58 | March• 2018
GUT BACTERIA – THE NEW FRONTIER OF SCIENCE
By mid-morning, he’s snacked on
a banana and a wholegrain muffin.
For lunch, he usually heads out to a
local café for a tuna salad sandwich
on brown bread and apple juice
(at 56, he’s always mindful of his
middle-age spread). The afternoon is
taken up with preparing reports and
meetings – and at least two trips to the
staff kitchen for more coffee plus a few
biscuits. By 5 o’clock, his thoughts are
turning to dinner –takeaway or make
a stir fry?he wonders. Deciding on the
healthy option, he cooks up some lean
chicken and a few vegetables, and fin-
ishes off with fruit and yoghurt.
By the time Jim climbs into bed and
drifts off to sleep, the activity in his gut
has reached fever pitch. Hundreds of
trillions of microscopic bacteria are
now busily breaking down the large
molecules in the food he’s eaten to-
day, converting it into fuel to power
him through the next day. Most active
of all is theLactobacillusandBifido-
bacteriumbacteria contained in his
yoghurt dessert, which have powered
their way to Jim’s large intestine, and
are vigorously breaking down the fibre
from his dinner vegetables, fending
off invasion from pathogenic species
and communicating with his immune
cells. The result of all this activity? Jim’s
immune system receives a boost, his
digestion operates like clockwork and
he enjoys a restful sleep. Come morn-
ing, he wakes up happy and alert.Your Internal War
Deep inside your belly, warring colo-
nies of micro-organisms are bracing
for battle. Every few days, entire pop-
ulations rise up or perish, supported
in their evolutionary struggle to sur-
vive by the food and chemicals you
feed them.
When you eat, you’re not just
feeding your body – you’re pro-
viding food for trillions of gut
bacteria. Weighing up to two kilo-
grams – a little more than the adul
human brain – these tiny creatures
breathe, feed and excrete, creating a
profound effect on the food you crave,
the state of your health and even how
you behave.
Some species thrive on certain types
of food, and others starve. This has im-
portant implications for your health.
For example, having more of certain
species ofPrevotellabacteria in the
gut – bacteria that love to eat carbo-
hydrates, such as sugar – is linked to
poor glucose tolerance and a higherLike many of us, Jim starts
hisworkingdaywithasimple
breakfastofasliceoftoastwashed
down with a cup of coffee.