Sweet taste, appetite and obesity: Is there a link?
A presentation by Prof Kees de Graaf at the ISA Conference 2018
Sweet taste is conceived to signal the energy content of foods (assumption 1). As obese people ingest more energy, there is the intuitive notion that obese people have a sweet tooth (assumption 2) or ingest more energy from sweet tasting foods (assumption 3). These ideas circled around the popular press since the 1980’s and they still have a widely spread circulation in the societal discourse today. However, data have repeatedly shown that these assumptions are wrong.
In four recent studies, using data from the Australian (n=377 foods), Dutch (n=469), Malaysian (n=423) and American food supply (n=237), it was shown that perceived sweetness intensity did not correlate with the energy content of foods (r’s resp.: -0.08, 0.11, 0.04, and 0.11). Salt, umami and fat sensation intensity were better predictors of energy content.
Since the beginning of the 1980’s various studies with increasing numbers of subjects and more advanced methodologies showed that normal weight and obese subjects have similar sweetness preferences. In one recent study, in two independent Dutch subject populations (n=1351; n=944), we showed that the average contribution of sweet tasting foods to the overall energy intake is slightly lower in obese people (23%) than in normal weight people (26%).
When it comes to the role of properties of food in the regulation of appetite and food intake, it is advised to focus on the energy density and texture/eating rate of foods, instead of focusing on sugar and fat per se. Dozens of studies have repeatedly shown that food with a lower energy density and/or a lower eating rate lead to a lower energy intake.
Highlights from the ISA Conference 2018
The Science behind low calorie sweeteners: where evidence meets policy