Clinical trial NCT06749327: Dissecting the Roles of High-quality Diets and Ultra Processed Foods on Cardiometabolic Health
Official title: Ultra-processed Foods, Diet Quality, and Cardiometabolic Health
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Cardiometabolic Risk Factors
Keywords: Plant-based diets
Diet quality
Cardiometabolic risk factors
Ultra-processed foods
Lead sponsor: Queen's University, Belfast
Sponsor class: OTHER
Collaborators: name: University College Dublin
name: Harvard School of Public Health (HSPH)
First posted: 2024-12-27
Enrollment: 330
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: Controversy remains around the role of ultra-processed food (UPF) consumption and health outcomes. A key question that remains to be answered is: when diet quality is the same, does food processing itself have any independent health effects? The current application aims to isolate the health effects of food processing from those of diet quality through the conduct of a dietary intervention study.

Detailed description: Controversy remains around the role of UPF consumption and health outcomes. A key question that remains to be answered is: When diet quality is the same, does food processing itself have any independent health effects?

The current study aims to isolate the health effects of food processing from those of diet quality through the conduct of a dietary intervention study.

To isolate the health effects of food processing, the investigators propose to use healthy plant-based diets as the "base" diet. The investigators propose to initially discover plasma metabolomic features responsive to improved hPDI adherence and then conduct a dietary intervention trial to evaluate the impact of UPF consumption, in the setting of a high hPDI diet, on cardiometabolic outcomes and metabolic pathways.

The study will consist of a run-in phase where participants with a low adherence to a plant based diet will be randomized into (1) an intervention group that will receive diet counselling to follow a high hPDI diet over a period of 6 weeks and (2) a control group that will consume their usual diet (low hPDI). Both arms will be advised to avoid ultra processed food (UPF) consumption. Assuming 15% attrition, the study will enrol 118 participants for the run-in phase. Individuals with a high adherence to plant based diet will follow their normal diet for the 6 weeks of this run-in phase and then will be randomised into the main 4 month study.

In the main four month study, a randomized controlled parallel group dietary intervention will be conducted in participants with high hPDI in Ireland (North and South) to evaluate the impact of UPF consumption, in the context of a high hPDI diet, on cardiometabolic outcomes such as glycated haemoglobin and total cholesterol, and metabolic pathways. Participants will be randomized into one of 2 groups: high UPF hPDI diet or low UPF hPDI diet. Assuming an attrition rate of 15%, the study will enrol \~212 individuals to achieve a sample size of 180 participants who will complete the trial.

Randomization will be performed using a randomization scheme generated using www.randomization.com with random block sizes by research staff independent of the study. The investigators will stratify randomization according to age and BMI.

Power calculation : Assuming a change in total cholesterol of 9 mg/dL at four months and assuming a SD of change of 20, a total of 78 participants in each group is needed. Allowing for participant dropout of 15%, which is similar to that observed in the investigator's previous interventions, gives an overall sample size of 180.

Based on an SD of difference in change in HbA1c of 0.3%, the same sample size could detect as statistically significant a difference in HBA1c of 0.15% between the two intervention groups at four months.

The total number of participants that will be enrolled will be 330: 118 (run-in phase) and 212 (4 month trial).

Eligibility criteria: Inclusion Criteria:

* Men and women aged between 18 and 65 years in general good health with BMI \< 35 kg/m2 who can provide informed consent.

Exclusion Criteria:

* Participants will be ineligible to enrol if they have diabetes, CVD, any type of cancer (except for basal cell skin cancer), or a condition (pregnancy, breastfeeding, etc) or dietary restriction(s) that would substantially limit their ability to complete the study.

Individuals will be screened for their adherence to the Plant based diet Index (PDI ).

1. Individuals with low adherence will enter run-in phase only (6 weeks)
2. Individuals with high adherence will enter the main intervention (4 months)

Primary outcomes:
measure: Glycated haemoglobin (HbA1C) (mmol/mol)
timeFrame: Baseline and 4 months
measure: Total cholesterol (mg/dL)
timeFrame: Baseline and 4 months
Secondary outcomes:
measure: Anthropometric measure: Weight (kg)
timeFrame: Baseline and 4 months
measure: Anthropometric measure: Height (m)
timeFrame: Baseline and 4 months
measure: Anthropometric measure: Waist circumference (cm)
timeFrame: Baseline and 4 months
measure: Anthropometric measure: Hip circumference (cm)
timeFrame: Baseline and 4 months
measure: Blood pressure (mmHg)
timeFrame: Baseline and 4 months
measure: Dietary assessment
timeFrame: Baseline and 4 months
measure: Physical activity
timeFrame: Baseline and 4 months
measure: Demographic/lifestyle information
timeFrame: Baseline and 4 months
measure: Continuous Glucose Monitoring (mmol/L)
timeFrame: Baseline and 4 months
measure: Plasma metabolome
timeFrame: Pre and post run-in phase (6 week run-in) ; baseline and 4 months (main trial)
measure: Gut microbiome
timeFrame: Baseline and 4 months
measure: Inflammatory markers e.g. CRP (mg/L)
timeFrame: Baseline and 4 months
Other outcomes:
Locations:
city: Dublin
country: Ireland
facility: University College Dublin
city: Belfast
country: United Kingdom
facility: Centre for Public Health, Queen's University Belfast
state: Northern Ireland
Study officials:
affiliation: University College Dublin
name: Prof. Lorraine Brennan, PhD
role: PRINCIPAL_INVESTIGATOR
References: