Comparing the effects of a vegan diet to an omnivorous diet before knee surgery

The Effect of a 2-week Preoperative Vegan Diet Versus Omnivorous Diet on the Protein Turnover in the Osteoarthritic Knee

This study is testing whether a vegan diet for two weeks before knee surgery can help older adults with knee osteoarthritis build protein in their muscles and tissues better than a regular diet with meat.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 40 (estimated)
• Ages: 60 Years to 80 Years
• Sex: All
• Sponsor: Wageningen University (Academic / other)
• Drugs / interventions: chemotherapy
• Locations: 2 sites (Arnhem and 1 other locations)
• Trial ID: NCT06130956 on ClinicalTrials.gov

What this trial studies

This study investigates the impact of a 2-week preoperative vegan diet versus an omnivorous diet on protein synthesis rates in various musculoskeletal tissues in older adults with knee osteoarthritis who are scheduled for total knee arthroplasty. The primary objective is to assess how these dietary approaches influence protein turnover in tissues such as Hoffa's fat pad, synovium, tendon, bone, ligaments, menisci, and cartilage. The study aims to provide insights into whether a vegan diet can enhance protein synthesis in these tissues compared to a traditional omnivorous diet.

Who should consider this trial

Good fit: Ideal candidates are older adults aged 60 to 80 years with a BMI between 20-32, scheduled for total knee arthroplasty.

Not a fit: Patients who have followed a vegetarian or vegan diet in the past six months or have certain chronic conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide evidence that a vegan diet may improve recovery outcomes for patients undergoing knee surgery.

How similar studies have performed: While studies on single plant-based foods exist, this approach of a comprehensive vegan diet in older adults is relatively novel and has not been extensively tested.

Eligibility criteria

Inclusion Criteria:

* Written informed consent;
* Patients scheduled for total knee arthroplasty;
* BMI between 20-32 kg/m2;
* Aged 60 - 80 years;
* Mentally competent, as judged by the treating physician;

Exclusion Criteria:

* Following a vegetarian or vegan diet or a diet that affects protein intake during the six months prior to the study;
* Participating in a structured progressive exercise training program in the past three months;
* Lost more than 4 kg body weight during three months prior to the study;
* Chronic use of medications that affect protein metabolism (i.e. systemic corticosteroids, or prescription strength acne medications);
* Being diagnosed with one of the following: diabetes mellitus, rheumatoid arthritis, peripheral artery disease Fontaine III or IV, COPD GOLD III or IV, neoadjuvant chemotherapy or radiotherapy, phenylketonuria, collagen disorders (e.g. Marfan and Ehler-Danlos);
* Alcohol abuse;
* Surgical intervention to the knee in the past four weeks;
* Total parenteral nutrition at day of surgery;
* Glomerular filtration rate (GFR) \<20 mL/min/1.73 m2;
* Allergic or intolerant to any product included in the diets;
* Osteoarthritis of the knee secondary to septic arthritis, osteonecrosis, fracture, osteochondritis dissecans, or malignant processes;
* Any other medical condition that may interfere with the safety of the participants or the outcome parameters, in the investigators judgement;
* Not willing to stop nutritional supplements, with the exception of vitamin D and supplements on medical advice.
* Investigator's uncertainty about the willingness or ability of the participant to comply with the protocol instructions;
* Participation in other studies that may have an impact on the outcomes during the three months before the start of the current study.

Where this trial is running

Arnhem and 1 other locations

• Rijnstate Hospital — Arnhem, Netherlands (Recruiting)
• Hospital Gelderse Vallei — Ede, Netherlands (Recruiting)

Study contacts

• Principal investigator: Lisette de Groot, PhD — Wageningen University
• Study coordinator: Inge Groenendijk, PhD

Conditions Osteo Arthritis Knee; Protein Synthesis