Here is the design of a clinical trial:

Official Title: Effects of Long-term Consumption of Two Plant-based Dietary Supplements on Cardiovascular Health and Low-grade Inflammation in the Elderly

Included conditions:
- Aging
- Cardiovascular Diseases
- Overweight or Obesity

Study Armgroups:
- {'label': 'Control group', 'type': 'NO_INTERVENTION', 'description': 'Continue habitual diet and lifestyle.'}
- {'label': 'Fruit, Vegetable and Berry (FVB) group', 'type': 'EXPERIMENTAL', 'description': 'Participants have to ingest an encapsulated juice powder concentrate, otherwise continue their habitual diet and lifestyle.', 'interventionNames': ['Dietary Supplement: Juice Plus+ Fruit, Vegetable and Berry blends']}
- {'label': 'Omega group', 'type': 'EXPERIMENTAL', 'description': 'Participants have to ingest a plant-based fatty acid supplement, otherwise continue their habitual diet and lifestyle.', 'interventionNames': ['Dietary Supplement: Juice Plus+ Omega blend']}
- {'label': 'Fruit, Vegetable, Berry and Omega (FVBO) group', 'type': 'EXPERIMENTAL', 'description': 'Participants have to ingest an encapsulated juice powder concentrate along with a plant-based fatty acid supplement, otherwise continue their habitual diet and lifestyle.', 'interventionNames': ['Dietary Supplement: Juice Plus+ Fruit, Vegetable and Berry blends', 'Dietary Supplement: Juice Plus+ Omega blend']}

Interventions:
- {'type': 'DIETARY_SUPPLEMENT', 'name': 'Juice Plus+ Fruit, Vegetable and Berry blends', 'description': 'Encapsulated juice powder concentrate derived from 36 dried fruits, vegetables and berries.', 'armGroupLabels': ['Fruit, Vegetable and Berry (FVB) group', 'Fruit, Vegetable, Berry and Omega (FVBO) group']}
- {'type': 'DIETARY_SUPPLEMENT', 'name': 'Juice Plus+ Omega blend', 'description': 'Encapsulated plant-based fatty acid supplement.', 'armGroupLabels': ['Fruit, Vegetable, Berry and Omega (FVBO) group', 'Omega group']}

Primary Outcomes:
- {'measure': 'Lipid profile markers', 'description': 'Total cholesterol, HDL, LDL, ApoA1, triglycerides, Omega-3-Index', 'timeFrame': '12 months'}
- {'measure': 'Hemostasis markers', 'description': 'Platelet aggregation, thrombelastometry, coagulation (Quick, PT, PTT)', 'timeFrame': '12 months'}
- {'measure': 'Oxidative stress markers', 'description': 'oxLDL, MDA, carbonyl proteins, (CP), redox state of albumin, homocysteine', 'timeFrame': '12 months'}
- {'measure': 'Glucose metabolism', 'description': 'Glucose, insulin, HOMA-IR, HbA1c', 'timeFrame': '12 months'}
- {'measure': 'Concentration changes in cytokines/ cytokine receptors', 'description': 'TNF-α, sTNFR1 and sTNFR2, CCL5 = RANTES, IL-1β, hsCRP, CCL2 = MCP-1, Osteoprotegerin (OPG), IL-5, IL-8', 'timeFrame': '12 months'}

Please estimate the sample size based on the assumption: 
two-tailed t-test, 5% significance level (two-sided), 80% power, 30% dropout rate over 24 months
Sample size
          The sample size calculation was performed according to omega-3 index changes as a key biomarker of cardiovascular health and TNF-Î± changes as a key biomarker of low-grade inflammation, following supplementation. Assuming a two-tailed t-test using 5% significance level (two-sided), a sample size of 18 and 19 subjects per group was determined to have 80% power to detect a 30% increase on omega-3 index [32] and a minimum decrease of 0.4 ng/L on TNF-Î± [43], respectively. Allowing for a dropout rate of 30% over 24 months, we aim to recruit 112 participants in total (nâ=â28 control group; nâ=â28 FVB group; nâ=â28 Omega group; nâ=â28 FVBO group).