Towards a diagnosis of food addiction?

A global obesity crisis, regularly warned of by the World Health Organisation (WHO), is developing in Europe and throughout the world. Increased consumption of rich foods, particularly those rich in sugar, has been singled out as a major factor in this epidemic. A loss of control over food intake and the general concept of food addiction have been studied by a team of researchers from Bordeaux. Their work was recently published in the journal Drug and alcohol dependence.

While it may seem obvious to talk about addiction in relation to eating disorders (EDs), this has not yet been scientifically demonstrated, points out Marc Auriacombe, Professor of psychiatry and addictology, Director of the SANPSY* laboratory and co-author of the study. "There are still different schools of thought on this subject".
In fact, in the Diagnostic and Statistical Manual of Mental Disorders (DSM), the international reference work describing and classifying mental disorders, the most severe eating disorders - anorexia nervosa, bulimia nervosa and binge eating disorder - are in a separate category, and not considered to be addictions. This may have led to attempts to treat these mental pathologies by trying to modify behaviours without understanding them. Trivially, by trying to encourage anorexics to eat and bulimics to eat less. But if EDs were classified as addictive behaviours, appropriate treatment could be provided on a widespread basis.

An inevitable loss of behaviour control

The researchers carried out a study on patients consulting for obesity or an addictive disorder (not necessarily food-related, but which could be linked to alcohol, for example). Diagnostic criteria were assessed using the mini International neuropsychiatric interview (IRT) adapted to food addiction during individual interviews. A total of 508 patients aged between 18 and 70 from the Centre spécialisé de l'obésité (Specialised obesity centre - CSO) at Bordeaux University Hospital and the Centre de soins d'accompagnement et de prévention en addictologie (Addiction care, support and prevention centre) at Charles Perrens Hospital were included in the study.

The results show, for the first time, the validity of an eating disorder, as defined by the 11 criteria set out in the DSM-5 classification of addictive behaviours (in French), with the craving criterion as the most discriminating. A signal is triggered that leads patients to eat when they don't want to at that moment. It's not just a simple craving that can be adjusted from one time to the next, thanks in particular to the memory that reminds them not to overindulge in this or that food. There is a loss of behaviour control, which is difficult to avoid.

For Marc Auriacombe, "these results support the inclusion of an 'eating disorder' module in future versions of the DSM. Whether or not we should leave eating disorders in a separate category, or create a sub-category of addictions, is still open to debate. But this has major implications both at clinical level and in terms of public health policy in the context of the global obesity epidemic. By taking addiction into account, we can act at the right level of behavioural dysfunction, detecting it as early as possible to avoid the onset of severe disorders.

These results concern adults only. The question of childhood obesity merits further exploration, explains the researcher. The expression of an addiction in a child, which is still developing, raises other questions that have yet to be resolved.

This research follows on from the work on screen addiction already published last year by the same team. The only behavioural addiction currently listed in the DSM 5 is gambling addiction.
The study was led by the SANPSY unit and the Charles Perrens Hospital, in collaboration with two other Bordeaux Neurocampus units, the Magendie neurocentre and the Institut de neurosciences cognitives et intégratives d'Aquitaine (INCIA), and with Bordeaux University Hospital and Columbia University in New York (specialists in the IRT method for analysing data).

* SANPSY laboratory - Sommeil, addiction, neuropsychiatrie (CNRS and University of Bordeaux)