reduction, argues FSA, simply assuming a health benefit. Studies in the US and Finland have put the lie to this easy assumption.

Contrast that to the Food Dudes program whose goal it is to increase fruit and vegetable consumption in the UK. They may have a miniscule budget and certainly lack the glitz and horsepower of the FSA, but Food Dudes understands the science: increasing intakes of fruit and vegetables will not only reduce cardiovascular diseases, but a great many other chronic diseases as well. It is a pity that they don’t have the spotlight

LACORS is right on one point: the consumer IS being hoodwinked. But FSA and LACORS are doing the hoodwinking, not the food industry.

Posted by Dick Hanneman at 03:55 PM | Permalink

The August edition of IFT’s Food Technology, the most widely read journal in the food industry (monthly circulation of 35,000) just came out. The OpEd column, Perspectives, contains a hard-hitting look at those who pursue salt reduction instead of increased fruit and vegetable consumption as a means of controlling hypertension.

A Salty Red Herring describes how a diet high in fruit and vegetables leads to a much lower incidence of chronic disease and a decline in the majority of risk factors associated with cardiac disease and stroke. The Dietary Approaches to Stop Hypertension (DASH) diet, high in fruits, vegetables, and low-fat dairy products demonstrated that hypertension can easily be reduced, even in salt-sensitive people (Appel et al., 1997). However, with a diet high in fruits and vegetables, not only is hypertension dramatically reduced, but all other cardiovascular risk factors are reduced as well.

Despite the evidence of fruit and vegetables benefits, the article asks why do AMA, FSA, and CSPI continue to aggressively push salt reduction (partially reducing one cardiovascular risk factor in a small proportion of the population) and say so little about dramatically increasing the consumption of fruits and vegetables (reducing the impact of all risk factors for the total population)? In other words, why do they insist on chasing the salted red herring when a much more meaningful and beneficial resolution to many diet-related health problems is so obvious?

Posted by Mort Satin at 04:56 PM | Permalink

“Vitamins No Magic Bullet for Heart Health,” “Study doubts antioxidant benefits for heart risk women,” “Vitamins May Be No Match For Mother Nature,” typical headlines resulting from a just published study in the Archives of Internal Medicine. I find it odd that there is such an uproar over the finding that individual nutritional elements, such as vitamins C and E or the antioxidant beta carotene in pill form do not contribute to health in the same way as when they are consumed as integral components of fruits and vegetables.

This study highlights a number of fundamental problems we encounter in modern nutrition-based medical research. We have come to rely very heavily on epidemiological studies, regarding them as functional rather than numerical relationships. Theories, policies and interventions are churned out of the health establishment based upon the tyranny of statistics rather than a knowledge of the underlying physiological mechanisms. That’s how we end up with the swarm of “paradoxes,” the French paradox, the Italian paradox, etc. Is it the wine, or perhaps the omega 3, 6, and 9 fatty acids? Should we focus on flax or concern ourselves with nutrient flux? Most importantly, can we isolate the one magic bullet that will rationalize the statistics we observed? With that one magic bullet, it would be child’s play to promulgate a health policy and a simple intervention strategy. Unfortunately, life processes seldom revolve around single bullets.

Another primary problem is the lack of knowledge concerning the contradictions we observe between laboratory studies and clinical trials. As an example, most people believe that the majority of vitamin C is lost during processing because laboratory analysis indicates the ascorbic acid is gone. What has actually happened is that the ascorbic acid is converted into dehydroascorbic acid, which doesn’t show up on the standard laboratory analysis. However, dehydroascorbic acid has virtually the same health benefits as ascorbic acid. The laboratory analysis says the vitamin C is gone, it has ceased to be, it is no more, however, our astute bodies tell us it’s not – another example of the “in vitro, in vivo paradox.”

The same paradox is evident in the countless dietary studies carried out, sponsored by the National Institutes of Health. Many of these studies begin with the notoriously inaccurate, self-professed food survey - the 24-hour recall (“I don’t remember eating that Twinkie,” said the adiposed adolescent). Once this questionable set of data on intakes is collected, it is usually put through clever computer programs such as the Minnesota Nutrition Data System software which converts these stated intakes into nutrients, based upon the ubiquitous, but inadequate USDA tables and other data on proprietary food preparations. The USDA tables disregard the issue of digestibility (or more correctly, indigestibility). These tables and the numerous computerized nutrient data programs that derive from them, assume that everything is fully digested – 100% bioavailability. This is, of course, wrong. The most digestible protein, egg albumin is only about 95% digestible, while celery can be down to 65-70% on a dry matter basis. This means that a significant portion of micronutrients may not be available.

We brush aside the impact of indigestibility of individual foods as well as the impacts of one food upon another. This is strange since we have long accepted the positive, synergistic effects of foods taken together, such as bread and milk, where the essential amino acids complement one another. Why deny the flip side of indigestibility? If you eat your eggs together with a few florets of broccoli, how much of the egg nutrients do you actually digest? Without knowing with precision which nutrients are absorbed in what amounts, data is churned out, often to several decimal places, for us to ruminate and develop theories upon. Garbage in, garbage out. On top of that, a lack of appreciation of the impact of micronutrients generated by gut microorganisms confounds our conclusions even further. So we end up observing what was taken in and observing the final outcome, but not knowing much about what actually happened in the process. Not a very sound basis upon which to promulgate health policies and interventions. It highlights the disconnect between what is observed in the laboratory (i.e. the USDA tables) and what actually happens in real life.

This unfortunate combination of poorly executed analysis, imprecise knowledge of physiological mechanisms and the unremitting drive to find a singular explanation to statistical relationships results in policies, advice and interventions that do not stand the test of time. We have seen this with hormone replacement therapy, salt reduction programs and we see it again with prescribed vitamin regimes. No wonder we see headlines such as, “Vitamins May Be No Match For Mother Nature.”

Posted by Mort Satin at 11:41 AM | Permalink

Will reducing population salt intakes save the thousands of lives promised by public health agencies in the U.S. and the U.K.? The only country to achieve a significant reduction in salt intake is Finland and researchers Karppanen and Mervaala published the outcomes in the journal, Progress in Cardiovascular Diseases. Not only did they claim that the significant reduction in salt consumption led to a dramatic decrease in cardiovascular disease, but they went further and attributed the 4.5 year increase in longevity to it as well.

Since this was the first medical study to actually look at a broad-based national salt reduction with health outcomes over a 30 year period, I thought it would be worth comparing with other countries.

This comparison appears in our latest edition of the Salt and Health Newsletter. The Global Cardiovascular Infobase, makes possible a clear comparison of patterns of ischaemic heart disease (IHD) in all countries. As it turns out Finland, the only country to significantly reduce salt consumption, experienced the weakest reduction in Ischemic heart disease over the last 30 years. In fact, Canada, a country where no salt reduction took place, started at the same point as Finland, but ended up with double the heart disease reduction. That certainly doesn't say much about the positive impact of salt reduction, quite the contrary.

To check out the situation with life expectancy, I accessed the International Data Base of the US Census Bureau . Here again Finland, the only country to severely cut its salt intake, ended up with a rather small increase in logevity compared to the other countries.

Based on this Finnish study, we can say with confidence that despite an almost 50% reduction in the consumption of salt in Finland, there are no health benefits attributable to this intervention.

Posted by Mort Satin at 03:29 PM | Permalink