Should we allow, require or otherwise regulate labeling of foods that involve GMO (genetically modified organism) technologies? Should labeling regulations be guided by the preponderance of scientific evidence or by the concerns of the most cautious and skeptical of consumers? Milk provides a 20-year lesson of how this might work.
There are no public data on how much of the nation's milk supply comes from treated cows. The high-water mark was probably about half, and today's share is more like one-fifth. Production incentives drove many farmers to try it. Some used it only selectively on particular cows.
Consumer reaction was and is much as we now see with other GMO products. Only a minority limited their milk purchases to products labeled as being from untreated cows, but the opponents of this technology were vigorous in their opposition. Concerns ranged from not understanding the technology to simply being very cautious about possible risks. Some consumers conflated injections of growth hormone with injections of antibiotics or confused growth hormones with anabolic steroids. The latter led developers to rename the new product as bovine somatotropin (r-bST) instead of growth hormone, thinking that the Latin equivalent would at least obfuscate the connection. Many moms expressed concerns about what this product would do to the development of their children and judged it not worth the risk. Other concerns had some basis in science, but insufficiently so to constitute a threat in the eyes of FDA. Regardless of the science, milk marketers saw an opportunity to differentiate a simple product that defied attempts at branding in the past.
As companies began to label their milk as "growth hormone free," the FDA stepped in and issued a labeling guidance: "From cows not treated with rbST. No significant difference has been shown between milk derived from rbST-treated and non-rbST-treated cows." Most labels also include words to the effect that this milk is from non-treated cows on the word of their suppliers, sometimes referred to as the "farmer's pledge". Unless milk is certified as organic, there is no other third-party certification or laboratory test that could verify a farmer's claim, so this caveat affords the processor some protection if it was somehow discovered that the claim was untrue.
Some companies chose to only procure milk from untreated cows and label their brand as such. Other companies offer "r-bST free" as a choice next to their other product. Over time, some retail and foodservice companies, seeing an opportunity to lure customers, began to insist on milk from untreated cows. Clever consumer advocates focused attention on the likes of McDonald's and Wal-Mart to create a top-down push on processors and then farmers. In New England and then into New York, r-bST was essentially banned by processors who couldn't find enough buyers for conventional milk to justify two different milk supply chains.
To this day, the preponderance of scientific research continues to support the FDA's original assessment, but the marketplace has largely consigned r-bST to a minor role in farm milk production. Its use has diminished because too many consumers could see no advantage to it and did not trust the science enough to feel it was without some risks. While many farmers continue to see value in using the product, it was not so hard to stop using it when their customers insisted. Even labeling that includes the caveat that there is "no significant difference" has tended to taint milk products without that label.
The milk story is not a perfect template for every GMO product, but it demonstrates the ability of the marketplace to sort out consumer demands, whether they are scientifically justified or not. It also demonstrates that voluntary labeling will occur and is effective. We already see many products with "GMO free" labels. For producers, it is also clear that even voluntary labeling can diminish use of an approved technology by simply drawing attention to it. While the "right to know" is a compelling reason for many of us, it begs the question whether society has a complementary obligation to better understand the increasingly complex technologies that science brings to us. It also calls into question the extent to which consumers trust government agencies like the FDA or the Department of Agriculture to watch out for them.
Novakovic is the E.V. Baker Professor of Agricultural Economics at Cornell University.