Page 46 - BBC - The Scientific Guide to a Healthier You

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W e’re becoming more instead, it uses the same criteria used for any

obese, as a society.
addiction. This gives us a starting point, so
we can look at whether there are behavioural,
Is this because
cognitive or biological markers in this group.”
some of us are
addicted to certain
In one experiment, Dr Gearhardt showed
foods? One study, people pictures of ‘treats’ such as chocolate
at Connecticut College in 2013, suggested milkshakes, then gave them the real thing. She
that Oreos were “as addictive as cocaine”. found that people who have more ‘addictive-
Certainly, some people who are overweight like’ eating behaviour have more activity in
exhibit behaviours associated with addiction, brain regions linked to reward and desire when
such as an inability to avoid particular foods exposed to ‘addictive cues’ – the pictures of
and a tendency to over-eat at times of stress. But treats – than when they saw other images. They
this is not true of all overweight individuals. also have less of an inhibitory response in the
So does ‘food addiction’ actually exist? brain once they’ve drunk the milkshake than
To answer that, we first need to understand after consuming other non-addictive foods.
what addiction is. The Diagnostic and “This indicates that this group of people is
Statistical Manual very reactive to cues in
“The circuitry in the
of Mental Disorders the environment that
cites developing a suggest these foods
tolerance, becoming are available,” says
dependent and having brain that usually Dr Gearhardt. “When RIGHT: People who
withdrawal symptoms. they start consuming, completed the Yale
Food Addiction Scale
The latest version, allows people to apply the circuitry in the identified pizza as
DSM-5, added: “craving brain that usually the most ‘addictive’
food of all
the brakes and stop
or a strong desire or urge allows people to apply
to use a substance”. the brakes and stop BELOW: Modern diets
contain more sugar
Addiction affects eating may not be eating may not be than those enjoyed by
areas of the brain that working as well.” previous generations ISTOCK X2, SCIENCE PHOTO LIBRARY
are linked to pleasure, working as well” This same pattern BELOW RIGHT: Sugar
reward and decision- is also seen in people boosts dopamine
production and
making. It also affects with ‘conventional’ triggers the brain’s
reward pathways
neurotransmitters, the chemical signals used addictions. According to Dr Gearhardt, this
for communication between brain cells and further strengthens the case for food addiction.
brain regions. Over time, memory of previous In another study, Dr Gearhardt’s team recruited
exposures to rewards (such as food, sex, |RGQRNG VQ EQORNGVG VJG ;(#5 CPF VQ KPFKECVG
alcohol or drugs) leads to a biological response, which foods they were thinking of while
such as cravings. reading particular statements. The usual
The best tool that researchers have for suspects were at the top of the list: ice cream,
applying all this to food is the Yale Food chocolate, biscuits, sweets. According to Dr
Addiction Scale (YFAS). This 25-point Gearhardt, these are foods our brains have not
questionnaire was developed in 2009 by really evolved to handle yet.
Dr Ashley Gearhardt, an assistant professor
of clinical psychology at the University of SUGAR HIT
Michigan. She believes addictive processes Modern diets contain far more processed, sugar-
do play a role in eating-related problems. “My heavy food than those of previous generations,
research asks, how can we identify that group and it’s showing on our waistlines. NHS stats
of people who are most likely to be showing show the proportion of obese adults rose
an addictive response to food? The Yale Food between 1993 and 2013, from 58 to 67 per cent
Addiction Scale does not use bodyweight to in men and from 49 to 57 per cent in women.

identify people who could be addictive eaters; This is set to rise even further, predicts the

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