One of the disquieting trends in modern nutrition—and frankly, there are quite a few—is the contention that fortification makes any food a good food.
A time-honored example is breakfast cereal. Who hasn't heard a sonorous announcer conclude a television commercial by declaring that some kids' cereal that would otherwise seem a lot like a bowl full of jelly beans is "fortified with 11 essential vitamins and minerals—part of a complete breakfast!"
They tend not to mention that it can be a very dubious part of a complete breakfast. Nor do they tend to specify in what way it's complete.
This was bad enough, but now we have vitamins and minerals added to almost every edible thing, including soda, and even water. The food industry would have us believe this makes the food better for us. I disagree.
What is in play here is the definition of functional food, or functionally enhanced food. Our bodies need essential nutrients; that, of course, is what makes them essential. Our culture seems to have accepted the notion that adding such nutrients to foods always enhances them.
Michael Pollan argued eloquently against this notion in his January 2007 New York Times Magazine story. Nutrient fortification of everything as a basis for implying a food is nutritious is the very epitome of the dangerous trend Pollan referred to as "nutritionism"—the substitution of an unhelpful focus on isolated nutrients in place of the far more constructive focus on wholesome foods and overall nutritional quality.
For my part, I don't think a food that is dysfunctional to begin with can be made functional with the addition of vitamins and minerals. To borrow a metaphor, this is putting lipstick on a pig.
Unfortunately, there doesn't seem to be a universally accepted, or even commonly accepted, definition of a functional food. That invites the kind of mischief we are getting and needs to be fixed. I don't think the job is all that hard.
A good, operationally useful definition of a functional food is a food that is of intrinsic nutritional value, which is then enhanced with nutrient additions directed at some specific and measurable function. It stands to reason that a food cannot be "functional" if the function in question cannot be specified or measured.
So, for instance, monounsaturated oils and omega-3 polyunsaturated oils can be used to make a dressing or spread to which plant sterols are added for lipid lowering; that would qualify as a functional food. The food has intrinsic nutritional value, and the addition is directed at a discrete and measurable function. Plant sterols can lower LDL cholesterol.
The addition of probiotic bacteria to organic, fat-free, plain yogurt is another good example. The yogurt is of established nutritional value, and the probiotic is directed at what we euphemistically refer to as "regularity." That, too, is a discrete and measurable function.
Other functional foods occupy more expansive public health terrain. The addition of vitamin D to milk helped eliminate the rickets epidemic that overtook children amid the industrial revolution as they moved from sun-filled days on the farm to long days in factory shadows. The addition of folate to grains (and to satisfy my proposed definition, whole grains in particular) has helped to slash the rate of neural tube birth defects. A case can certainly be made for additions of other vitamins, minerals, fiber, omega-3 fats and perhaps other nutrients.
But only when the form of fortification follows some particular function can a food be deemed "functional." Fortification should not be used to exonerate nutrition that is missing in the food itself. Adding vitamins to soda, or sweetened water, does not redeem the product.
For one thing, there is no evidence that such nutrient additions are doing us any good. We know far more about the benefits of nutrient-dense foods in harmonious combinations than we do about nutrients in isolation. Foods rich in antioxidants, for instance, are consistently associated with beneficial health effects. Studies of isolated antioxidant nutrients have consistently disappointed.
For another, many of the nutrients being added willy-nilly to our food supply are not nutrients in which most of us are deficient. What, then, is the purported function?
Further, when nutrients are added to foods in this haphazard manner, we lose all ability to gauge our intake. The risk of vitamin and mineral overdose is generally low, but when even water has them added to it, it's certainly not zero. Studies hinting at increased cardiovascular risk with excessive intake of supplemental calcium (but not calcium native to food) provide a precautionary tale worthy of careful consideration.
And finally, nutrients native to foods are in native company. It's quite likely that some of the beneficial effects of nutrients pertain to the company they keep, just as the charms of an orchestra depend on the contribution of individual instruments to the melodious whole. In our random dispersion of nutrients across the food supply, we are much at risk of unmaking the music.
General Mills' Total cereal, famously, offers 100 percent of the Recommended Dietary Allowance (RDA) for a whole list of nutrients. But that's not because any of the ingredients in Total is an exceptional source of intrinsic nutrition. It's because a veritable multivitamin is thrown into the recipe. True, the first ingredient is whole wheat—but the second is sugar. There are more grams of sugar than of fiber, and a fair amount of added salt as well. That's quite a lot of baggage for the delivery vehicle of a multivitamin.
If you want to take a multivitamin, skip the middleman and take one. And then go ahead and have a totally wholesome breakfast. (For what it's worth, my standard fare is a mix of berries and other diced fruits, Nature's Path whole-grain cereals or oatmeal and non-fat, organic, plain Greek yogurt.)
And so it is that we have long been, at best, flaky about functionally enhancing foods. We should resist the devolution of this concept where credit card meets cash register. If a food lacks native nutrition, nutrient additions can't fix it. If nutrient additions don't perform a function that can be defined and measured, they cannot reasonably be deemed "functional."
There is no meaningful evidence that random nutrient additions to soft drinks and sugary cereals are doing us any good, or compensating for the native liabilities of such foods. The food industry might like to get away with the implied claim that enough nutrients at the end of a long ingredient list of junk confer a salutary glow. But let's not buy this unsubstantiated baloney. Doing so would be, in a word, dysfunctional.
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David L. Katz, MD, MPH, FACPM, FACP, is a specialist in internal medicine and preventive medicine, with particular expertise in nutrition, weight management, and chronic-disease prevention. He is the founding director of Yale University's Prevention Research Center, and principal inventor of the NuVal nutrition guidance system. Katz was named editor-in-chief of Childhood Obesity in 2011, and is president-elect of the American College of Lifestyle Medicine.