Probiotic Impact on Cognitive Performance, and Metabolic Outcomes in Overweight Young Adults With Impaired Glucose Regulation (ProCog)

Leeds Beckett University

Status: Enrolling

Conditions: Neurovascular Coupling Mechanism and Cognitive Function; Impaired Glucose Tolerance (Prediabetes); Cognitive Dysfunction; Overweight (BMI > 25); Impaired Glucose Regulation; Prediabetes (Insulin Resistance, Impaired Glucose Tolerance)

Treatments: Dietary Supplement: Lab4p Probiotic Consortium; Other: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT07073781

LBU-Lab4P-ProCogTrial-2025

i-NutriLife Hub PoC_R3_012 (Other Grant/Funding Number)

Details and patient eligibility

About

This 12-week, double-blind, placebo-controlled trial will examine whether daily supplementation with the Lab4P probiotic can improve cognitive performance and metabolic health in overweight adults aged 18 to 35 with impaired glucose tolerance, a preclinical condition where blood glucose regulation is mildly disrupted. Seventy participants will be randomly assigned to receive either Lab4P or a placebo. The study will assess changes in memory, executive function, and processing speed, along with blood glucose control, cardiovascular function, cholesterol levels, body composition, and markers of inflammation. The study will also analyse changes in the gut microbiome and evaluate the safety and tolerability of the probiotic.

Full description

Global rates of Overweight and obesity are rising at unprecedented levels, contributing to increased metabolic disturbances such as impaired glucose metabolism. Disruptions in glucose regulation are both characteristic of and contributory to the pathogenesis of metabolic disorders, including type 2 diabetes (T2D). Clinical perturbations in glucose homeostasis are strongly associated with cognitive impairments, and an increased risk of neurodegenerative diseases. Increasing evidence suggests that even slightly impaired glucose metabolism (IGM) may contribute to cognitive decline.

Emerging evidence shows that cognitive impairments, including memory, executive function, and visuomotor deficits, can be observed in young adults with impaired glucose metabolism, alongside early markers of structural and functional brain changes. Neuroimaging studies have revealed reduced white matter integrity and decreased cerebral glucose metabolism in prediabetic individuals aged 22-35, particularly in brain regions associated with attention, self-regulation, and working memory.

These neurocognitive effects appear to be driven by early neurovascular unit (NVU) dysfunction, involving elevated blood glucose, insulin resistance (IR), endothelial damage, and inflammation. Exaggerated glucose excursions promote oxidative stress and impair endothelial function at the blood brain barrier, disrupting cerebral blood flow (CBF), glucose transport and metabolic homeostasis. Functional uncoupling between CBF and regional cerebral glucose metabolism has been directly observed in young adults with IR.

Together, these findings suggest that NVU dysfunction may underlie early cognitive decline in young adults with IGM, and that this population represents a critical target for early, non-pharmacological intervention. Probiotic formulations, including the probiotic consortium Lab4P, have shown promise in improving metabolic markers and reducing inflammation, with preclinical data suggesting potential cognitive and neuroprotective benefits. However, its procognitive effects in humans remain unexplored.

This trial will evaluate whether Lab4P supplementation can enhance cognitive performance, and cardiometabolic regulation in overweight young adults with IGM. By targeting a modifiable risk state early in life, the study aims to determine whether probiotic supplementation can serve as a viable strategy to mitigate long term neurocognitive and metabolic decline.

Enrollment: 70 estimated patients

Sex: All

Ages: 18 to 35 years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria

• Aged 18-35 years
• Body Mass Index (BMI) between 25.0 and 29.9 kg/m² (classified as overweight)
• In good general health (self-reported)
• Normal self-reported sleep patterns, with no history of diagnosed sleep disorders
• Willing and able to provide informed consent
• Able to comply with study procedures, including fasting and oral glucose tolerance testing

Exclusion Criteria:

• Diagnosed diabetes (any type).
• Diagnosed sleep disorders.
• Fasting glucose >6.9 mmol/L during screening.
• History of bariatric surgery (e.g., gastric bypass, sleeve gastrectomy).
• Major surgery, significant illness, trauma, infection, or myocardial infarction within the past 6 weeks.
• Current use of medications affecting glucose metabolism or probiotics
• Pregnancy or actively trying to conceive
• Night shift work within the past month

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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70 participants in 2 patient groups, including a placebo group

Group receiving the Lab4P probiotic capsules

Experimental group

Description:

Experimental group will consume oral dose of 50 billion Colony forming Units (CFU) once daily till delivery.

Treatment:

Dietary Supplement: Lab4p Probiotic Consortium

Group receiving the identical, non-active placebo

Placebo Comparator group

Description:

Microcrystalline cellulose/d each, up till delivery

Treatment:

Other: Placebo