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DIET

B illed as the superheroes according to the International Food Information

The appetite for superfoods is growing –
of the culinary world,
Council, nearly nine in 10 Americans are
today, superfoods are as
widespread as comic-book
beyond basic nutrition. But they’re also
movies – every day it feels interested in foods that have health benefits
like a new one is being introduced. swallowing some unsubstantiated claims.
“There is neither a regulatory nor scientific Legends of doctors discovering remote
definition of a ‘superfood’,” says Dr Jeffrey mountain tribes of age-defying, goji-munching
Blumberg, from the Friedman School of Nutrition centenarians should self-evidently be taken
Science and Policy at Tufts University, Boston. with a large pinch of pink Himalayan salt –
“It is a marketing term that marketers do not another superfood with little scientific backing
RIGHT: Popular among
wish to define either.” But through an equally to elevate it above the table variety. But there’s celebrities from Madonna
unscientific survey of the books and blogs scarcely a grain of proof for the efficacy of the to Miranda Kerr, goji
berries have high levels
that liberally use the term, some common goji berry or any other superfruit. of certain nutrients
characteristics of these A Chinese study of 79 BELOW: Vegetables are
so-called superfoods The goji berry patients with advanced known to contain all sorts
of beneficial vitamins and
can be discerned. cancers found that their minerals. For example,
Superfoods typically boasts more conditions regressed kale has been found to
lower the risk of cancer
have high levels of when treated with goji and heart disease
certain nutrients, such vitamin C than polysaccharides, as well
as the goji berry, which as immunotherapy. But
boasts more vitamin C oranges, more information about the
than oranges, more beta design of the study and
carotene than carrots beta carotene the compounds used is,
and more iron than like evidence for the
spinach. Superfoods are than carrots majority of goji’s claims,
often exotic in origin – lacking. Another study,
the goji berry hails from and more iron on goji juice’s effects on

the Himalayas. “This brain activity, was only
seems to suggest that than spinach performed on 34 people,
they have some special and inconclusive at that.
health-promoting Most of the various
properties,” says Dr Blumberg. “Although studies related to goji and immunity, heart
the countries from which they come are disease and life expectancy have been either
not characterised by especially healthful or small or used concentrated extracts that would
long-lived people.” be unrealistic – not to mention costly – to eat
the equivalent of in real life.
BE READY TO FORK OUT
Superfoods are often rediscovered and FREE RADICALS
repackaged staples of ancient civilisations, Like many superfoods, such as blueberries
which also lends them credibility and a and açaí, goji berries are touted as being
quasi-mythical air, even though those ancient high in dietary antioxidants. “They act to
civilisations are long-dead. Like the goji berry, quench reactive oxygen, nitrogen and halide
which allegedly helped Chinese herbalist Li species, often called ‘free radicals’,” explains
Ching Yuen live to the ripe old (unverified) Dr Blumberg, who is also the senior scientist at
age of 256. Coincidentally, he also sold goji Tufts’ Antioxidant Research Lab. Free radicals
berries. Which leads us to perhaps their defining are commonly cited as causing cancer – according GETTY IMAGES

characteristic: they’re expensive. to the marketing, more antioxidants means less

22 BBC SCIENCE FOCUS MAGAZINE COLLECTION