Skip to main content
OpenTrials
Completed

NCT Number: NCT05628350

Highly Processed Foods and Vascular Health

Age is the primary risk factor for cardiovascular disease (CVD) and age-related vascular dysfunction is considered the key process linking the two. Middle age is a particularly vulnerable period when risk factors exceed diagnostic thresholds and clinical expression of CVD first becomes evident. Ultra-processed foods (UPF) comprise almost 60% of total energy in the standard American diet. The results of observational studies suggest that UPF consumption increases CVD risk, independent of overall diet quality (i.e., saturated fat, sodium, sugar, and dietary fiber intake). The "industrialized microbiota" may link diet, particularly UPF, to increased inflammation and CVD in middle-aged adults. High intake of UPF increases the likelihood of an excess heart age >10 years and doubles the risk of subclinical coronary atherosclerosis in middle-aged adults. However, the impact of reducing UPF consumption on vascular function in middle-aged adults is unknown. The overall objective of this study is to establish proof-of-concept for an improvement in vascular function following reductions in UPF consumption in mid-life adults, in order to conduct a larger, more comprehensive and mechanistic trial in the future. In addition, changes in gut microbial composition and function, intestinal inflammation and permeability, serum endotoxin concentrations, and inflammatory cytokines as potential mechanisms by which UPF consumption influences vascular function will be investigated.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Cardiovascular Diseases

Age range

40 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Virginia Polytechnic and State University

Blacksburg, Virginia, 24061, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Weight stable for previous 6 months (<2 kg change)
  • Sedentary to recreationally active
  • No plans to gain/lose weight or change physical activity level
  • Willing to pick up food daily and consume foods provided for an 8-week period
  • Verbal and written informed consent
  • Approval by Medical Director
  • Usual UPF intake +/-15% of US average of 60% total energy
  • Estrogen or testosterone usage is acceptable, if on stable dose for >6 months
  • Lipid-lowering medication usage is acceptable, if on a stable dose for >6 months

Exclusion criteria

  • BMI >35 kg/m2
  • Diabetes or diabetes medication
  • Antibiotic, prebiotic or prebiotic use in prior 3 months
  • Total Cholesterol >6.2 mmol/L; Triglycerides >4.5 mmol/L
  • Blood pressure (BP) > 159/99 mmHg (Stable BP on antihypertensive medications is acceptable)
  • Diagnosed inflammatory bowel disease
  • Past or current heart diseases, stroke, respiratory disease, endocrine or metabolic disease, or hematological-oncological disease
  • Vegetarian or vegan
  • Pregnant or plans to become pregnant
  • Food allergies or aversions
  • 3 or fewer stools per week or regular laxative use
  • Lipid-lowering medication usage <6 months

Treatment and study plan

No UPF controlled diet

Other

Following a two-week eucaloric lead-in diet, participants will be provided and consume a diet without UPF (0% total energy) for 6 weeks. Diets will be eucaloric (50% carbohydrate, 35% fat, 15% protein) and matched for dietary soluble and insoluble fiber, added sugar, mono- and polyunsaturated fat, saturated fat, antioxidant nutrients, sodium, pre- and probiotics, and overall diet quality.

HIgh UPF controlled diet

Other

Following a two-week eucaloric lead-in diet, participants will be provided and consume a diet with high UPF intake (81% total energy) for 6 weeks. Diets will be eucaloric (50% carbohydrate, 35% fat, 15% protein) and matched for dietary soluble and insoluble fiber, added sugar, mono- and polyunsaturated fat, saturated fat, antioxidant nutrients, sodium, pre- and probiotics, and overall diet quality.

Primary outcomes

  1. Change in brachial artery function from baseline to 6-weeks post no or high UPF diet

    Time frame: 30-minute measurement in the laboratory, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Flow Mediated Dilation (FMD) of the brachial artery will be assessed using duplex ultrasonography (GE Logiq e) with a high-resolution linear array transducer. Reactive hyperemia will be produced by inflation of a pediatric BP cuff around the forearm for 5 minutes. Offline analysis of baseline and post-reactive hyperemic diameters and velocities will be performed using edge detection software (Vascular Analysis Tools, Medical Imaging Applications, Inc). Endothelium independent vasodilation (EID) will be assessed by measuring brachial arterial dilation for 10 minutes following administration of 0.4 mg of sublingual nitroglycerine. Both FMD and EID will be expressed as mm and % change from baseline diameter.

Secondary outcomes

  1. Change in arterial stiffness (Carotid femoral pulse wave velocity) from baseline to 6-weeks post no or high UPF diet

    Time frame: 45-minute measurement in the laboratory, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Carotid femoral (C-F) pulse wave velocity (PWV), the primary measure of arterial stiffness, will be measured. C-F waveforms will be obtained via tonometry (NIHem, Cardiovascular Engineering, Inc). Aortic PWV will be calculated from signal averaged waveforms using the ECG as the fiducial point, and body surface measurements.

  2. Change in gut microbial composition from baseline to post 6-weeks no or high UPF diet

    Time frame: 3-day collection during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Stool samples will be collected daily for 3 days before and during the final 3 days of the diet interventions. Samples will be collected daily and placed in sterile plastic containers, stored in personal freezers, and placed in coolers for transport. Upon return to the lab, they will be immediately frozen at -80°C until final processing and analysis.

  3. Change in gut microbial function from baseline to post 6-weeks no or high UPF diet

    Time frame: 3-day collection during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Stool samples will be collected daily for 3 days before and during the final 3 days of the diet interventions. Samples will be collected daily and placed in sterile plastic containers, stored in personal freezers, and placed in coolers for transport. Upon return to the lab, they will be immediately frozen at -80°C until final processing and analysis.

  4. Change in intestinal inflammation from baseline to post 6-weeks no or high UPF diet

    Time frame: 3-day collection during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Intestinal inflammation will be assessed using fecal calprotectin, lactoferrin, and lipocalin-2, measured using ELISA.

  5. Change in intestinal permeability from baseline to post 6-weeks no or high UPF diet

    Time frame: 3-day collection during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Intestinal permeability will be assessed using serum zonulin (Immunodiagnostik AG, Bensheim, Germany) concentrations, measured using ELISA.

  6. Change in inflammatory cytokines from baseline to post 6-weeks no or high UPF diet

    Time frame: 5-minute blood collection in the laboratory, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Inflammatory cytokines, including Tumor Necrosis Factor alpha, Interleukin 6, and Monocyte Chemoattractant Protein-1, will be measured using ELISA (American Diagnostica Inc).

  7. Change in endotoxin from baseline to post 6-weeks no or high UPF diet

    Time frame: 5-minute blood collection in the laboratory, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Serum endotoxin will be assessed using the PyroGene Recombinant Factor C endotoxin assay (Lonza, Basel, Switzerland).

Other outcomes

  1. Change in insulin sensitivity from baseline to 6-weeks post no or high UPF diet

    Time frame: 2-hour test in laboratory, 2 timepoints (baseline, 6-weeks post no or high UPF diet)

    Insulin sensitivity assessed using a 2-hour oral glucose tolerance test (75g glucose load). Blood will be collected at baseline (fasting), and thereafter, at 30-minute intervals (5 total measurements in 2 hours).

  2. Change in 24-hour glucose control (24-hour mean) from baseline to 6-weeks post no or high UPF diet

    Time frame: 6-day measurement during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    24-hour glucose control (24-hour mean glucose concentration) will be assessed using continuous glucose monitoring for a 6-day period.

  3. Change in 24-hour glucose control (AUC) from baseline to 6-weeks post no or high UPF diet

    Time frame: 6-day measurement during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    24-hour glucose control (24-hour AUC) will be assessed using continuous glucose monitoring for a 6-day period.

  4. Change in 24-hour glucose control (time in range) from baseline to 6-weeks post no or high UPF diet

    Time frame: 6-day measurement during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    24-hour glucose control (time in range) will be assessed using continuous glucose monitoring for a 6-day period.

  5. Change in 24-hour glucose control (glycemic variability [GV]) from baseline to 6-weeks post no or high UPF diet

    Time frame: 6-day measurement during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    24-hour glucose control (GV) will be assessed using continuous glucose monitoring for a 6-day period.

  6. Change in 24-hour glucose control (postprandial glucose) from baseline to 6-weeks post no or high UPF diet

    Time frame: 6-day measurement during free-living, 2 timepoints (baseline, 6 weeks post no or high UPF diet)

    Free-living postprandial glucose concentration will be assessed using continuous glucose monitoring for a 6-day period.

Sponsors and collaborators

Lead sponsor

Virginia Polytechnic Institute and State University

Other

Collaborators

  • Duke University

Registry information

Official study title

Reducing Highly Processed Foods to Improve Vascular Health in Middle-Aged Adults

Important dates

Study start
2023
Primary completion
2024
Study completion
2025
First posted
Nov 28, 2022
Registry last updated
Jan 22, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.