Sweet Disposition: Individual, population and global positionings of sweet taste.

Abstract

The narrative that a greater exposure to sweet taste would increase the preference for sweet taste and consequently, increase sugar intake and lead to a higher prevalence of negative health outcomes, remains unproven and unclear; even though it sets the parameter for numerous sugar reduction recommendations. This thesis, therefore, aimed to explore the entirety of sweet taste in dietary intake and health outcomes, at the individual, population, and global levels. A randomised controlled trial was designed to assess the adaptability of sweet taste preference through dietary intervention with varied sweet taste exposures. Dietary sweet taste exposure at baseline showed no association with sweet taste preference, nor with indicators of obesity and Type 2 diabetes. Notwithstanding, focus groups identified possible attitudes towards sweet-tasting foods, sugar, and sweeteners, towards their consumptions and towards related policies, in a small sample of the general public in the United Kingdom (UK). Individuals varied in their perceptions, motivations, and concerns towards these food items. A structured questionnaire was then developed to assess associations between attitudes and intakes, and to identify individual characteristics that may influence the prevalence of attitudes. Individual variations in attitudes remained in this larger sample of consumers. Individuals who felt they could manage their intakes, added sugar and consumed sugar food groups and total sweet-tasting food groups more frequently; individuals who felt they were unaffected, also consumed sugar food groups and total sweet-tasting food groups more frequently. Three latent sub-populations with distinct combinations of attitudes of different strengths were identified: feeling ill-equipped, actively engaged or unopinionated. Moreover, approaches to quantify sweet taste exposure in the diet, amongst other tastes, were evaluated for their suitability and feasibility to characterise dietary taste exposure patterns in and across populations. These taste exposures and patterns were subsequently compared between Australia, France, the Netherlands, the UK, and the United States (US). While the diets within the countries mostly had similar taste combinations, they differed in the percentage contributions from these clusters to total energy intake. They also differed in their absolute dietary taste exposure, although some of their patterns displayed similarities, such as dietary sweet taste exposure contributing the most to total exposure in the diets of Australia, the UK, and the US. This thesis challenged the common narrative of ‘sweet taste exposure – preference – sugar intake – health’, by looking at the direct relationship between exposure and preference, and health. It provided insights into individual, population and global variations in dietary sweet taste exposure and attitudes towards and intake of sweet taste. While further investigation into the adaptability of sweet taste preference and the aforementioned associations in more representative samples is required, this thesis highlighted the value for segmentation and prioritisation of specific sugar reduction strategies in distinct sub-populations.