To review research that tests the validity of the analogy between addictive drugs, like cocaine, and hyperpalatable foods, notably those high in added sugar (i.e., sucrose).
Available evidence in humans shows that sugar and sweetness can induce reward and craving that are comparable in magnitude to those induced by addictive drugs. Although this evidence is limited by the inherent difficulty of comparing different types of rewards and psychological experiences in humans, it is nevertheless supported by recent experimental research on sugar and sweet reward in laboratory rats. Overall, this research has revealed that sugar and sweet reward can not only substitute to addictive drugs, like cocaine, but can even be more rewarding and attractive. At the neurobiological level, the neural substrates of sugar and sweet reward appear to be more robust than those of cocaine (i.e., more resistant to functional failures), possibly reflecting past selective evolutionary pressures for seeking and taking foods high in sugar and calories.
The biological robustness in the neural substrates of sugar and sweet reward may be sufficient to explain why many people can have difficultly to control the consumption of foods high in sugar when continuously exposed to them.
aUniversité de Bordeaux
bCNRS, Institut des Maladies Neurodégénératives, Bordeaux, France
Correspondence to Serge H. Ahmed, Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, 146 rue Léo-Saignat, F-33000 Bordeaux, France. Tel: +33 557 571 566; fax: +33 556 900 278; e-mail: firstname.lastname@example.org