32 LOSE IT! VOLUME 30
weren’t physically hungry, your
body gave you the signal to eat. In
these situations you know you’re
not ‘supposed’ to be eating, but
your body continues to send you
the signals. As a result you find
yourself gorging on high-carb
or sugary snacks – chomping
on cucumber sticks or a piece
of biltong simply won’t do the
trick. Your body prefers to use
carbohydrates or glucose as its
primary fuel, so if you are eating
a high-carbohydrate diet (or have
been in the past), your body will
first try to utilise
the carbohydrate
before tapping into
calories from fat
or protein. And so
the vicious cycle
continues. The more
refined carbohydrates
you eat, the more
your energy levels
fluctuate between
high and low
throughout the day.
So what you’re
doing is going from
one meal to the next- with several snacks
in between – and never truly
feeling like you are running on
‘real’ energy. You’re merely trying
to prevent yourself from running
on empty.
To make matters worse,
regardless of how little you eat,
it becomes extremely difficult to
tap into your fat stores if you’re
trying to lose weight.
If you eat a diet high in sugar
and simple carbohydrates your
body will prompt you to continue
eating these foods, which will
keep you hungry and craving
carbs. Often the craving is so
intense that it feels impossible
to ignore.
GHRELIN
This hormone is produced in your
stomach and secreted when it is
empty. It enters the bloodstream
and affects a part of the brain
known as the hypothalamus,
which governs your hormones and
appetite. Ghrelin levels typically
rise before a meal, when your
stomach is empty, and decrease
shortly afterwards when your
stomach is full. Irrespective of
how much body fat you have,
ghrelin levels
increase when
you start a
diet, leaving
you feeling
hungry and
‘deprived’.
This is a
natural
response from
your body,
which tries
to protect
you from
starvation.
Within a
couple of days
of starting a diet your ghrelin
levels will rise and continue to do
so over the course of a few weeks,
which will leave you hungrier and
make it a lot more challenging to
maintain any weight loss.Leptin is essentially the antithesis
of ghrelin. It’s often referred to as
the ‘fullness hormone’. Its primary
job is to send signals to your brain
to let you know you are full or
satiated, and that you should stop
eating. At the same time leptinLEPTIN
sends signals to your brain
to ‘turn on’ your metabolism
and thus start converting food
to energy.
As leptin levels rise, you
will be less hungry; as leptin
levels decrease, you feel hungrier.
Likewise, rising leptin levels will
increase your rate of metabolism,
while falling levels will slow your
metabolism.
So if this hormone is so finely
tuned, why do we struggle
with hunger/satiety signals and
continue to gain weight?
According to Dr Robert
Lustig, Professor of Paediatric
Endocrinology at the University
of California, the problem is
that although overweight people
have large amounts of leptin,
their brains aren’t getting the
important signal to stop eating
because of something called leptin
resistance. Leptin resistance is
similar to insulin resistance, in
which the pancreas produces large
amounts of insulin, but the body
doesn’t respond to it properly.
Leptin levels continue to rise
as people gain weight. ‘We all
have a leptin floor; the problem
is, we don’t have a leptin ceiling,’
explains Lustig. ‘In leptin
resistance, your leptin is high,
which means you’re overweight if
not obese, but your brain can’t see
it. In other words, your brain is
starved while your body is obese.
And that’s what obesity is: it’s
brain starvation.’None of this is particularly
encouraging. The idea that
your brain could be sabotaging
your weight loss efforts is rather
depressing! Fortunately, there are
steps you can take to keep these
hormones in check. See the
table on the next page. ➽