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"Food addiction" is becoming a popular term to explain overeating. But in this Scrubbing Up, Professor John Blundell from the Institute of Psychological Sciences at the University of Leeds warns the term is being used far too freely.
Some have likened food addiction to drug addiction, and then used this term to associate it with overeating, and as a clinical explanation for the obesity epidemic, implicating millions of people.
The use of the term food addiction is a step towards medicalisation and implies that normal human social behaviour is pathological.
Forms of eating therefore become an illness. This attitude is not helpful and has huge implications for the way in which people view their own behaviour and their lives.
The concept of food addiction comes from a combination of experimental data, anecdotal observations, scientific claims, personal opinions, deductions and beliefs.
It is an over-simplification of a very complex set of behaviours.
The existing evidence fails to define the precise characteristics of the actual foods concerned or the eating environment that underlies the assumed addiction risk.
I am concerned that many people may potentially latch on to the concept of food addiction as an excuse to explain their overeating”
This is in contrast to drug addiction, where the molecule is identified and its pharmacological effect on the brain is characterised.
Animal studies have shown changes to specific brain regions in those given a sugary diet - and human brain scans show activation of reward systems in the same part of the brain when sweet tastes are consumed.
Therefore, it is not surprising that reward centres are activated when sweet foods are consumed, as we know that the reward circuits in the brain have been established through evolution as signalling systems that control our appetite.
Many stimuli influence these areas of the brain and, in addition, there is an intrinsic drive to consume carbohydrate-rich foods to satisfy a basic metabolic need of the brain.
Sweetness is a major signal for such foods but the science has not yet assessed this fully and much more work is needed before we could say that food is addictive.
'Just an excuse'
Attributing food addiction as the single cause underlying the development of obesity, despite the existence of numerous other very plausible explanations, is unhelpful, particularly for those trying to live more healthy lives.
I am concerned that many people may potentially latch on to the concept of food addiction as an excuse to explain their overeating - the premise that it's "not my fault" and therefore, "I can't help it".
This removes the personal responsibility they should feel and could act on - and they infer that their eating is a form of disease.
Food addiction may offer an appealing explanation for some people but the concept could seriously hinder an individual's capacity for personal control.
Binge eating disorder does exist - but it is a rare clinical condition affecting fewer than 3% of obese people.
Sufferers have a strong compulsion to eat, which persists alongside the sense of a loss of control.
Addiction-like food behaviour may be a component of the severe and compulsive form of binge eating disorder.
But this condition does not explain the huge rise in obesity we have seen across the population.
Binge eating is not a key cause of obesity and, therefore, in the context of mass public health, is not a major concern.
What we need is a calm and composed analysis of what the words food addiction really mean so that people can make informed deductions about the causes of their own behaviour