"These results can contribute to more understanding about strong taste preferences in obesity," wrote lead author Kristina Elfhag from the Karolinska Institutet in Stockholm.
Over 300m adults are obese worldwide, according to latest statistics from the WHO and the International Obesity Task Force. About one-quarter of the US adult population is said to be obese, with rates in Western Europe on the rise although not yet at similar levels.
It has previously been suggested that food taste preferences varies between the sexes.
"It is a common notion is that the favourite foods of obese men are those high in fat and protein, whereas obese women rather chose foods high in carbohydrate/fat and sugar," explained Elfhag.
"According to our study on a rather small sample, there were no significant gender differences in sweet and fat preference. Our results suggest that the psychological factors override gender associations in taste preferences in obesity," she said.
The Swedish researchers recruited 60 patients at the Obesity Unit at the Karolinska University Hospital to undertake the study. Forty-four women and 16 men (average age 43.5, mean BMI of 40.1 kg per square metre).
The subjects were interviewed to gauge preferences for sweet and/or fat foods. Eating habits were measured used the Three Factor Eating Questionnaire (TFEQ), and personality traits were analysed using the Swedish universities Scales of Personality (SSP).
It was found that 27 per cent of the subjects preferred sweet tastes only, 28 per cent preferred fat tastes only, and 10 per cent reported liking both.
When preferences were compared with scores from the eating behaviour analysis and personality tests, the researchers found that fat taste preferences were associated with low levels of cognitive restraint over eating.
"is means obese patients who are not prone to make conscious attempts to control and restrict their food intake have more preference for fatty foods. This could be due to a lower ability to resist foods among those who have a strong liking for fat," suggested the researchers.
Strong preferences for sweet tastes were linked to high scores for the personality dimension neuroticism, namely "lack of assertiveness" and "embitterment".
This observation appears to agree with both animal and human studies that reported that sucrose could reduce the effects of chronic stress by reducing the activity of the Hypthalamo-Piuitary-Adrenal (HPA) axis in the brain.
"Chronic stress leads to elevated glucocorticoids which in turn stimulates the drive for "comfort food" (sucrose)," said Elfhag.
There are some limitations with this study, namely that sweet preferences included foods such as chocolate, ice cream and pastries, which could more accurately be described as "sweet-fat foods". However, this limitation is itself limited by suggestion that sugar masks the taste of fat.
These results do have some tentative clinical implications, said the researchers.
"For the obese patient with a strong sweet taste preference, there could be reason to focus on the psychosocial situation and the psychological factors in eating. For the patient with a strong fat preference, we rather need to understand more about the link to their eating behavior," concluded Elfhag.
The study was published in the June 15th issue of Physiology and Behavior (Vol. 88, pp. 61-66).