Superlative benefits claimed
Over the years, a lot of produce has been given the ‘super’ label, usually over levels of antioxidants, but studies haven’t really made a clear case.
It’s expensive! It’s exotic! It’s superfruit! Meaning what, exactly? The term “superfruit” has been applied to acai berries, maqui berries, yumberries, chokeberries, goji berries, lingonberries, lychee berries — a lot of berries, in other words, but also baobabs, mangosteens, sea buckthorn, jujube fruit, cupuacus, pitayas, pomegranates ... the list keeps growing.
You may wonder what is it about these fruits that lifts them out of the ranks of the ordinary into exalted superfruit status. Superpr, that’s what. “‘Superfruit’ is just a marketing term,” says Gregory Cole, a professor of medicine and neurology at University of California at Los Angeles and associate director of research at the Greater Los Angeles Veterans Affairs Geriatrics Center. Still, if it conjures up the notion of fruits that have super powers for making you healthy, the marketers whointroduced it in 2005 would not be disappointed.
Those whobelieve in superfruit super powers generally say they come, in large part at least, from the antioxidants the superfruits contain. Claims of nutritional glories vary from superfruit to superfruit, but high antioxidant content is generally on the list, most likely at the top.
The logic seems simple enough: Antioxidants are good for you. Superfruits have more antioxidants than your average fruit. Therefore, superfruits are very good — super good — for you.
That conclusion requires a small leap of faith, namely, that if some antioxidants are good, more must be better. It’s not a leap that everyone is willing to make. We just don’t know enough, Cole says. There may be a limit to howmany antioxidants your body can absorb. Or maybe your body can absorb them all, but after a point, they don’t do you any more good — may even do you harm.
Acase in point: Aseries of recent studies at Kansas State University found that a super-abundance of antioxidants can actually interfere with proper muscle function.
Besides, fruits are more than just tasty antioxidant delivery systems. “They have a lot of different compounds with interesting medicinal properties,” Cole says. “But plants also make pesticides and anti-microbial compounds that may have toxic properties.” Rawalmonds are full of cyanide, and so are cherry pits and apple seeds, just to name a few disconcerting examples.
Researcher Barbara Hale is more supportive than Cole of the concept of superfruits, or “high polyphenolic fruits,” as she terms them. (This may explain why she’s a scientist at the Agriculture Department’s Humannutrition Research Center on Aging at Tufts University instead of an advertising copywriter).
Still, she agrees that antioxidants don’t tell the whole story. The antioxidant properties in superfruits come from their polyphenols, substances that give the fruits their color. But some polyphenols also have antiinflammatory properties, and Hale believes these may be just as important as their antioxidant capacities.
Blueberries garnered the first superfruit title after they were included in a bestselling book about 14 “superfoods” that could “change your life.” In short order, blueberries became quite possibly the most studied fruit in the world, and claims began to mount that they could keep you young, make you smart and cure just about anything that ailed you — or better yet, stop you from getting sick in the first place.
(In the rush to jump on the bandwagon, rules of logic weren’t always strictly enforced. For example, some concluded that blueberries improve night vision because bilberry extracts do, and blueberries and bilberries are cousins.)
Interestingly, blueberries may be contenders for superfruit of the year again in 2012. But not the blueberries you find at the store. In a study published last year, researchers reported on two species of wild blueberries native to Central and South America that they’re calling “extreme superfruits” because they have two to four times more antioxidants than the lowly has-beens you’re used to.
For the most part, the superfruit designation has gone to fruits that are unusual, and unusually pricey — qualities that, along with hard-to-pronounce names, can impart a certain cachet. (To become the pick of the superfruit crop, the extreme blueberries may need to go by their scientific names,
and Even among skeptics, there’s widespread agreement that most superfruits are probably good for you — though maybe not especially so. “Small trials may show that the upper-class fruits are better than placebos,” Cole says, “but are they better than the commonfruits?” That’s a hard question to answer, because the littlenobody fruits are often less likely than the high-end crowd to get research attention — and dollars.
“We can’t say anything about fruits we haven’t studied,” Hale says. “Who knows? Maybe the peach is the best thing out there. We don’t know, because we haven’t studied the peach.” Goji berry, mangosteen, baobab, maqui berry and acai all have been touted for good health. There could actually be some juicy advantages, studies have found. Here’s a look at a few items in the superfruit bowl.
Goji berry: Also known as wolfberry, this superfruit is actually a couple of closely related species native to southeast Europe and China. The fruits were dubbed “Duke of Argyll’s tea tree” in England after introduction there in the 1730s by (you guessed it) the Duke of Argyll. “Goji” is a relatively new name for these fruits, which look a tad like cherry tomatoes. Perhaps that’s no surprise — they are in the same plant family as tomatoes, potatoes and nightshade.
Mangosteen: Botanists aren’t sure where Garcinia mangostana L originally came from, though they suspect the tree hails from the Sunda Islands and the Moluccas of Indonesia. Mangosteen is grown extensively in Southeast Asia, and the fruit has a thick rind that has traditionally been made into tea to treat conditions such as diarrhea and bladder infections. The flesh inside is eaten as fruit.
Baobab: If you’ve seen the animated movie “Madagascar,” you’re familiar with the oddly fat-trunked baobab tree. Six of the eight species are unique to that island, but the fruit being incorporated into health foods and drinks comes from Adansonia digitata, which grows widely in sub-saharan Africa. In 2009, pulp from its 6-to-8-inch-long fruit was granted “generally recognized as safe” status by the FDA. An interesting baobab fact: The tree is pollinated by bats.
Acai: It’s the fruit of a palm tree that grows in Central and South America. The fruits make up a large portion — as much as 42 percent by weight — of the diet of some who live in the Amazon rain forest in Brazil. In a small study, blood sugar and total cholesterol levels fell in 10 obese adults eating acai pulp.