Enrolling by invitationNo phase

Brain Responses to Sweet Taste in Type 2 Diabetes and Prediabetes

Studies how sweet taste affects brain responses in adults with diabetes or prediabetes.

Key facts

Who runs it: University of Nottingham
Where: Nottingham, United KingdomSee the site
Trial code: NCT06804187
Registry title: Sweet Sensing in Type 2 Diabetes
Status: Enrolling by invitation
People taking part: 505 people, planned
Started: 1 Feb 2025
Planned end: Jun 2026
Type of study: Observational, 3 groups
Record updated: 8 July 2025

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults aged 18 to 60 with type 2 diabetes, prediabetes, or no diabetes. It studies how the gut and brain respond to sweet taste.

Age: 18 to 60 years
Sex: All sexes can join
Disease stage: Type 2 diabetes: HbA1c above 48 mmol/mol (6.5%), diagnosed within the last 10 years. Prediabetes: HbA1c 42-48 mmol/mol (6–6.5%), diagnosed at least 3 years ago. No diabetes: HbA1c 42 mmol/mol (6%) or lower. Phases 2 and 3 need right-handed people.
Earlier treatment: People with type 2 diabetes must be treated with metformin alone.
Biomarker or test result: HbA1c result checked within the last 12 months. Healthy volunteers without a recent HbA1c can be offered a screening blood test.

Main reasons for not taking part

Pregnant or breastfeeding (phase 1)
Insulin or any diabetes medicine other than metformin (phase 1)
Neurological or gastrointestinal disease or injury
Smokers
MRI contraindications such as metal implants, or unable to lie flat (phases 2 and 3)

The registry criteria, word for word

Show all 10 criteriaShow less

Who can take part

General Eligibility Criteria; For T2D: Confirmed Type 2 Diabetes Mellitus (HbA1c>48 mmol/mol (6.5%) and managed by the anti-diabetic drug metformin alone diagnosed within the last 10 years; For Prediabetes: HbA1c 42-48 mmol/mol and no less than 3 years since diagnosis; Non-diabetes who had HbA1c screened at their GP in the last 12 months: HbA1c≤42mmol/mol; Phase 1
Adults aged between 18 -60 years with type 2 diabetes or healthy individuals who had HbA1c checked within the last 12 months. Healthy volunteers who did not have HbA1c screened at their GP will be offered an opportunistic screening blood test
Phase 2 and 3:
right-handed adults between 18- 60 years with type 2 diabetes, pre-diabetes and healthy individuals who had HbA1c checked within the last 12 months. Healthy volunteers who did not have HbA1c screened at their GP will be offered an opportunistic screening blood test

Who cannot take part

Phase 1 exclusion criteria; Current pregnancy or breastfeeding; Current treatment with insulin or any other diabetic medications apart from metformin; History of neurological, gastrointestinal injury or disease; Any medication that is known to alter taste perception; Smokers; Phase 2 and 3 exclusion criteria
those who have contraindications to MRI including metal implants
those who have taken part in research projects within the last 3 months (projects involving administering a drug, invasive procedure i.e. venepuncture >50 ml, endoscopy, or exposure to ionising radiation)
individuals with Neurological or gastrointestinal disorders (IBD/ IBS)
those who are unable to lie flat
smokers

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

Are you between 18 and 60 years old?

Where in United Kingdom

University of NottinghamNottingham, United KingdomNo longer taking part

About the trial

What the trial wants to find out

Diabetes is a global challenge and the number of people affected by diabetes is expected to rise to 5.5 million by 2030, of which 90% are type 2 diabetes (T2D). Habitual high consumption of sugars is an important risk factor in the development, and progression, of type 2 diabetes (T2D). Several studies have now shown that individuals with T2D have reduced lingual sweet taste sensation and this in turns increases their sugar intake to achieve the same hedonic reward values compared to the healthy population. This subsequently will lead to development of diabetes or worsening of the blood sugar control.

Read full original descriptionShow less

Phase 1 of our study aims to identify the alterations in oral sweet taste sensitivity in individuals with type 2 diabetes and assess whether this is linked to sweet preference and habitual sugar consumption. In phase 2, we will use functional magnetic resonance imaging (MRI), a powerful technique used widely for diagnosing disease and investigating physiological and pathological process, to investigate whether diabetes or prediabetes status modulates activation of taste and reward-related brain responses to lingual sweet taste stimulation. Phase 3 will be investigating the reward-related brain responses to gut taste stimulation using functional MRI.

These new data will reveal the central mechanisms of sweet sensing in different status of diabetes and this will help develop novel treatment targets to improve metabolic and vascular outcomes in individuals with prediabetes or T2D.

The 3 groups in the trial

Type 2 diabetes group
Inclusion criteria right or left handed age between 18-60 years HbA1c \>48 mmol/mol duration of diabetes less than 10 years only for those who are treated with metformin excluding those with neurological disorder, gastrointestinal disorders, current pregnancy or breast feeding, on medications which can alter taste perception, current smokers, allergy to sugar, those who has contraindication to MRI, those who cannot lie flat, those who have taken part in research projects within the last 3 months
Prediabetes group
Inclusion criteria right handed individuals age between 18-60 years HbA1c between 42-48 mmol/mol, diagnosis of pre-diabetes not less than 3 years only for those who are treated with metformin excluding those with neurological disorder, gastrointestinal disorders, current pregnancy or breast feeding, on medications which can alter taste perception, current smokers, allergy to sugar, those who has contraindication to MRI, those who cannot lie flat, those who have taken part in research projects within the last 3 months
Healthy group
Inclusion criteria right or left handed individuals age between 18-60 years HbA1c \</=42 mmol/mol only for those who are treated with metformin excluding those with neurological disorder, gastrointestinal disorders, current pregnancy or breast feeding, on medications which can alter taste perception, current smokers, allergy to sugar, those who has contraindication to MRI, those who cannot lie flat, those who have taken part in research projects within the last 3 months