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David Katz, M.D.

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Nutrition Guidance: Facts About Opinions About Facts

Posted: 05/22/2012 6:00 pm

An opinion about a fact is just an opinion. And that's a fact.

It's a fact of particular importance to the world of nutrition guidance, where opinions are routinely substituted for facts, and where the expression of opinion all too often takes on a religious zeal. But it's of general relevance to any form of guidance -- including that of the navigational kind.

When you really the know the best route from here to there, you don't need GPS. But GPS can surprise you.

I was driving a route between my home and my lab for years before I got GPS. GPS recommended another route I didn't know I didn't know -- along country roads that ran by a series of reservoirs -- and it was shorter, far more scenic, and had less traffic into the bargain!

I suppose some might never have tried that alternate route, assuming that if it was important, they would have known it already. That's dangerous thinking in any field.

Some people think artificial sweeteners are poisons -- and even that their use in the food supply is part of some great conspiracy in which the FDA is complicit.

Others think that sugar is the poison. For this group, products such as diet soda are clearly preferable to their full-calorie, sugar-laden counterparts. If anything, fruit juices -- which provide a concentrated dose of fructose -- may be our true nemesis, as fructose has been singled out for its uniquely pernicious effects.

The likes of T. Colin Campbell and Caldwell Esselstyn argue that meat is poison, although I have heard them emphasize quite different reasons why. Others argue passionately in defense of our omnivorous Paleolithic origins, and consider the vegans loonies on the fringe.

Some in the latter camp clamor for a return to our Paleolithic diet. But they tend to overlook the fact that our Stone Age ancestors ate mammoth, not Big Macs; expended an estimated 4,500 kcal/day in physical exertion; and consumed roughly 100g of fiber daily. Often, we don't even bother to inform our opinions with complete stories -- but rather shop for the select factoids we like best.

Some think saturated fat is bad for us; others do not. Some say dairy promotes cancer; others extol its many virtues. Some think we need more omega-3, others put all their eggs in the "eat less omega-6" basket. Speaking of eggs...

And the U.S. government considers a slice of pizza a serving of vegetable -- despite the fact that the pasta sauce earning that designation may well be a more concentrated source of added sugar than standard-issue ice cream topping (yes, I 've done the math).

To be sure, we don't have complete facts about nutrition. But we do have many -- and we certainly have enough to reach cogent conclusions about nutrition guidance. We are not clueless about the basic care and feeding of Homo sapiens!

But getting to good guidance is a tough standard to satisfy. Those involved in selling food are clearly biased and unqualified to provide it. The government is lobbied by those who sell and grow food, and all too often generates policies that reflect the will of the special interests with the deepest pockets -- as all Michael Pollan fans and all who lament the state of our Farm Bill know.

Independent experts committed to public health, and only public health, would seem to be the way to go -- but even here, there are challenges. No one person has comprehensive expertise; and every individual, and even every field, has biases. So what is required is a "team of rivals" group of experts -- with comparable credentials, but different biases. Like the jury in 12 Angry Men, such a group creates a gauntlet through which verdicts must pass -- with bias beaten up, and removed, along the way. Only the most defensible positions prevail. It may not be perfect, but it's the best anyone knows how to do -- and such teams have done things like land us on the moon.

To inform such a jury's decision-making, there must be full testimony on both sides of every issue. In the case of nutrition guidance, that means extensive review of a fairly vast literature on diets, foods, nutrients, and health effects.

This is exactly how the overall nutritional quality index (ONQI) algorithm used in the NuVal system was developed: an extensive review of relevant diet, nutrition, and epidemiology literature; decision-making by an elite, multidisciplinary team of experts not overly inclined to agree with one another; and then rigorous validation testing. It is because of this that NuVal is, to our knowledge, the only such system shown to correlate directly with health outcomes. We know about other systems that have been put to this test -- and failed it.

Some of the leading nutrition and public health experts in North America came together to help develop the ONQI. They had no financial stake in it. In fact, Griffin Hospital supported development of the algorithm with plans to turn it over to the FDA. When it was completed, we offered to do just that.

But the harsh reality is that a government effectively lobbied to call pizza a vegetable is not truly able to speak the blunt truth about nutritional quality. And so, a scientist at the FDA told me candidly he thought the bureaucracy of his agency would tie such a system up in red tape for years. He suggested that Griffin Hospital should seek a business partner to get the ONQI into the hands of consumers, and that is how NuVal was created.

One of the important implications of these origins is that while NuVal, LLC -- a for-profit business -- is authorized to license use of the NuVal system, it does not own the algorithm and has no control over it. The algorithm is, now and forever, owned by a not-for-profit community hospital that is the global headquarters of an organization devoted solely to patient empowerment in all aspects of health care. The algorithm is overseen by a team of scientists retained as advisors to Griffin Hospital, with no financial stake in NuVal. The system is of, by, and for public health -- and is walled off from any other motive in perpetuity.

These are facts. The paper trail in support of them is readily available.

But facts don't preclude opinions about facts. The peril lies in conflating the two!

Recently, a food blogger "graded" several nutrition profiling systems, including NuVal. NuVal was given a poor grade because scores were at odds with the blogger's preconceived notions. But that would be like me trashing my GPS because it recommended a route other than the one I had chosen in advance.

The blogger in question was, apparently, appalled that NuVal gave a score of 1 to "pomegranate juice," and a higher score to some salty snack food. At first, that sounds like a justifiable reaction.

Except... This pomegranate juice was NOT pomegranate juice (which, by the way, scores a 38; pomegranates themselves score a 91) -- but rather some kind of fruit cocktail made WITH pomegranate juice. The first ingredients were water and sugar -- followed by a dilute mix of juices. In other words, this is a glorified soft drink, with just enough pomegranate juice to allow for that to figure in the product's name. It reminds me of Strawberry Kiwi Kool-Aid Jammers -- which has very nice pictures of strawberries and kiwis on the package, and contains... neither strawberry nor kiwi!

Putting "pomegranate" in the name of sugar-water was enough to fool the blogger in question.

But it didn't fool NuVal. Far from being a basis to give NuVal a low score, this actually shows just how a good food guidance system should work. It should tell you what you didn't already know. It should point out the objective truth you might overlook. Which, by the way, includes the fact that most so-called "salty" snacks are less concentrated sources of sodium than most commercial breakfast cereals.

The same pertains to recent, and apparently ongoing, noise that an organization called the NCL is making about NuVal scores for canned fruit. This group seems to think that stripped-down peach bits in a can of syrup are the same as a peach direct from the tree. The NuVal scores, based on objective nutrition facts, accurately reveal the considerable distance between the two.

This same group goes on to say that diet soda should score a 0 (not easily achieved on a scale of 1 to 100), while invoking an IOM panel report that concluded that food should be judged solely on the basis of calories, sugar, sodium, saturated fat and trans fat. Using such a metric, diet soda is, in fact, "perfect" -- while mixed nuts, guacamole, and fruit juices would fare a whole lot worse. My opinion is that NuVal sorts this all out quite handily, giving regular soda a 1; diet soda a 15; fruit juices scores in the 30s; walnuts, almonds, and avocados scores in the 80s.

My GPS was right about the best route between my hospital and lab. NuVal is right about sugar water disguised as fruit juice, salty snacks that aren't very salty, and fruit bits swimming in syrup.

There is an intrinsic problem with measuring the quality of a system by how well it conforms to what you already believe. Such a system gets bonus points for agreeing with you -- even when you are wrong. If you're lost, and only follow the directions you already have -- you are going to stay lost.

We do not have perfect knowledge of nutrition, and what we know evolves like all science. Even now, ONQI 2.0 -- an update of the algorithm, based on the most recent science -- is in the works. Our intent is for it to correlate even more strongly with health outcomes that matter, and we will put that to the test.

But perfect is the enemy of good, and we certainly do have good knowledge of nutrition. Plenty good enough to get us out of the dark wood we've been lost in for the decades over which epidemic obesity and diabetes have developed.

Good nutrition guidance is based on the best available science, interpreted by the best scientists, for purposes of public health and without ulterior motives or outside influence. That's hard to achieve -- but it has been done.

Assessments about nutritional quality are apparently often based on what a food is called, rather than what is actually in it, and are just opinions -- and apt to be wrong. What's true about the covers of books is at least as true about the covers of foods.

If we sanction the evaluation of nutrition guidance by how well it conforms to what we already believe, then when we're wrong -- we are destined to stay wrong. When we're lost in a labyrinth of deceptively-labeled products, we are destined to stay lost.

GPS for nutrition can help get us out of this mess -- but only if we subordinate opinion to the facts at our disposal, work hard to keep up with new facts that come in, and acknowledge there may be things about the route from here to there we didn't already know.

-fin

Dr. David L. Katz; www.davidkatzmd.com
www.turnthetidefoundation.org

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08:21 AM on 05/25/2012
The science of nutrition is complex. People like quick, easy, and inaccurate answers. That's why we have an obesity epidemic. None of the quick, easy answers WORK.
10:40 AM on 05/25/2012
And that includes the nonsensical soundbites "eat less and move more" and "low fat".
I-US
Beware the monsters lurking in word swamps.
11:28 AM on 05/25/2012
Eat less and move more works for a lot of people. To date, it works for a majority of people.
12:43 PM on 05/25/2012
You are right. The biochemistry of digestion, metabolism, energy storage, and energy utilization is complex, as is the psychology of over-eating. While it's self-evident that a diet of 5000 calories a day is going to cause weight gain the question of why someone would feel compelled to consume 5000 calories a day is not self evident. Also the question of why one person can eat a standard diet of 1800 cal and do just fine and someone else still gains weight is also not self evident. Anyone who says weight loss can be reduced to a bumpersticker slogan is lying. Most likely they are selling something or promoting themselves. I especially hate it when physicians take advantage of the MD after their names to do just that. That's not medicine.
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Forever Jung
I can't go on, I'll go on.
08:13 AM on 05/25/2012
Eat less and exercise.
11:55 AM on 05/24/2012
Here's an idea.

A lot of people have differing diets and the most popular ones (vegan, low-carb, paleo, WeightWatchers) have simple rules which people find easy to follow.

Compare those to this rambling monstrosity of an article which goes off in all directions before getting to the point- which I guess, is to trash the critics of the system you helped develop and currently profit from, and help pump it up while never actually revealing your connections with them.
I-US
Beware the monsters lurking in word swamps.
11:06 AM on 05/24/2012
"Good nutrition guidance is based on the best available science, interpreted by the best scientists, for purposes of public health and without ulterior motives or outside influence."

--This is one of the most important lines in the article. Fad diets that are touted by people with big egos looking to profit off of well-meaning but often less-knowing individuals are dangerous. Those who tout those diets often do so with pseudoscientific claims mashed together on a personal blog. Essentially, these gurus have found a way to create bizarro nutritional science in direct contradiction to "the best available science."
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DrP
09:38 PM on 05/25/2012
It does not appear that the nutrition guidelines represented by NuVal included the best available science, such as the randomized controlled study recently published by Swedish researchers or any of the myriad of laboratory studies performed by Drs. Westman, Phinney, and Volek.
I-US
Beware the monsters lurking in word swamps.
04:11 PM on 05/27/2012
You have found an exceedingly small group of doctors that support your low-carb lifestyle and cater to your confirmation bias.
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Debby Carroll
Blogger, The Joy of Fitness, Fitness Coach
11:02 AM on 05/24/2012
Shoppers have the information they need. It's on the nutrition label if they take the time to look which most don't. NuVal sounds promising but not widely available. Why not an app? Why depend on the retailer? Meanwhile, I suggest people take time to develop a basic list of things they like that are reasonably good choices. (I say reasonably because eating all vegetables and fruits and whole grains all the time will not make most people happy and if you're not happy with the lifestyle, you just won't follow it.) On a few shopping trips, take the extra time you need to "vette" some foods. Create a list and from then on, at least for a while your shopping trips can be faster and provide you with healthy choices. You know the produce aisle is fine, so just take a bit of time in the rest of the store and create your master list of "likes." Wellness is a practice and a lifestyle, but it has to be practical and pretty easy to be truly useful.
thejoyoffitness.wordpress.com
09:12 PM on 05/23/2012
Interesting technology. The claimed 'science basis' is pretty weak and leads to some serious errors. The claim that the scores "correlate directly with health outcomes" but the link is to an article that relates nutrition to risk of disease. Sort of like claiming a score for 'light' based on research into darkness, although health vs disease is more complex than that simple comparison.

The scoring system appears to have some serious flaws, based on 'conventional wisdom' - as opposed to science. Scoring 'salt' and 'saturated fats' as unhealthy are subjective decisions, not well supported by science.

The tool is probably 'better than current product labels' but to be revolutionary it needs a revolutionary approach. An approach from a health paradigm would be much more accurate than the 'illness paradigm', but might not be very acceptable to the marketplace. It might also be more difficult to research and agree on ratings - because healthiness is not really studied. We study illness. If we want to measure healthiness, we need a health paradigm, not an illness paradigm. http://personalhealthfreedom.blogspot.ca/2011/01/health-paradigm.html

to your health, tracy
02:02 PM on 05/23/2012
Nice article, good points made about how there are so many different "food philosophies" - paleo, vegan, low fat, etc...but to me this speaks to the importance of MORE information on food lables, not less...and the NuVal system reduces a food's nutritional facts to just 1 number (1-100), making it harder for shoppers to search for the most relevant information for THEM. It may be a quick system helping those who don't have the time or ability to thoroughly scan a food's full nutrition facts panel, but it assumes that we all have the same nutritional needs/concerns, and this is not the case.

Also, I just read on the NuVal website that...

" ...soluble fiber gets all the credit it deserves, no more nor less, just as sodium, or added sugar, or trans fat in the same food gets just the penalty warranted..."

...indicating that they are able to somehow distinguish between ADDED SUGARS and natural sugars. But how exactly do they differentiate between ADDED SUGARS and natural sugars when this information is not even found on food labels? Sounds great, but I doubt that they are actually able to do this.
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David Katz, M.D.
Director, Yale Prevention Research Center; Editor-
07:02 AM on 05/25/2012
Yes, they are. NuVal does indeed differentiate intrinsic and added sugar. It's quite a lot of work to get all of the ingredient details for every food product, but Griffin Hospital supports a full time team of ~15 dietitians who population the NuVal database at this level of detail. The process is detailed in a reference manual accessible on-line at www.nuval.com.
07:52 PM on 05/25/2012
Thanks for the reply David! I did not see this information detailed anywhere in the manual available at http://www.nuval.com/images/upload/files/ONQIManual%20version3.pdf

I will send an email to "request the complete manual" from the website for this info. If this is the case, it is great that you able to distinguish between added and intrinsic sugars! Because current Nutrition Facts Panels are unable to make this distinction, and I did not know that there was a database with this information available.
01:38 PM on 05/23/2012
"Often, we don't even bother to inform our opinions with complete stories..."

Pretty much sums up most of our current cutural divisions.
09:52 AM on 05/23/2012
It seems deceitful to not acknowledge in the article that the author is one of the Doctors behind the creation of the NuVal system.
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Deadliftmcgee
09:50 AM on 05/23/2012
Were it not for your mischaracterizations, a fine article.

"But they tend to overlook the fact that our Stone Age ancestors ate mammoth, not Big Macs";
Not one single iteration of a paleo diet advocates eating Big Macs. Conflating SAD with Paleo is a common and dishonest tactic by veg folks. Paleo diets are low carb, Big Macs are not. Paleo diets emphasize eating whole foods, a big mac is not a whole food. Paleo diets emphasize eating organic veggies, fruits, and meats, big macs are not. Stop being a fibbing Franny.

"expended an estimated 4,500 kcal/day in physical exertion"
Most paleo diets emphasize physical activity, especially the lifting of heavy things, such as crossfit. Regardless, paleo adherents modify their caloric in take accordingly (ie they, you know, eat less than 4500 cals). Odd that so many have lost weight this way.

"and consumed roughly 100g of fiber daily."
All paleo diets stress eating veggies, especially leafy greens and fruits, which will yield plenty of fiber. A cursory glance at any paleo board or site would confirm this.

No need to fib to make your point.
09:08 AM on 05/23/2012
An opinion shared by Tim Noakes, renowned sports science professor, is that carbohydrates (especially simple carbs) contribute towards obesity & diabetes especially amongst people who are CR (carbohydrate resistant).
Furthermore with his new found low carb diet he has realized significant weight loss as well as improved energy levels & health.
Read more on Tim Noakes views on carbohydrates here:
http://www.total-health-fitness.com/blog/tim-noakes-on-carbohydrates
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dancerctry
I love Gardening and Decorating
08:42 AM on 05/23/2012
Here's my dilema, I'm hypoglacemic (meaning I have to eat every 2 - 3 hours or I get shakey). My choices are limited. The Nutritionist I used to see said I had to have an egg everyday for breakfast and anything else would be concidered "off the diet" I decided special K with sliced almonds is in the diet too for varieties sake!!! Lunch is restricted to salad but not just any salad it can't have Salami on it or that's not in the diet I have to stick to Chicken or Turkey on lettuce, that's it (luckily I can have dinner leftovers and there is enough variety to dinner even though most nights it's some form of Chicken where I can do this). The biggest issue is snacks though. Fruits and cheese or celery in unsalted cottage cheese. All that was fine for a while but why can't I also have some of that cheese on reduced fat crackers with the salt scrapped off? I need variety. The things that are uncontested healthy is a very small list for someone like me (also snack on unsalted cashues and string cheese). What are the non-obvious healthy foods? I hoped this article was going to answer that question.
08:46 PM on 05/23/2012
Your nutritionist is right about the egg. Make it organic and certified free range. You should be eating as much saturated fat as you like, because it is HEALTHY. Cut the polyunsaturated fats, they are contributing to your hyposglycaemia as polyunsaturates damage insulin receptors on your cells. The main reason you're getting hypoglycaemic is because you are INSULIN RESISTANT. I am the same, so is my husband, and lots of other people. The Special K is an insult to your body and will INDUCE the shakes in you, as will any grain food, cereal, bread, starch like pasta and potatoes. Take the sugar out of your diet and carry raw almonds in your pocket, their healthy fats can stave off hypoglycaemia if you chew just two or three every now and then, as long as you cut down on the sugar and carbs!
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dancerctry
I love Gardening and Decorating
11:48 PM on 05/23/2012
Actually, I had a 9 year long eating disorder. I developed hypoglacemia as my body's way of recovering from it. My diet is based on working with my nutritionist and works, there just isn't any variety to it.
03:22 PM on 05/25/2012
Alvarask...you you are totally correct..GRAINS...should not be part of insulin /hyperglycemic / hypoglycemic ..regime should avoid all that you have stated...notice how a cracker would be nice and special K has been decided as a choice..potatoes and high fructose fruits are not beneficial..usually the green apples..or some berries...and again correct on raw all fat Dairy..not the low fat read the labels on sugar content in low fat items in the diary area .. All we put in our mouth turns into sugar in the body....if you already have an insulin/hormonal situation you need to take control asap of anything that surges the system either way.
08:48 PM on 05/23/2012
I should add that if you are having ANY food that has a label on it that says "low fat" you are asking for trouble. Low fat diets CAUSE insulin resistance! So any dairy you have, such as milk, cheese, yoghurt etc should be full fat, and preferably raw so you get the maximum nutritional value.
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08:23 AM on 05/23/2012
Nuval has Tombstone 6 pack variety 6" deep dish pizza score of 99.
Nuval has cracker barrel sharp cheddar cheese non-sliced 99 and crackerbarrel sharp cheddar cheese sliced at 20... same ingredents same nutrition values on package, different scores.
Nuval is a joke and I can show the picture of the evidence.
08:49 PM on 05/23/2012
Please post a link. I would like to see it.
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Judy75201
Ms. "No Limit" Knicker
08:22 AM on 05/23/2012
Sounds promising.
08:15 AM on 05/23/2012
Thank you for standing up for NuVal--the food industry is finding sneaky ways to confuse people over what's healthy and what's not. NuVal IS a GPS to show us all once and for all what's really healthy...and mostly it isn't what you find on the store shelves, but at the farmer's market or at the farm directly.
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05:17 PM on 05/24/2012
What sneaky ways have you found?