JUNE 8 2019 LISTENER 37
There is growing interest in the
role kiwifruit may play in diges-
tive health. In addition to fibre,
the Hayward variety contains
actinidin, a natural enzyme that
breaks down a range of food pro-
teins faster than our own digestive
enzymes. Red kiwifruit also have
moderate amounts of this activity.
The fruit have a mixture of insolu-
ble and soluble – water-retaining
- fibres, which help create a larger,
softer stool that moves more quickly
through the digestive system. A
University of Otago clinical trial
found that constipated people who
ate two green kiwifruit a day had
two more bowel motions a week and
G
ET
TY(^) IM
AG
ES
SCIENCE AND NATURE BRIEFS
Email your
nutrition questions
to nutrition@listener.
co.nz
RISE IN RISING TIDE ...
Global sea-level rise could be higher than
previously predicted, because of the
accelerated melting of Greenland and Antarctic
ice sheets. New research doubles estimates
that sea levels will rise 1m by 2100, believing
that a rise between 62cm and 2.38m is possible,
depending on our immediate climate actions. In
this potential scenario, the average temperature
would increase 5°C, and hundreds of millions of
humans and animals would die or be displaced.
... BUT BEDBUGS COULD SAVE US
Researchers scouring caves, cliffs and museums
for bedbugs have found the insects originated
at least 100 million years ago. This challenges
the current dating for the tiny parasites, and
places them in the Late Cretaceous period
when dinosaurs roamed the Earth. The
scientists may use their survival methods as
ways to adapt to the effects of climate change.
A RUN ON COFFEE
Coffee makes mischief with a rat’s gut, US
researchers say. It inhibits microorganisms and
stimulates intestinal contractions, regardless of
its caffeine content. However, a stronger brew is
more of a gut-bacteria suppressant. University
of Texas scientists say further work is needed
to see whether “good” or “bad” bacteria are
affected and if coffee can cure constipation in
people who have had abdominal surgery.
ABSORBING READING
Don’t feel guilty about that pile of unread
books on your bedside table. Researchers
from the Australian National
University, in Canberra,
have found just
being around books,
even when unread,
is beneficial and can
enhance intellectual
capacity later in life.
People who grew up
in a home with a large
number of books have
better literacy, numeracy,
technology skills and
problem-solving skills
than those with few books
in their childhood home,
even when the compared
children had a similar
education and grew up to
have similar jobs. This can be
attributed to the phenomenon
known as the radiation effect, as
well as exposure to adults valuing
books and literacy knowledge.
less gastrointestinal discomfort.
Another recent New Zealand
clinical trial found that eating two
SunGold kiwifruit daily for 12 weeks
significantly raised plasma vitamin
C levels in prediabetic study partici-
pants, and led to small improvements
in several markers of metabolic and
cardiovascular health. For instance,
there were noticeable reductions in
both diastolic (4mmHg) and systolic
(6mmHg) blood pressure, as well as
in waist circumference (3.1cm) and
waist-to-hip ratio.
Previous clinical trials have also
produced good results: four gold
kiwifruit a day over four weeks
significantly reduced the severity and
duration of cold symptoms; and two
gold kiwifruit a day with an iron-
fortified breakfast cereal eaten by
women with low iron levels resulted
in better iron stores after 16 weeks
compared with eating the same cereal
with banana.
Green kiwifruit have also been
shown to slow the absorption of
sugars from an accompanying
breakfast cereal, thereby reducing
undesirable blood-sugar spikes.
Aside from being a
nutritional powerhouse,
kiwifruit are read-
ily available almost
year-round, being
sold from April
to January.
Depending on
the outcome
of Zes-
pri’s trial,
increasing
numbers of
them may
be red. l
The red fruit contain
an anthocyanin, which
is responsible for
their colour and has
antioxidant effects.