Tomato Supplementation and Cardiovascular Health
Condition: Healthy
Study type: Interventional

Summary: 
      This clinical trial aims to test the effects of consuming two types of tomato (one ordinary
      cherry red tomato containing lycopene, and the other a yellow cherry tomato low in lycopene),
      on cardiovascular risk factors including endothelial function as the primary outcome, and
      blood lipids, inflammatory factors and blood pressure.

      In a crossover design, participants of this study will randomly consume 300g of raw cherry
      (red and yellow) tomatoes per day for four weeks, with a control period consuming no tomato
      products. Before and after each intervention, the cardiovascular outcomes mentioned above
      will be measured in the clinic.
    

Detailed description: 
      This study will have a randomised and crossover design of 2 interventions supplementing
      300g/day of two different varieties of tomato; each of these interventions will last for 4
      weeks, with a control period (no tomato consumption) of 4 weeks between these. The total
      study period will be 12 weeks. The target sample size for this study is 30 male participants.
      This study visit involve 4 study visits over a 12-week period plus a screening visit before
      the intervention.

      In this study, the interventions will require participants to consume two different varieties
      of fresh tomatoes in random order. Participants will be given all the tomato to be consumed
      during the study, and will be instructed not to consume additional tomato sources. The amount
      of tomato to be consumed will be delivered every week. Participants will consume the tomatoes
      anytime as snack or with meal. In order to control for other dietary factors, participants
      will also be asked to record food diary throughout the first study period (4 weeks) and will
      be recommended to repeat their own dietary pattern for the control period and second study
      period to match up the food and nutrition intake throughout the whole study. They should not
      alter their usual diet and exercise patterns when completing the food diary or study. Before
      and after each 4 weeks intervention or control period, participant will attend the study
      visit for measurements.

      Baseline measurements will be taken at the start of the first study period. All measurements
      will be measured at fasted state on before and after 4-week study period. Anthropometric
      measurements including height and weight, a total of 72ml venous blood samples (18ml each
      measurement) will be collected by researcher. Spot urine and saliva samples will be collected
      into a flask provided by participants themselves. Plasma and urine analyses will not commence
      until the full intervention study is complete, and all samples from each subject are analysed
      within one batch to reduce inter-batch variation. Trained researchers will obtain blood
      sample in this study.

      Before the start of the trial, 4 volunteers will be recruited to consume 1 week of 300g red
      cherry tomato per day for 7 days in order to establish expected serum levels of lycopene
      after tomato supplementation. The aim of this is to develop cut-off serum levels to establish
      compliance with interventions. Six ml of fasting blood will be taken at baseline and after
      the 1 week consumption of red cherry tomato.
    

Intervention name(s): Red cherry tomato; Yellow cherry tomato
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): 300 grams of cherry tomatoes per day for four weeks (each); 300 grams of cherry tomatoes per day for four weeks (each)
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Prevention