Scientists at DuPont have genetically modified a yeast to produce a long-chain omega-3 fatty acid, essential to human health and previously available in meaningful quantity only from marine sources. In other words, they can create in the lab something that, up until now, we’ve had to harvest wild fish to obtain.

I’m going to tell you more about this yeast (you’re on the edge of your seat, I know), but I’d like to first ask you a question. What’s your immediate reaction when you read about a genetically modified organism (GMO) that could improve human health? Do you think, “Outstanding! Yet another way we can live better through science.” Or do you think, “Oh, please! Another bill of goods on an untested technology from a profit-hungry corporation.” 

In other words, do you have an ideological dog in this fight?

Although I try, in Unearthed, to approach each issue with a clean slate, I can’t deny that I have a dog. My dog likes the idea that we can precision-engineer organisms to be more healthful, or easier to grow, or higher yielding, but I try to compensate by talking with really smart people who have the other kind of dog.

Do a little of that, and it’s easy to see how Americans and GMOs have gotten off on the wrong foot. Although genetically modified crops certainly have benefits (which accrue mostly to farmers), if you’re a consumer concerned about an industrialized food system that produces a whole lot of cheap meat (fed with GMOs) and highly processed foods (made with GMOs), Roundup-Ready soy is hard to love.

But a yeast that generates an essential human nutrient, a nutrient that we’ve been pillaging our oceans to get? Could everyone’s dog love that?

A couple of important issues put the yeast in context. First is the value of long-chain omega-3 fats eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In a world where so many aspects of nutrition and health are disputed, the value of EPA and DHA isn’t. According to Frank Sacks, professor of cardiac disease prevention at the Harvard School of Public Health, “There is a consensus about EPA and DHA. . . . These fatty acids have wide-ranging beneficial effects on biological mechanisms concerning cardiovascular disease, inflammation, blood clotting.” We need these fats.

Also uncontested is the fact that wild fish are a limited resource. How limited? The most optimistic view I’ve found is from Andy Sharpless, chief executive of Oceana, a nonprofit ocean conservation organization. He makes the case that GM yeast isn’t necessary because better-managed wild fisheries could produce up to 40 percent more fish than they do now. Still, according to Sharpless, that’s 700 million fish servings a day from our oceans — a third of what we’d need to feed every earthling the USDA’s recommended two servings per week. And there will be more earthlings, whereas there won’t be more oceans.

A necessary nutrient. A limited source. A growing population. If we can grow EPA and DHA in the lab without having to catch any fish at all, isn’t that a boon for mankind?

That’s the question I asked some of the environmental and advocacy organizations that have generally opposed the genetically modified foods already in our food supply, including Food and Water Watch, the Center for Food Safety and the Union of Concerned Scientists.  I wanted to hear from the other dog. 

Their concerns were primarily, although not exclusively, about safety. “We’ve read all the marketing material,” said Patty Lovera, assistant director of Food and Water Watch. “We have some agreement about the state of the forage fisheries and the need to reduce wild fish oil and fish meal,” the two components that small forage fish are processed into for supplements or animal feed, “but this is starting to feel similar to other PR for biotech crops.” She’s concerned that we hear all about the benefits but not about impact when the organism gets out in the world. And our regulatory system is “decades behind,” she points out, in being able to assess GM technologies and that impact.

Jaydee Hanson, senior policy analyst at the Center for Food Safety, expresses similar concerns. He credits DuPont with releasing data about the engineering of the yeast but says he would like to see more: on the animal testing, and on what happens to the yeast in the environment. He’s particularly concerned about GRAS (generally recognized as safe) status and the fact that companies can declare their product safe without even notifying the FDA. (DuPont convened an expert panel to determine GRAS status and filed with the FDA.) Even with those concerns, Hanson acknowledges that the yeast is “probably a relatively safe product.”

Ricardo Salvador, director of the food and environment program for the Union of Concerned Scientists, is more optimistic: “I think we have to be open-minded about this. It does seem to deal with the constraint we have in sustainable fisheries.” His concern is the ecological footprint. Assuming that the oil is equivalent, he wants to evaluate the total impact of the system, including inputs and waste streams, to see if it is sustainable in the long term.

There’s a lot here that reasonable people can agree on. Yes, we need the regulatory apparatus to evaluate food safety that includes scenarios in which novel organisms get out into the environment. Yes, when we evaluate a lab-based solution we have to take into account everything that goes into it and comes out of it. Several people I interviewed mentioned labeling, and I’m on board there, too. Consumers should know both that this product was made with genetically modified yeast and that no fish were harvested in the process.

It’s important to note that fish-free DHA and EPA can also be made with non-GM algae, which is how vegan fish oil supplements are made. If you’ve ever shopped for them, you probably have an inkling of their main drawback. When I checked online, fish-derived NatureMade DHA and EPA supplements cost 26 cents per gram (of DHA and EPA). The vegan version, made with algae, cost about six times that: $1.54 per gram. Yeast is more efficient and less expensive than algae (and is also vegetarian and contaminant-free). The yeast’s oil is still significantly more expensive than conventional fish oil, but increasing demand for oil, combined with decreasing costs that come from economies of scale, should eventually make it competitive.

We can argue about the likelihood that the yeast is safe. My dog and I think it probably is. It’s not surprising that DuPont’s Mike Saltzberg, one of the scientists behind the yeast, thinks so, too. He points out that the yeast is designed to be a low-risk proposition. It’s contained in vessels in labs, and it requires a nutrient (thiamine) that it wouldn’t find in the wider world in order to survive. The oil itself is chemically indistinguishable from the fish-derived oil, and the yeast, when it’s used for animal feed (it’s now used to feed farmed salmon), is dead.

The obvious question for any consumer deciding about this is: Do you think it’s safe? But a different question might be more revealing: Do you want it to be safe? Does the fact that it’s genetically modified make you root against it, even though it could fill an important gap between our population’s growing health needs and our planet’s limited natural resources?

I think we all need to train our dogs to understand that genetic modification is a tool, and it’s the “O,” not the “GM,” that we have to focus on. If you root for the EPA-producing yeast, you can still hate the Roundup-Ready soy.

Note: An earlier version of this story misspelled the name of DuPont scientist Mike Saltzberg.

Haspel farms oysters on Cape Cod and writes about food and science. On Twitter: @TamarHaspel. She will join Wednesday’s Free Range chat at noon: