None listed
Conditions
Brief summary
The aim of this study is to determine whether regular consumption of cruciferous vegetables (e.g. broccoli, cabbage, cauliflower, kale) results in short-term improvement in measures related to cardiovascular disease risk, including blood pressure, arterial stiffness, glycaemic control, and circulating biomarkers of oxidative stress and inflammation. Twenty-eight participants (50-75 years) with mildly elevated blood pressure (systolic blood pressure 120-160 mmHg) will complete two 2-week interventions in a random order, separated by a 2-week washout period. During each intervention, participants will consume 4 servings/day (300 g) of vegetables as a soup (~500-600 mL/day). The 'active' soup will consist of cruciferous vegetables (broccoli, cabbage, cauliflower, kale) and the ‘control’ soup will consist of other commonly consumed vegetables (potato, sweet potato, carrot, pumpkin). Both soups will be approximately matched for energy, protein, fat, and carbohydrate content. All measurements will be performed at the beginning and end of each intervention period.
Interventions
The two 2-week dietary treatments will correspond to:
1. Cruciferous vegetables (CV): 4 servings (~300 g) of cruciferous vegetables (broccoli, cabbage, cauliflower, and kale) per day consumed as a soup at lunch and dinner (~500-600 mL soup/day); and
2. Starchy vegetables (SV): 4 servings (~300 g) of commonly consumed vegetables (potato, sweet potato, carrot, and pumpkin) per day consumed as a soup at lunch and dinner (~500-600 mL soup/day).
Both treatment soups will be approximately matched fo
The two 2-week dietary treatments will correspond to: 1. Cruciferous vegetables (CV): 4 servings (~300 g) of cruciferous vegetables (broccoli, cabbage, cauliflower, and kale) per day consumed as a soup at lunch and dinner (~500-600 mL soup/day); and 2. Starchy vegetables (SV): 4 servings (~300 g) of commonly consumed vegetables (potato, sweet potato, carrot, and pumpkin) per day consumed as a soup at lunch and dinner (~500-600 mL soup/day). Both treatment soups will be approximately matched for energy, protein, fat, and carbohydrate content. Soups will be prepared at Edith Cowan University, Joondalup Campus, using a standardized recipe and frozen for storage. Participants will be advised to consume their regular breakfast and snacks during the trial and to keep this consistent throughout. During intervention periods, participants will consume standard lunch and dinner meals provided by the study investigators to limit background dietary variation. The lunch and dinner meals provided to participants will be pre-packaged frozen meals available from supermarkets (e.g. McCain Healthy Choices, Lean Cuisine). It is expected that participants will have a background vegetable intake of approximately 1-4 servings per day during the intervention periods. Therefore, the additional 4 servings of vegetables that the soups will provide will shift vegetable intake to at or above the recommended 5-6 servings per day. There will be a 2-week washout period between the two intervention periods. A daily food diary will be used, along with other compliance measures, to monitor adherence throughout the study. Daily food diaries will either be paper-based or app-based (Food Research Diary, Xyris Software, Australia), depending on participant preference. All food data will later be entered into Foodworks (Xyris Software, Australia) for analysis.
Sponsors
Edith Cowan University
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
50 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
We will recruit ambulant community-dwelling men and women aged between 50 and 75 years who have mildly elevated blood pressure (systolic blood pressure 120-160 mmHg, inclusive, and diastolic blood pressure <100 mmHg).
Exclusion criteria
Volunteers will be excluded from participation based on the following criteria: body mass index <18.5 or =40 kg/m2; systolic blood pressure >160 mmHg or <120 mm Hg; diastolic blood pressure >100 mmHg; use of >2 antihypertensive medications or irregular use of nitric oxide donors, organic nitrites and nitrates, and sildenafil and related drugs; diagnosed diabetes or fasting blood glucose >6.5 mmol/L; fasting total cholesterol >8 mmol/L; current or recent (<12 months) smoking; adhesive allergy; regular aspirin use; medication use for thrombosis or anticoagulants (Warfarin); history of cardiovascular or peripheral vascular disease (myocardial infarction, stroke, transient ischaemic attack, amputation due to arterial insufficiency, any form of arterial revascularisation, history of exertional angina or claudication); psychiatric illness or other major illnesses, such as cancer; alcohol intake >100 g per week; current or recent (within previous 6 months) significant weight loss or gain (>6% of body weight) or actively trying to lose weight; pre-menopausal women; inability to attend clinic/office visits; use of antibiotics (within previous 2 months); use of antibacterial mouthwash and not willing to cease for trial duration; reported participation in night shift work during the study period; and inability or unwillingness to follow the study protocol. Volunteers with specific dietary requirements, allergies, or intolerances (e.g. following a low FODMAP diet) that will interfere with their ability to follow the dietary requirements of the study will also be excluded.
Outcome results
None listed