|A GPS for Better Nutrition? Looking Under the Hood at Hy-Vee’s NuVal System - Page 3|
|News/Features - Health|
|Written by Jeff Ignatius|
|Thursday, 21 July 2011 05:51|
Page 3 of 3
What NuVal Can’t Do
While NuVal is a godsend to many of us, it’s important to understand what it can’t do. Much of this is obvious, but the intentionally simple presentation of NuVal might make us lazy – we could use it instead of common sense.
For one thing, NuVal doesn’t address portion sizes and Americans’ tendency to overeat. Macon suggested that consumers use the U.S. Department of Agriculture’s Choose My Plate system (ChooseMyPlate.gov) in concert with NuVal.
And NuVal shouldn’t take the place of reading ingredient lists and nutrition panels. Comer said that consumers can (and should) consult the nutrition panel, but “NuVal’s an acknowledgment of our human foibles and human nature, in that we don’t always take the time ... to do all the research about all the products we’re buying.”
NutritionOverEasy.com found two related problems with NuVal and other nutrition-rating systems: “First, they set the nutritional priorities, not you.” So if your sense of what you should and shouldn’t eat diverges from conventional wisdom on nutrition, NuVal won’t be of much use to you.
The Web site continued: “The other disadvantage is that crunching all the data into a single number obscures the various ‘pluses’ and ‘minuses.’ For example, a food that’s high in sodium but low in sugar could end up with the same rating as a food that’s just the opposite: low in sodium but high in sugar. But depending on whether I have diabetes or high blood pressure, the two choices are hardly comparable.”
In other words, NuVal can’t consider your particular health situation or dietary goals. As Macon wrote: “A customer concerned about heart health may consider NuVal when choosing a salad dressing, but still choose to look for saturated fat and sodium information on the nutrition-facts panel before making a decision. Similarly, NuVal may help a diabetic customer to narrow his search for a breakfast cereal; then he may make his choice based on the fiber content.”
And NuVal doesn’t address factors other than nutrition.
For instance, it gives no advantage to organic foods, even though that’s important to many people. NuVal explains this on its Web site: “As yet, there is no widely validated evidence that organic foods have a higher nutritional value or greater nutrient density than food not grown organically. Obviously, consumers who choose organic foods may be doing so for reasons beyond nutrition – the fact that it is grown without using certain chemical controls, for example.”
Similarly, Hy-Vee dietitian Blocklinger noted that “foods that may be processed and then enriched may score equally to a product that has the same nutrient profile but that is in its natural/original state.”
The Wall Street Journal provided another example of how NuVal’s system doesn’t account for all the factors that go into consumer choice: “Kellogg Company’s Kashi brand in a statement said it tries to provide minimally processed, organic-certified food free of artificial flavors and other additives. ‘Many of the current nutrient-profiling systems don't take these values into account, which results in an incomplete picture,’ it said.”
A personal example: I’m hesitant to buy products with artificial sweeteners for my three-year-old daughter. My bias against them is admittedly based in ignorance rather than research – I fear that some of them might have adverse long-term health effects – but it’s there nonetheless. (For the record: The National Cancer Institute says “there is no clear evidence that the artificial sweeteners available commercially in the United States are associated with cancer risk in humans.”) The problem for me is that because of the penalty NuVal assigns to sugar, artificially sweetened products inevitably score higher than their sugared (or high-fructose-corn-syrup-ed) counterparts. (This can most easily be seen in soda: Coke gets gets a 1, and Diet Coke gets a 15. And that’s an illustration, not an admission that we buy soda for our daughter.) So when it comes to special treats, do I buy ice cream (typically scoring in the teens and 20s) or Blue Bunny’s Sweet Freedom Fudge Lites (artificially sweetened and scoring a miraculous 100)? NuVal’s values are at odds with my own.
Hy-Vee dietitian Mitzel explained the fudge-bar score this way: “It made sense when I considered the ingredients – basically skim milk (which scores a 91 alone) and fiber (which drives scores up).”
And Macon expanded in an e-mail on why products with artificial sweeteners score higher: “NuVal incorporates into its complex algorithm only those nutrients and ingredients that have clear, current, high-quality data demonstrating their relationship – positive or negative – to human health.”
She continued: “At this time, our extensive body of research on the safety of non-nutritive sweeteners demonstrates that they are safe and effective tools for weight-management. Excessive added sugar intake, on the other hand, contributes to a variety of health problems. In this example, the presence of non-nutritive sweeteners does not raise the score (non-nutritive sweeteners are neutral); the lack of added sugar prevents the score from dropping.”
Katz and I discussed artificial sweeteners, and he gave insight into some of the challenges of developing the algorithm. While he doesn’t like artificial sweeteners for taste reasons, he also said he has “a concern about them for which the science isn’t fully developed. It’s kind of an unanswered question in the world of science.” (He mentioned how artificial sweeteners increase one’s craving for sweetness.)
But, he said, ONQI and NuVal aren’t reflections of his own beliefs. “Although I’m the chief engineer and the principal inventor, this level of sophistication took ... a village of experts,” he said. “We really had to work by consensus.” Some people involved in the development of ONQI thought artificial sweeteners helped people reduce calories and sugar in their diets, while others though the downside was greater than the upside. As a result, he said, “what we wound up doing is splitting the difference.”
Katz said an adjustment to the algorithm “puts back” the calories that would have been present with sugar – a change that reduces the product’s considered nutrient density. Products with artificial sweeteners, however, still score higher than sugared counterparts because of their energy density, and because they don’t incur a penalty for added sugar. So the difference between their scores is smaller because of the algorithm adjustment. “NuVal essentially neutralizes that advantage,” Katz said.
He added that ONQI’s handling of artificial sweeteners might be adjusted in the next incarnation of the algorithm – which is currently in development.
ONQI 2.0, Katz said, will take into consideration new food ingredients (such as the sweetener Stevia) and new federal dietary guidelines – such as an increased recommendation for Vitamin D and recognition that different types of saturated fat have different health impacts. “We don’t ever want to be at odds in any way with federal guidance,” he said. “It’s based on and perfectly consistent with dietary guidelines ... .”
But don’t expect radical scoring changes. “The original engineering was pretty damned good,” Katz said. “More will stay the same than change.”
Still, it’s worth emphasizing that NuVal isn’t the be-all and end-all; it will evolve and be refined just like nutrition science and dietary guidelines. And as Katz readily admitted about artificial sweeteners, the science isn’t always an exact science.
Does NuVal “Work”?
Shoppers might use NuVal to make buying decisions, and anecdotal evidence certainly suggests that they like it. NuVal, for me, almost makes shopping a game between my family and the manufacturers, to see if I can outsmart their marketing; I genuinely feel empowered by it.
That’s great for shoppers’ confidence, but if NuVal truly “works,” three different but interrelated things should happen.
First, consumer buying patterns should change, and people should be buying healthier foods – both within and across categories. So customers would choose higher-scoring bread, but they’d also be buying more fresh fruit and fewer cookies.
Second, consumer health should improve. NuVal is premised on the idea that a single score is a valid basis on which one can make healthier food choices. Ultimately, Katz said, the test of NuVal is straightforward: “Do these scores actually predict health outcomes when you study large populations?” If health doesn’t improve among people who use NuVal, then the system is built on false assumptions – or people aren’t using it correctly.
Third, manufacturers should make their foods healthier. If people buy based at least in part on NuVal scores, the food industry has an incentive to improve its products nutritionally in the interest of maintaining or increasing sales.
While it’s probably too early to say with certainty that all three of those things are happening, there’s some evidence for each.
Consumer habits. Katz said stores that use NuVal are seeing changes in buying patterns. While NuVal hasn’t published these findings yet, company spokesperson Robert Keane shared sales data from two grocery chains and three categories of food: cold cereal, fresh bread and rolls, and yogurt.
In one retailer from 2008 to 2009, “scores ranked 50 or greater outperformed products with NuVal Scores from 1 to 49. Those products with better overall nutrition grew more than lower-scoring products or all products (which includes products not yet rated). In cold cereal, products ranked 1-49 saw decreases in sales volume.”
At the same retailer, “sales of cereals scoring 50 to 100 grew 5.2 percent, [while] the ROM [rest of market] volume sales change was negative 13.0 percent. These data show that the retailer with NuVal scores published on their shelf tags had stronger growth of more nutritious products.”
Results from the second retailer – which compared pre-NuVal sales to post-NuVal sales – demonstrated a similar advantage for higher-scoring products.
“People are trading up their choices within categories,” Katz summarized, but he hasn’t yet seen data showing shifts from less-healthy categories to more-healthy ones. “That would be one of the next things we’d like to see.”
Comer said Hy-Vee hasn’t tracked sales by NuVal score to see if consumer behavior is changing. “We have not in a scientific way. [But] we have anecdotal evidence of that from dietitians ... . There’s still a lot of opportunity for us there in the future to do more statistically valid or scientifically based surveys.”
All the Hy-Vee dietitians contacted for this article said they have heard stories from customers about how they’ve changed what they buy.
Consumer health. A study in the May issue of the American Journal of Preventive Medicine concluded: “Consumption of foods that lead to a higher score for the ONQI scoring system is associated with modestly lower risk of chronic disease and all-cause mortality.”
It’s only one study, but it appears to confirm the basic scientific validity of ONQI and NuVal.
Yet it doesn’t prove that NuVal shoppers are healthier. To do that, you’d need evidence that the overall diets of shoppers improve when they use NuVal, as well as evidence that they’re actually healthier.
Healthier products. This is primarily anecdotal, but Katz said he’s seeing food manufacturers change their products in response to NuVal. “It’s forcing manufacturers to compete in a fishbowl,” he said.
Citing the example of reduced-fat peanut butter, he said: “Either that product’s going to go away, or manufacturers will have to make fat-reduced [peanut] butter that doesn’t have significant additions of sugar and salt.
“And we’re starting to see innumerable examples of reformulation to improve nutrition. And that requires nothing whatsoever of the consumer; NuVal [just] needs to be there, and consumers need to be interested in nutrition ... .”
This, he said, is a triumph of nutrition over marketing.
Director, Yale University Prevention Research Center at Griffin Hospital
written by Dr. David L. Katz, July 21, 2011
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