Neurocognitive, behavioural and physiological effects of non-nutritive sweeteners in humans

Lead Research Organisation: University of Manchester
Department Name: School of Medical Sciences


Obesity presents a major global health crisis; developing healthier diets is a key goal. However people eat for enjoyment and are therefore unlikely to simply choose to eat less, since hedonic drives may override homeostatic signals.

High calorie sugars form a large component of dietary excess; non-nutritive sweeteners (NNS) may be key to delivering palatable but less caloric foods. However there remains debate about NNS's impact on appetitive behaviour and energy homeostasis. The human gut responds to NNS differently than most animal models.

It remains unclear how behavioural and neurocognitive responses differ between ingested carbohydrates, such as sucrose and NNS. Until recently, studying the human brain regions receiving gut-to-brain signals was not possible. Recent advances in physiological functional magnetic resonance imaging have provided a new platform technology to map activity in these pathways and higher centres.

Using a combination of brain imaging (physMRI), neurocognitive/appetitive responses and physiology (gastric emptying, gut hormones, glycaemia), the project will build up a novel and integrated basis to understand the relationships between homeostasic status (physiological/metabolic signals) and hedonics (sweet taste, neurocognitive responses such as reward) and their impact on eating behaviour (incl. food selection) in response to caloric sugars or NNS.

As a CASE award recipient, the student will benefit from a 3 to 6 month placement at the Cargill R&D headquarters in Belgium (or Minneapolis R&D headquarters if preferred).

The successful candidate will acquire expertise in combining physiological and behavioural science, and be trained in the acquisition and analysis of human functional MRI data.


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Studentship Projects

Project Reference Relationship Related To Start End Student Name
BB/M011208/1 30/09/2015 31/03/2024
1792811 Studentship BB/M011208/1 30/09/2016 30/03/2021
Description Scientific advice is currently that sugar consumption should be limited to 5% of total dietary energy. This public health recommendation has led to a growing consumer and policymaker demand for limiting sugar content in a variety of foods and beverages, which has led to an increase in the consumption and use of non-nutritive sweeteners. However, it is evident that there are large gaps in our understanding of the effects of NNS in human health, appetite and body weight.
We explored the effects of consuming low-calorie sweeteners on appetite, food intake, cognitive and physiological responses associated with food cues. In a first acute single-exposure study we found that consuming a beverage sweetened with the low calorie sweetener stevia half an hour before lunch reduces appetite sensations similarly to caloric sugars (i.e. sugar) which further leads to reduced caloric intake during lunch time. When participants consumed the stevia beverage they consumed less calories in total (from the beverage and the meal) compared to when they had a water beverage prior to their lunch or caloric beverages.

Results from 2 more human trials exploring the physiological effects and the neural brain responses to the consumption of low calorie sweeteners in healthy adults are now being concluded.
Exploitation Route On-going debate concerns non-nutritive sweeteners (NNS) and their effects on health and body weight regulation. Findings from this research will contribute to our knowledge regarding the effects of non-nutritive sweeteners in humans and could potentially be used by public and private sectors to inform the consumers and to help the design and production of safe and nutritious products.

Results from this research could be exploited to secure further funding for the conduction of more human trials investigating the effects of NNS consumption on appetite, body weight and physiological responses in populations who would benefit the most by energy intake reduction and weight loss, such as diabetics type 2, individuals with metabolic syndrome etc.
Sectors Agriculture

Food and Drink