Journalist, ocean conservationist discuss marine ecology

Best-selling journalist and ocean conservationist Paul Greenberg discussed his recent book, “The Omega Principle: Seafood and the Quest for Long Life and a Healthier Planet” Tuesday in DeBartolo Hall. The event was sponsored by the Notre Dame minor in sustainability and the department of environmental engineering.

Greenberg began the talk by introducing himself.

“I’m not famous exactly — I’m fish famous,” he said.

Greenberg has had a long career writing about marine biology, but recently shifted his focus to dive deeper into the trending topic of omega-3s, a fatty acid that can be measured in humans’ blood.

“I got tired of talking about the overfishing thing,” Greenberg said.

He went on to discuss his growing interest in various specific species of marine life, from plankton to krill, and the interactions between creatures from the bottom of the food web to the top. However, he said he knew intrinsically that a book about tiny ocean creatures might not garner public interest. Looking deeper into the connections between the species, he found a link.

“The thing that tied them all together was this — omega-3,” he explained, pointing at a slide of the popular marine-sourced dietary supplement.

This finding led him to restructure the theme of his most recent book, taking a deep journalistic dive into omega-3s. The fatty acid has already gained attention for seemingly pseudo-scientific reasons, he said. The internet is rife with such claims about the power of omega-3s to improve human health, and recent years have seen a health craze around omega-3s, both as supplements in pill form and in dietary sources such as salmon.

“What if you put ‘Omega-3’s might’ or ‘Omega-3’s may’ into Google?” Greenberg asked.

Under suggested searches, he said what he found were varied and sometimes absurd.

“‘Omega-3’s may ward off Lou Gehrig’s disease … Omega-3s may help kids with ADHD,’” he said. “‘Omega-3 may boost sperm competitiveness.’”

Greenberg went on to discuss the recent science behind these assertions. Very soon after they started to consume shellfish, one theory goes, early humans suddenly began complex language development and reached other developmental milestones, possibly influenced by the omega-3s in the new food source. If this theory proves true, the shift towards consuming shellfish may have played a vital role in the development of our own species.

Hype around the possible benefits of omega-3s grew further when a researcher investigated the Inuit people of Greenland, who have a diet high in fatty fish and seafood, Greenberg said. They found that the local populations had high levels of omega-3 fatty acids, as well as extremely low rates of cardiovascular diseases.

“So why is this important?” Greenberg asked. “Well, it seems that there might have been some element of having omega-3s in our diet that evolutionarily affected our ways of being on the planet.”

As described in the talk, Greenberg’s book integrates not only questions about omega-3s’ potential benefits for human nutrition, but also the broad interactions between their sourcing, production and distribution, and their implications for ecosystem health.

His career has also ventured into the experimental: In 2017, Greenberg followed through on a dare and made a PBS documentary in which he consumed fish at every meal, three times a day, for an entire year.

Undertaking a blood analysis with omega-3 index report at the end of his project, he said he was told he “had the blood of a Sicilian fisherman circa 1890.”

Regarding the health benefits of omega-3s for humans, Greenberg ultimately said the results are not conclusive. His research still grapples with the question of whether all this was causation or simply correlation.

Greenberg reminded the audience that just because two factors appear simultaneously does not mean one causes the other. He shared his general conclusion that humans do need some omega-3s in their diets to promote heart health, but that the threshold matters.

In terms of human consumption, the science remains unclear.

“You do need to have some omega-3s,” Greenberg said. “But where that threshold is is a little bit squishy.”