NCT06976112 · Pennington Biomedical Research Center
Impact of Lean Pork on Endothelial Function in Perimenopause
(LEAP)
What this study is about
The goal of this study is to examine the impact of a diet high in fresh lean pork, compared to a plant-based diet, on cardiovascular function and vasomotor symptoms in perimenopausal women with overweight and obesity. The main questions it aims to answer are: 1. How does a diet high in pork, compared to a plant-based diet, affects blood lipids, endothelial function, and blood pressure? 2.
View original scientific description
The goal of this study is to examine the impact of a diet high in fresh lean pork, compared to a plant-based diet, on cardiovascular function and vasomotor symptoms in perimenopausal women with overweight and obesity. The main questions it aims to answer are: 1. How does a diet high in pork, compared to a plant-based diet, affects blood lipids, endothelial function, and blood pressure? 2. How does a diet high in pork, compared to a plant-based diet, affects blood nitrate, cardiometabolic biomarkers, inflammatory biomarkers, and vasomotor symptoms? Researchers will compare the diet high in pork to a plant-based diet to see if pork helps improve cardiovascular and mesopause symptoms. Participants will: * Consume both of the diets, each for 4 weeks, with a washout period between 2 and 6 weeks in between the diets trials * Visit the clinic 5 times with weekly meal pick ups during the diet trials * Undergo testing procedures including: weight and body composition, blood pressure and pulse, endothelial function using ultrasound of upper arm, microvascular blood flow, blood draws, physical activity measurements, and questionnaires.
Interventions
BEHAVIORAL
Pork Diet
The diet will follow the Dietary Guidelines for Americans with 80% of the meat consumption per week being pork. Other animal protein (e.g., turkey, chicken, beef) will be minimized in the dietary plans (≤ 20%) so lean and processed pork are the primary protein source consumed. Within each day, \~80% of the daily pork intake will be fresh, unprocessed lean cuts (e.g., tenderloin, loin chops, sirloin roast, flank, and rump roast) and \~20% will be cured sources (e.g., Canadian bacon, pork sausage).
BEHAVIORAL
Plant Diet
The diet will be a Lacto-Ovo Vegetarian Diet following the Dietary Guidelines for Americans with no more than 21 oz per week of animal protein (e.g., eggs, cheese).
Primary outcome measures
Change in Macrovascular Function
Time frame: From the beginning of the diet period to the end of the diet period at 4 weeks.
Macrovascular function will be measured by endothelial function. Investigators will use brachial artery flow mediated dilation (FMD) using ultrasound. Ultrasound images will be captured (Cardiovascular Suit 4, QUIPU, Pisa, Italy) at three time points 1) end-diastole for each cardiac cycle at baseline (\~30 s), 2) during occlusion (\~5 min), and 3) after occlusion (\~5 min). The shear rate will be calculated for each cardiac cycle as 8 × mean blood velocity/ diameter, and the shear rate area under the curve from cuff release to peak diameter will be quantified as an index of the stimulus for FMD. The FMD values will be expressed as relative (%) changes from baseline to peak diameter and FMD/SRAUC will be corrected for shear rate (FMD/shear rate \[SR\] area under the curve \[AUC\]) in order to account for shear stress inter-individual variability.
Change in Microvascular Function
Time frame: From the beginning of the diet period to the end of the diet period at 4 weeks.
Microvascular blood flow will be assessed by near-infrared spectroscopy for oxygenated hemoglobin/myoglobin (O2Hb/O2Mb), deoxygenated hemoglobin/myoglobin (HHb/HMb), total hemoglobin/myoglobin (tHb/tMb), and tissue oxygen saturation (StO2, %)
Change in Blood Lipids
Time frame: From the beginning of the diet period to the end of the diet period at 4 weeks.
A blood lipid panel (total cholesterol, triglycerides, LDL, and HDL) will be performed at each outcome visit.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Are between 40 and 55 years of age
- Have a BMI (a number calculated from participant height and weight) between 28 and45 kg/m2
- Are experiencing irregular menstrual cycles but have not gone longer than 12 consecutive months without a period
- Are experiencing severe vasomotor (menopause) symptoms
- Are doing less than 3 hours per week of structured exercise
- Have systolic blood pressure between 120 and 140 mmHg and/or diastolic blood pressure between 80 and 90 mmHg
- Have "sugary" hemoglobin called hemoglobin A1c less than or equal to 6.5%
- Are willing and able to refrain from using oral mouth wash for the duration of the study because the alcohol in mouth wash inhibits nitrate synthesis
- Are willing and able to comply with both the study diets
- Are willing to collect blood for future research
- Can read, speak, and understand English
Exclusion criteria
- Hysterectomy (partial or full) or oophorectomy
- Using hormone replacement therapy use and/or hormonal contraception use 6 months prior to study start
- Has systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥ 90 mmHg)
- Triglycerides ≥350 mg/dL, low-density lipoprotein cholesterol (LDL-C) ≥190 mg/dL, and/or taking a lipid-lowering medication -Diagnosed cardiovascular disease, diabetes (type 1 or 2), or endocrine- related disease (e.g. thyroid, PCOS), unstable gastrointestinal disease, kidney, liver, and/or pancreatic disease
- Diagnosed cancer (except skin cancer) in the last 5 years
- Taking \>1 blood pressure medication and/or taking 1 blood pressure medication for \<3 months
- Taking phosphodiesterase-5 inhibitors, anti-coagulants, corticosteroids, metformin, or insulin.
- Weight change ≥6.6 pounds in the past 3 months, actively trying to lose weight, or unwilling to remain weight stable throughout the study
- Current smoking or vaping, Binge and/or heavy drinker
- Food allergies or other reasons preventing consumption of study foods with both study diets
Where
- Baton Rouge, Louisiana
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Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Nov 28, 2025 · Source of record for eligibility and locations