36 LISTENER SEPTEMBER 14 2019
THIS LIFE
G
ET
TY
IM
AG
ES
Wholefood
helpers
The beneficial laxative
effect of rhubarb and
kiwifruit is about more
than just fibre.
Question:
People eat rhubarb to help stay “regular”. Do you know
if there is another factor, apart from fibre, causing this
effect?Answer:T
he start of spring heralds the arrival
of new rhubarb shoots in many
gardens. Although this vegetable is
traditionally served as a stewed dessert
in New Zealand, rhubarb is one of the
most ancient and important herbs in
Chinese medicine.
Rhubarb (Rheum rhabarbarum) has been eaten as
a food only relatively recently. British nurseryman
Joseph Myatt is thought to have been the first
to cook rhubarb with sugar, in the early 18th
century.
The leaves of the rhubarb plant shouldn’t be
eaten, as they contain poisonous substances such
as oxalic acid. In traditional Chinese medicine,
the roots of the rhubarb plant are prized for their
laxative effect and it has been a treatment for
constipation for thousands of years.
Those who eat the stewed fleshy stalks, or peti-
oles, of rhubarb may also have noticed something
of a laxative effect, too. It provides
a good helping of fibre,
with 2.4g per 100g of
stewed rhubarb, con-
tributing to the
recommended
daily intake of
25g for women
and 30g for men.But it is not rhubarb’s dietary
fibre that is credited with
promoting bowel
movements. Instead,
it’s a combination of
compounds known
as anthraquinones
that are thought
to be responsible.The compounds are metabolised
by gut bacteria, resulting in
increased bowel movements and
more water being retained in the
colon, leading to faster, looser
movements.
A 2017 study by Japanese
doctors found that among six
critically ill patients who hadby Jennifer Bowden
NUTRITION