The Effect of a 12-week Self-composed Vegan Diet With or Without Concurrent Resistance Exercise on Thigh Muscle Volume in Older Adults

Not Applicable

Completed

• Conditions: Sarcopenia; Osteoporosis; Gut Health; Cardiovascular Health; Vegan Diet
• Interventions: Other: Omnivorous diet; Other: Vegan diet; Other: Resistance exercise

• Registration Number: NCT05809466
• Lead Sponsor: Wageningen University

Brief Summary

Consumers are increasingly encouraged to consume more plant-based foods and lower their consumption of foods from animal origin. This shift is driven by environmental and health factors. However, the consequences of such a transition on muscle mass still remains to be explored. This is of particular importance in the older population, where the age-related reduction in muscle mass and strength is highly prevalent. Adequate dietary intake, specifically protein intake, is a well-known strategy in promoting muscle mass in older adults. Plant-based foods are currently considered to be inferior to animal-based foods in their protein quality, and are therefore considered to be suboptimal for the maintenance of muscle mass at an older age. On the other hand, combining plant-based foods may improve the protein quality and thereby the anabolic properties of a vegan meal. Evidence regarding the anabolic properties of vegan diets in older adults is scarce. As such, the current study aims to assess 1) the effects of a 12-week self-composed vegan diet in comparison to an omnivorous diet on thigh muscle volume (TMV) in community-dwelling older adults and 2) the effect of a 12-week self-composed vegan diet combined with twice-weekly resistance exercise (RE) on TMV in comparison to a self-composed vegan diet without resistance exercise in community-dwelling older adults.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2023-03-14
• Study First Submitted QC: 2023-03-29
• Study Start: 2023-04-04
• Study First Posted: 2023-04-12
• Primary Completion: 2024-09-26
• Study Completion: 2024-09-26
• Status Verified: 2024-11
• Last Update Submitted: 2025-03-25
• Last Update Posted: 2025-04-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 72

Inclusion Criteria

• Aged ≥65 years old;
• Community-dwelling;
• BMI 23-32 kg/m2;
• Habitual diet contains animal-based food products (i.e. dairy, meat and/or fish) at least 5 days per week;

Exclusion Criteria

• Following a self-reported entirely vegetarian or vegan diet during the six months prior to the study;

• Following a prescribed high (≥1.2 g/kg/d) or low protein diet (<0.8 g/kg/d), and/or or taking protein supplements on medical advice, during the month prior to the study;

• Participating in a structured progressive resistance exercise training program the during three months prior to the study;

• ≥4 kg of body weight loss during three months before the start of the study;

• Being diagnosed with one of the following: diabetes mellitus; renal disease; neurological or neuromuscular disorders; serious cardiovascular diseases; cancer (with the exception of the following types of skin cancer: basal cell carcinoma, squamous cell carcinoma); (very) severe chronic obstructive lung disease (COPD; GOLD stage III or IV); bowel disease.

• Chronic use of medication that affects muscle function as assessed by the research physician;

• The use of anticoagulants incompatible for muscle biopsies as assessed by the research physician: acenocoumarol (sintrom); phenprocoumon (marcoumar); dabigatran (pradaxa); apixaban (eliquis); rivaroxaban (xarelto); clopidogrel (plavix); edoxaban (lixiana); combination of acetylsalicylic acid or carbasalate calcium (ascal) with dipyridamole;

• Having a contra-indication to MRI scanning (including, but not limited to):

  • Pacemakers and defibrillators
  • Infraorbital or intraocular metallic fragments
  • Ferromagnetic implants
  • Claustrophobia

• Having a hip prosthesis

• Not willing to stop nutritional supplements, with the exception of supplements on medical advice, and vitamin D;

• Not willing or afraid to give blood, undergo a muscle biopsy or have an MRI scan during the study;

• Unwilling to eat a self-composed vegan diet or an omnivorous diet with daily consumption of animal-based food sources for 3 months;

• Unwilling to participate in RE twice a week for 3 months;

• Currently a research participant in another trial or participated in a clinical trial during one month before the start of the measurement period;

• Not being able to understand Dutch;

• Not having a general physician;

• Working, or having a direct family member that work at the Division of Human Nutrition at Wageningen University during the study.

• Unwilling to be informed about incidental findings of pathology and approving of reporting this to their general physician.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Omnivorous group	Omnivorous diet	-
Vegan group	Vegan diet	-
Vegan group with resistance exercise	Vegan diet	-
Vegan group with resistance exercise	Resistance exercise	-

Primary Outcome Measures

Name	Time	Method
Change in thigh muscle volume	12 weeks	Thigh muscle volume of both legs will be assessed using magnetic resonance imaging before and after the 3-month intervention

Secondary Outcome Measures

Name	Time	Method
Change in fasting blood pressure	Change after 6 and 12 weeks	Fasting systolic and diastolic blood pressure
Untargeted gut metabolomics	Change after 12 weeks	Untargeted gut metabolomics will be performed on fasting plasma samples
Change in fasting plasma high-sensitive C-reactive protein (hs-CRP)	Change after 6 and 12 weeks	Fasting plasma hs-CRP
Change in bone mineral density	Change after 12 weeks	Measured using a Dual X-Ray Absorptiometry dual femur scan
Change in haemoglobin levels	Change after 12 weeks	Fasting plasma haemoglobin levels
Change in vitamin B12 status	Change after 12 weeks	Fasting plasma methylmalonic acid levels
Change in ferritin levels	Change after 12 weeks	Fasting plasma ferritin levels
Change in plasma insulin growth factor 1 levels	Change after 6 and 12 weeks	Fasting serum insulin-like growth factor 1 (IGF-1)
Change in metabolic profile	Change after 6 and 12 weeks	Fasting plasma levels of multiple metabolites
Change in fasting bone turnover markers	Change after 6 and 12 weeks	Serum procollagen type I N-terminal propeptide (P1NP) will be measured for bone formation and C-terminal telopeptide of type I collagen (CTX) for bone resorption.
Branch-chained amino acids	Change after 12 weeks	Branch-chained amino acids will be assessed using targeted metabolomics on plasma samples
Body composition	Change after 12 weeks	Other body composition indices will also be measured using magnetic resonance imaging before and after the intervention. These indices include: liver fat fraction, thigh muscle fat infiltration, abdominal subcutaneous adipose tissue, visceral fat tissue.
Change in muscle strength	Change after 12 weeks	Maximal isometric knee extension and flexion strength of both legs will be measured using Biodex.
Muscle fractional synthesis rates	10 days	Muscle fractional synthesis rates, expressed as daily fractional synthesis rates (FSR, %/day), will be assessed using a deuterium oxide protocol. Daily FSR will be calculated using the 2\^H-alanine enrichment in plasma and the mixed muscle-bound 2\^H-alanine enrichment.
Change in plasma parathyroid hormone (PTH) levels	Change after 6 and 12 weeks	Fasting plasma PTH
Change in fasting plasma insulin levels	Change after 6 and 12 weeks	Fasting plasma insulin
Change in vitamin D status	Change after 12 weeks	Fasting serum vitamin D levels
Change in gastro-intestinal symptoms	Change after 12 weeks	Self-reported gastro-intestinal symptoms using the gastro-intestinal symptom rating scale. The questionnaire includes 15 questions covering 5 common symptom clusters on a 7-point likert scale ranging from no symptoms (minimum) to severe symptoms (maximum). A higher score indicates worse symptoms.
Tryptophan	Change after 12 weeks	Tryptophan will be assessed using targeted metabolomics on plasma samples
Oxidized amino acids	Change after 12 weeks	Oxidized amino acids will be assessed using targeted metabolomics on plasma samples
Tyrosine	Change after 12 weeks	Tyrosine will be assessed using targeted metabolomics on plasma samples
Gut metagenomics	Change after 12 weeks	Microbial DNA will be isolated from the feces samples. The taxonomy and function of specific genes will be assessed via metagenomic sequencing on the microbial DNA.

Trial Locations

Locations (1)

Wageningen University and Research; 🇳🇱 Wageningen, Gelderland, Netherlands