The main aim of the current study is to investigate the effect of a 12 week dietary intervention focusing on increasing vegetable intake on 24h blood pressure. Besides, we want to investigate the effects on:- Plasma concentrations: plasma nitrate…
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
hypertentie
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The main aim of the current study is to investigate the effect of a 12 week
dietary intervention focusing on increasing vegetable intake on 24h blood
pressure.
Secondary outcome
- Plasma concentrations: plasma nitrate and nitrate, plasma cholesterol, HDL,
LDL, triglyceride, troponin I;
- Dietary intake: total macro- and micronutrient intake, vegetable and dietary
nitrate intake;
- Blood pressure and heart rate
- Submaximal aerobic endurance exercise
Background summary
Green leafy vegetables (e.g., spinach, rocket salad/arugula, lettuce) and
beetroot share the common characteristic of high nitrate content. Recently,
there has been an increased interest in the role of dietary nitrate as a
biologically active nitric oxide (NO) donor, due to its proposed effects on
cardiovascular health. Therefore, food based ways of increasing nitrate intake
through the diet appear to form a worthwhile strategy to induce cardio
protective effects. However, there is a lack of knowledge on the effects of a
prolonged nitrate intake via the habitual diet.
Study objective
The main aim of the current study is to investigate the effect of a 12 week
dietary intervention focusing on increasing vegetable intake on 24h blood
pressure. Besides, we want to investigate the effects on:
- Plasma concentrations: plasma nitrate and nitrate, plasma cholesterol, HDL,
LDL, triglyceride, troponin I;
- Dietary intake: total macro- and micronutrient intake, vegetable and dietary
nitrate intake;
- Blood pressure and heart rate
- Submaximal aerobic endurance exercise
Study design
The present study will use a randomized, controlled, parallel study design
Intervention
12 weeks of educational intervention with intense (weekly) personalized
monitoring and feedback focusing on nitrate rich vegetables (intervention
group), dietary nitrate supplementation (supplementation group) or no
intervention (control group).
Study burden and risks
For this study participants will be required to report to the research facility
for a total of two visits (duration ~60 minutes).
Participants follow a nutritional intervention where they are coached weekly
(~60 minutes, every week) to improve their eating behaviour or are instructed
to use a dietary nitrate supplement daily. During the study period,
participants have to fill in a dietary record (three total, ~60 minutes per
recall). Participants are asked to refrain from strenuous physical exercise or
labour for the 24 h preceding the test days. In addition, participants will be
asked to avoid caffeine and alcohol for 12 and 24 h preceding each visit. They
will be asked to refrain from using any antibacterial mouthwash/toothpaste, and
tongue-scraping throughout the course of the study (as this interferes with the
conversion of nitrate to nitrite in the oral cavity). A venepuncture will be
performed for blood sample collection during each test day. Withdrawal of a
venous blood sample is associated with a 5% risk of developing a haemorrhage,
but will fully disappear within 2 weeks and is not associated with any
(functional) limitations. The repeated blood pressure measurements during a
24-h recording are known to cause some discomfort when the cuff is inflated to
a suprasystolic pressure, and requires participants to remain still during the
measurement. This is also the case during the lab-based blood pressure
measurements. The advised daily intake of (nitrate rich) vegetables in the
current study has been administered in multiple intervention studies. No
adverse events were reported, except for mild gastrointestinal distress
(bloating, belching) in a few cases.
Heyendaalseweg 141
Nijmegen 6525 AJ
NL
Heyendaalseweg 141
Nijmegen 6525 AJ
NL
Listed location countries
Age
Inclusion criteria
- Elevated blood pressure or stage 1 hypertension:
Elevated blood pressure. Elevated blood pressure is a systolic pressure ranging from 120 to 129 mm Hg and a diastolic pressure below 80 mm Hg. Elevated blood pressure tends to get worse over time unless steps are taken to control blood pressure.
Stage 1 hypertension. Stage 1 hypertension is a systolic pressure ranging from 130 to 139 mm Hg or a diastolic pressure ranging from 80 to 89 mm Hg.
- Current vegetable intake <200 g/d based on FFQ;
- Registered for the Nijmegen Four Days Marches 2019;
- 18.5 < BMI * 35.0 kg/m2;
- Able to understand and perform the study procedures.
Exclusion criteria
- Use of medication (with known vasoactive properties);
- Currently smoking
- Currently supplementing diet with nitrate.
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
In other registers
| Register | ID |
|---|---|
| CCMO | NL68764.072.19 |
| Other | Onderzoek is aangemeld, ik wacht op een NCT nummer |
| OMON | NL-OMON21682 |