Abstract
It is widely believed that exposure to sweetened foods and beverages stimulates the liking and desire for sweetness. Here we provide an updated review of the empirical evidence from human research examining whether exposure to sweet foods or beverages influences subsequent general liking for sweetness (‘sweet tooth’), based on the conclusions of existing systematic reviews and more recent research identified from a structured search of literature. Prior reviews have concluded that the evidence for a relationship between sweet taste exposure and measures of sweet taste liking is equivocal, and more recent primary research generally does not support the view that exposure drives increased liking for sweetness, in adults or children. In intervention trials using a range of designs, acute exposure to sweetness usually has the opposite effect (reducing subsequent liking and desire for sweet taste), while sustained exposures have no significant effects or inconsistent effects. Recent longitudinal observational studies in infants and children also report no significant associations between exposures to sweet foods and beverages with measures of sweet taste preferences. Overall, while it is widely assumed that exposure to sweetness stimulates a greater liking and desire for sweetness, this is not borne out by the balance of empirical evidence. While new research may provide a more robust evidence base, there are also a number of methodological, biological and behavioural considerations that may underpin the apparent absence of a positive relationship between sweetness exposure and liking.
Summary
The aim of this study was to review the empirical evidence testing the relationship between sweetness exposure and subsequent liking in adults and children.
Authors followed a systematic approach to identify recent studies that measured or intervened in exposures to sweetened foods and beverages and reported an explicit measure of sweetness liking after exposure. The review included human clinical trials and prospective cohort studies published between August 2017 and February 2024 and follows up on previous systematic reviews on the topic, which have consistently concluded that the available evidence did not support the notion that sweetness exposure enhances a ‘sweet tooth’.
Among the eleven studies retrieved that assessed acute or sustained sweetness exposure, none reported increases in measures of sweet taste liking. Four trials examining the effects of exposure to sweet versus non-sweet products followed by an assessment of sweetness liking or choice within the same product format produced mixed results. Overall, they showed no significant effect of sweetness exposure, with inconsistent differences between exposures to low/no calorie sweeteners (LNCS) and sugar. Three cohort studies in infants and children reported no significant associations of exposures to sweetness with measures of sweet taste preferences.
Taken together, recent research is in line with earlier systematic reviews and does not support a relationship between sweetness exposure and subsequent liking for sweet taste. The present conclusions are similar for research in adults and children, LNCS and sugars, and from both intervention and cohort studies.