Introduction
A common idea is that repeated exposure to sweet taste strengthens our preference for sweetness, which then drives greater intake of sweet foods and drinks. This idea is often used in arguments about fruit, low-calorie sweeteners, diet drinks, and the supposed need to “reset” taste preferences by avoiding sweetness altogether.
But does the evidence actually support that causal chain?
In this episode, Danny Lennon is joined by Prof. Katherine Appleton, Professor of Psychology at Bournemouth University, who discusses what is known about sweet taste exposure, sweet preference, and how these concepts are measured in the scientific literature.
- [04:23] Interview starts
- [07:35] Sweetness terms explained
- [10:17] Sweet liker phenotypes
- [14:03] Liking vs wanting vs preference
- [19:18] Trial evidence overview
- [23:48] Policy and practical impact
- [30:41] Why we eat foods
Episode Resources
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- Enroll in the next cohort of our Applied Nutrition Literacy course
- Relavant publications:
- Appleton et al., 2024 – Liking for Sweet Taste, Sweet Food Intakes, and Sugar Intakes
- Appleton et al., 2018 – Repeated exposure and conditioning strategies for increasing vegetable liking and intake
- Čad et al., 2026 – Effects of Non-Nutritive Sweeteners and Sweet Taste Exposure on Weight Management, Biomarkers of Health and Sweet Taste Preference
- Čad et al., 2026 – The Sweet Tooth Trial
Guest Information
Katherine Appleton, PhD is Professor of Psychology at Bournemouth University, with research expertise in human eating behaviour, nutrition, and public health. Her research focuses on understanding healthy and sustainable eating behaviours, and on developing and evaluating strategies to support dietary change in the general population.
Current areas of work include sugar consumption and sweet taste, increasing fruit, vegetable and legume intake, and nutrition and undernutrition in older adults. Professor Appleton is a Chartered Psychologist with the British Psychological Society and a Registered Nutritionist with the Nutrition Society.
Study Notes
Useful Terminology for this Episode
- Sweet taste exposure: The frequency, amount, or duration of encountering sweet-tasting foods or drinks.
- Sweet taste preference: A person’s relative liking for sweet taste, either in general or at a given intensity.
- Sweet liker phenotype: A sensory-science classification describing people who appear to prefer higher sweetness intensities.
- Sweetness intensity: The perceived strength of sweet taste in a food, drink, or experimental solution. A person may like sweetness but prefer it at a lower or higher intensity than someone else.
- Taste sensitivity: The ability to detect or perceive a taste stimulus. Differences in sensitivity mean that the same amount of sweetness in a product may be perceived as stronger by one person and weaker by another.
- Liking: The hedonic or pleasantness-based evaluation of a food or taste. A person may like a food even when they do not currently want to eat it.
- Wanting: The motivational desire to consume a food at a particular moment. Wanting is influenced by hunger, satiety, context, availability, expectations, and psychological factors, not only by sensory liking.
- Model foods: Experimental foods or solutions created to control sensory variables, such as sweetness, while reducing the influence of familiarity, branding, expectation, or previous experience.
- Sensory-specific satiety: A decline in desire to continue consuming a food with a particular sensory profile, while desire for foods with different sensory qualities may remain or increase.
Sweet Taste Exposure and the Assumption of Learned Preference
Key concept: The common narrative is that exposure to sweet taste leads to stronger preference for sweet taste, which then increases reward, desire, and intake. However, there is a lack of evidence for the first step in this chain: increased exposure to sweet taste does not appear to causally increase generalised sweet taste preference.
- A common assumption is that repeated sweet taste exposure trains people to like sweetness more strongly.
- This assumption is often used to argue against sugar, low-calorie sweeteners, diet drinks, and other sweet-tasting products.
- The proposed sequence is usually: sweet exposure leads to sweet preference, which leads to