24 BBC SCIENCE FOCUS MAGAZINE COLLECTIONDIETexpectations of what they will do. “I prefer
the concept of ‘high nutrient density’ foods,
which is a central theme in the new 2015-2020
dietary guidelines for Americans,” says Prof
Nieman. “The term ‘superfood’ is not used
by most scientists because the implication is
that one can expect quick and high-end health
benef it s.” By a l l mea ns, spr i n k le some c h ia seeds
on your oatmeal. You’ll get a nutritional boost,
but you won’t instantly become an Olympian
athlete. “What matters is the habitual eating
pattern over years,” says Prof Nieman.A BALANCED DIET
By seeing superfoods as a magic bullet, we risk
shooting ourselves in the foot.
“Some people think if they eat one ‘superfruit’,
they don’t need to eat the other recommended
four servings of fruit a day,” says Dr Blumberg.
But no one superfood is a panacea – nor
will it make up for other deficiencies. “Adding
superfoods to a good diet is fine,” says
Dr David Katz, director of Yale University’s
Prevention Research Center. “Counting on them
to compensate for a bad diet is not.”
Undue emphasis on superfoods can be
unhealthy. “The term helps companies
sell product, and it ‘helps’ consumers
oversimplify their diets,” says Patel.
All the experts cited here stressed
the importance of consuming a wide
variety of natural, ‘whole’ foods, which in
turn reduces their individual significance.
“No single food or beverage is important
enough to stand out from the overall lifestyle,”
points out Prof Nieman.
Another unintended consequence of the
fashionable superfood label can be felt in 5The problem is not that
superfoods are a con – many
are highly nutritious – but
calling them ‘super’ gives
us unrealistic expectations
5 “Plus, our body’s own antioxidant systems- involving compounds like glutathione – are
more powerful than what we can get from food.”
TRICKY TO STUDY
The proof of the superfood pudding is in the
eating... by humans, not mice or rats. But
unfortunately, most scientific research is not
conducted this way. “Nutrition studies often
don’t apply to real life on a 1:1 basis,” says
Patel. “If you want to test, say, the effect of
grape juice on cognition, you’d give it enough
time, plus you’d check to make sure they
ac t ua l ly d r i n k it. I n rea l l ife, t hat a l most never
happens.” Lifestyle factors are difficult if not
impossible to separate. And there are other
problems, says Patel – pilot studies and animal
trials will often use larger dosages, while ‘acute’
studies will look at just the food without any
other things consumed. Meanwhile, eating
different foods together, which is what most
of us do, can dramatically alter their effects
for better or worse.
Another issue affecting superfood research
is that it is often paid for by interested
parties. “We’re funded by food and supplement
companies in many of the studies we conduct,”
admits Prof David Nieman, director of the
Human Performance Labs at Appalachian State
University in North Carolina. “But the system
demands contractual agreement that gives
the primary investigator ‘academic freedom’,
or the right to publish the data, positive or
negative. Many of the companies I work with
are so convinced that their product has special
effects that they sign these agreements.”
What buyers should beware of are
studies conducted in-house by
companies, which are “close to
worthless”, says Prof Nieman. But
while industry-funded doesn’t mean
false, the anointed superfood might
not be much better than a cheaper
equivalent that doesn’t have the
same commercial imperative (see
‘Everyday heroes’, page 26).
The problem is not so much that
superfoods are a con – many of them, such as
chia seeds or kale, are highly nutritious – more
that calling them ‘super’ gives us unrealisticThe blueberry is often
referred to as the
‘grandaddy’ of the
superfood movementGETTY IMAGES