Peruvian anchoveta are good food. They're unusually rich in omega-3 fatty acids, high in protein, and abundant. But for the most part, we don't eat them. They're either processed for their oil for omega-3 supplements or used to feed larger fish in fish farms in Norway and elsewhere.

Catching ever-diminishing quantities of tiny fish (which also form the base of the food pyramid) off the coast of Peru to process into pellets to ship to fish farms in Norway can't be the smartest use of resources, can it? In fact, it's not, especially if you consider that global fish consumption reached an all-time high in 2016.

It's with the story of these tiny anchovies that journalist Paul Greenberg begins his around-the-world journey to Earth's fisheries in a new PBS documentary, "The Fish on My Plate," which is available for viewing now. Along the way, we stop in Norway to check out fish farms, have dinner with fisheries experts in New York, and head to Alaska to learn more about oh-so-popular salmon. And we watch Greenberg eat. During the year the documentary follows his travels, he gives up land meat and eats only fish and seafood, all to find out what its effects will be on his health in an experiment of one. You can catch a trailer for the documentary in the video below:

The search for fishy answers

Greenberg is passionate about fish — and fishing, which he has enjoyed since he was a kid. He's written two books on the subject, "American Catch" and "Four Fish: The Future of the Last Wild Food," which makes him the ideal guide to tackle the perplexing health questions around fish, primarily: Can lots of omega-3s make us feel better and improve health benchmarks like blood pressure and triglycerides? And what is the best fish to eat, for both planetary and personal health?

To get at the answer to the second question, Greenberg dives into the farmed vs. wild debate, talking to advocates on both sides who say their fish is easier on Earth's limited resources. Greenberg himself eats both, but he gets into how the impact of each scenario depends on the type of fish — some do better and use fewer resources when farmed, and some aquaculture methods are less impactful than others. He also explores new forays into fish farming, some entirely separate from the ocean itself (so no cross-contamination can occur) are changing the calculus on the impact of that industry. Farmed shrimp, for example, have long been known to be extremely problematic — due to both pollution the near-shore waters where they are raised, and also because they so often employ slave labor. But a new venture has shrimp being raised in tanks in a New York basement.

On the other hand, really well-managed fisheries, like Alaska's, rely on a wild food that has net benefits for the environment. The salmon fisheries there can function, if treated well (that includes keeping wild lands wild and protected around rivers where fish spend part of their lives) as a food resource in perpetuity. But most fisheries in most parts of the world are, as one expert Greenberg interviewed "a mess," either lacking laws, or lacking enforcement of those laws to protect fish as an ongoing resources.

We've made the same mistakes in the Lower 48 as well. As Greenberg states in the documentary, a fisheries crisis similar to what's going on in many parts of the world today occurred in California in the 1950s. Cannery Row in Monterey is now only a tourist attraction, and no longer a viable fisheries hub because Americans kept fishing even when there weren't populations to support our appetites. Seventy years later, it still has not recovered.

A problem we can solve (if we try)

The good news is that with some exceptions, Greenberg reports, most fisheries can recover with good management and the oceans can heal themselves fairly quickly. Overfishing can be addressed with smart policy and policing.

The United States makes up the second-largest seafood market in the world, yet 90 percent of the fish we eat comes from abroad, much of it from fish farms in foreign countries. And we send about one-third of our own wild catch to markets in Europe and Asia. Why?

"... the farmed stuff is cheap and the wild stuff is expensive. Americans like a bargain, even if it's a devil's bargain,' says Greenberg.

Trying to feed so many people is the main problem, says Greenberg towards the end of the documentary. But we can make better choices. When ordering fish or at the fish counter in the supermarket, Greenberg says to ask questions. "I think first of all, the number one question is: Where did the fish come from? And does the person who is selling your fish have a good handle on that?"

But when it comes to health and value, he has some more specific advice:

"Quite often, I will buy Alaskan wild sockeye salmon. People always say, 'Oh salmon, it’s so expensive.' The place where you get into trouble with wild salmon is when you start going to the fresh fish counter, where you’ll start seeing $15, $20, $25 a pound. But in fact, outside of wild salmon season from June to August, fish you’re going to see on the counter has usually been defrosted. It makes much more sense to go to the frozen food bin and get those nice vacuumed-packed Alaska sockeye salmon that usually come in around $10 a pound. It’s boneless, it’s portioned out, and because it’s been frozen the moment the fish comes out of the water, you can bet that it’s going to have a higher quality than the fish that’s been defrosted and is laying out at the fresh seafood counter."

As far as the health outcomes for Greenberg's solo omega-3 experiment? I'd urge you to check out the documentary for the answer; it's complicated and involves more than a few factors, just like most health questions and answers.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

Paul Greenberg answers the trickiest questions about fish, our last wild food
Is responsible seafood the answer to our health and environmental crises? Author Paul Greenberg explores in a new PBS documentary, "The Fish on My Plate."