Photographer:Fotograaf: Joey Roberts/ Simone Golob
Who believes in the myth that dieting makes you fat? Nobody, isn't it? “There are frequent statements in international media that dieting encourages overeating and therefore makes you fatter. But that is an error of reasoning,” says Anita Jansen, professor of Experimental Clinical Psychology and dean of the Faculty of Psychology and Neurosciences. “What we see is that there is a difference between wanting to eat less and actually eating less. Many dieters want to lose weight but often don’t succeed in staying away from all kinds of tasty goods or reducing their portion sizes.” Jansen refers to them as “self-defined dieters. Often, they even have a higher BMI than non-dieters. The only predicting factor as to whether a diet will work, is if you stick to it, compliance.”
More than 50 per cent of the world population is overweight, having a BMI above 25. People who are overweight often have a whole list of excuses: it is in the genes, their bones are heavy, or it is the outside world’s fault, seducing them will sweet and savoury snacks. “But they have to learn that they can actually resist food.” And that requires the right supervision by a behavioural scientist. This is not an easy task because in general people who are obese turn out to be more impulsive. “At parties, they have a little bite here and a little bite there, because everyone is having a great time and tomorrow is another day. They are often less able to restrain themselves.” But experiments have shown that this can be learned. “It is possible to teach people to eat less in two one-hour sessions. We let test cases smell delicious food in our lab and then have one little bite, for longer periods. That is often enough to become slightly satisfied, to quench the appetite and thus to eat less. Exactly how this process works, why one can become satisfied by smells, is still unclear.”
According to Jansen, 67 per cent of a person’s weight is genetically determined. But the fact that your father and grandfather were overweight, doesn’t mean you have to accept this as your destiny. “We accept that depressed people have therapy and learn to deal with their ‘genetic components’, but we don’t do so with obese people.” Many of them end up in an operating room for a gastric band. And it is true, these interventions often do the job, the weighing scale indicates fewer kilos, “but it is still external control”.
What does Jansen suggest? “First and foremost: cognitive behavioural therapy is already a common approach in clinics treating eating disorders, but the ‘treatment’ for obesity is still focussed primarily on giving advice, to change one’s lifestyle. It should be about changing behaviour, for example, being able to resist temptations.” She refers to the practice of reducing cue reactivity: repeated exposure to food without eating, resulting in loss of appetite. “We once compared two groups: successful and unsuccessful dieters. What did it show? The unsuccessful dieters secreted a lot of saliva when they saw delicious food; the ‘successful’ ones produced less saliva. We assume that the latter had managed to break the habit of their bodily reactivity in a cognitive manner.”
Jansen and her colleagues, also referred to as Maastricht University’s eating group, work closely with mental health care institute Virenze Riagg. They are trying to apply effective techniques in the clinic. The eating researchers have also developed a number of iBooks to help improve obesity treatment in health care. She emphasises that cognitive behaviour therapies are meant for professional staff, they are not self-help books.
Obesity is not described in the DSM, the handbook for psychological disorders, and hence obese people are not eligible for the mental health care treatment. “This is only possible if there is an eating disorder.” Jansen is an advocate of treating obesity – “only for those who have problems with it and are seeking help“ – as a behavioural disorder in mental health care.
This is a series in which academics shoot down popular myths