People in China, Japan, and other Asian countries have long consumed jellyfish as a delicacy and for their supposed medicinal qualities. Sea turtles, as well as sharks, swordfish, and some other marine life, also like to eat these gelatinous sea critters, which are in the same phylum (Cnidaria) as sea anemones and corals. Even jellyfish like to eat jellyfish, sometimes preying on other species.
But whether you care to eat jellyfish yourself is a matter of taste and experience—if you’re up for it at all. Of the many jellyfish species in oceans around the world, only a few are edible by humans.
The lowdown on jellyfish
With both a crunchy and chewy (some say gristly) texture, jellyfish, also called sea jellies, are about 95 percent water and thus low in calories and rather flavorless on their own. The rest is protein (about half collagen), with negligible fat, no carbs (or fiber), and a range of nutrients, including potassium, magnesium, calcium, silicon, zinc, selenium, iron, copper, and choline.
You can find jellyfish on some Chinese restaurant menus in the U.S. You can also find them in some Asian markets, ready-to-use or dried (preserved in salt, similar to dried cod). The bell (dome part) and oral arms (the structures around the mouth that hold the stinging cells), but not the tentacles, are eaten. Needless to say, unless you’re an expert, you should never attempt to collect any jellyfish you may spot in the ocean or on a beach, since they may be poisonous and dangerous to even touch.
Dried jellyfish are typically prepared by soaking them in water (which removes some of the excess salt), then blanched and sliced. A handful of recipes for jellyfish “salad” on the Internet call for marinating the slices in mixtures of soy sauce, vinegar, sesame oil, chili oil, garlic, scallions, and sugar and chilling before serving. One recipe describes how to make a jellyfish burger. Jellyfish can also be added to stir-fries, noodle dishes, and leafy green salads.
Scientists are now working on a method that will produce dried jellyfish that can be eaten like chips (as shown in this video), with a texture that may be more pleasing to people in the Western world. There is also jellyfish ice cream from a Japanese company. It’s made by soaking cubes of giant Nomura jellyfish in milk and has a slightly chewy texture. It’s not available in the U.S., however (and may never be).
From traditional to new uses
Jellyfish are consumed as a traditional remedy for such ailments as joint pain, high blood pressure, fatigue, and digestive problems. In preliminary lab studies, jellyfish have shown antioxidant, anti-hypertensive, cholesterol-lowering, immune-stimulating, and other potential therapeutic properties, attributed possibly to their collagen and bioactive compounds. The collagen has also been shown to have anti-arthritic effects in mice. But such potential benefits have not been tested, let alone proven, in people.
Nor are there convincing data to support claims that jellyfish are a “brain-healing food” that can improve memory and cognition, despite the promises made by the dietary supplement Prevagen, which contains the protein apoaequorin, originally derived from jellyfish. There’s no evidence that this protein is absorbed intact, and even if it is, that it can cross the blood-brain barrier and have effects in the brain.
Jellyfish collagen is also being used as an “anti-aging” ingredient in some pricey skin-care products—the idea being that since jellyfish are capable of regeneration (one “immortal” species even reverts to earlier life stages), then applying it topically will make skin young again. Jellyfish are genetically structured for these types of regeneration, but there is no basis for believing that a similar process will take place in people who are exposed to jellyfish collagen.
Still, jellyfish hold promise in the development of future medicines. Research is active. Developing pharmaceutical uses, along with more food uses, for jellyfish is also a good way to address the problematic blooms of jellyfish that occur regularly in oceans—and increasingly as oceans warm due to climate change. These swarms further threaten overfished fish stocks, since jellyfish feed on fish eggs and fish larvae. If you can’t beat ’em, eat ’em.
Eco-note: Sea turtles may mistake plastic bags floating in the ocean for jellyfish, and if they ingest them, they can become ill. Another reason not to leave trash behind at the beach.
This article first appeared in the UC Berkeley Wellness Letter.
Also see 29 Exotic Fruits to Try.