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Clinical Trial Details — Status: Enrolling by invitation

Administrative data

NCT number NCT05740462
Other study ID # The Harvest Study
Secondary ID
Status Enrolling by invitation
Phase N/A
First received
Last updated
Start date May 4, 2023
Est. completion date September 1, 2025

Study information

Verified date February 2023
Source Quadram Institute Bioscience
Contact n/a
Is FDA regulated No
Health authority
Study type Interventional

Clinical Trial Summary

Veganism and vegetarianism have clear benefits where they have a lower risk of many health issues. However, they also have a higher risk of nutrients and vitamin deficiency such as iron and vitamin B12. Iron can be found in plant-based food but in varying quantities, whereas vitamin B12 is mainly found in red meat, thus vegans and vegetarians can only take this vitamin in supplements such as tablets. In this study, the investigators are testing two interventions, the consumption of recipes with a certain iron amount to increase iron levels, and the consumption of vitamin B12 biofortified plants to increase serum B12 levels in vegan and vegetarian participants.


Description:

Iron is present in plant and animal-derived foods but the fractional absorption of iron from plant foods (that is the percent of iron absorbed from a consumed quantity) is often low (approx 10%) compared to iron from animal sources 25%-30%. It is therefore more challenging for vegans and vegetarians to achieve the Reference Nutrient Intake (RNI) for iron (8.7 mg/day for men over 18 and women over 50, 14.8 mg/day for women aged 18-50), and they are likely to absorb less of that iron and therefore are more likely to become iron depleted. Plants do not synthesise vitamin B12 and unless fortified, plant-derived foods and beverages do not contain any vitamin B12. the RNI for vitamin B12 in the UK is 1.5 µg/day, therefore it is crucial that vegans and vegetarians take B12 supplements if they don't consume B12-fortified foods or find other ways of incorporating this vitamin into their diets. The HARVEST study is a 17-week randomised, controlled, double-blinded, parallel dietary intervention study conducted at the Quadram Institute Clinical Research Facility (QI CRF), Norwich, UK. Investigators are seeking vegan or vegetarian women (18 to 50 years old) to test two interventions, iron-specific recipes and B12 biofortified plants grown in a kitchen garden. There are a total of 4 visits (1 screening visit, 2 2-hours visits and 1 short visit). Investigators will assess blood samples for serum ferritin, serum B12 and other iron and B12 biomarkers. Investigators will ask the participant to complete lifestyle questionnaires regarding their dietary pattern, fatigue level and satisfaction and impression of the study tools.


Recruitment information / eligibility

Status Enrolling by invitation
Enrollment 52
Est. completion date September 1, 2025
Est. primary completion date June 1, 2024
Accepts healthy volunteers Accepts Healthy Volunteers
Gender Female
Age group 18 Years to 50 Years
Eligibility Inclusion Criteria: 1. Women over 18 years with a regular menstruation cycle (>21 and <40 days). 2. Has followed a vegan or vegetarian diet that does not include the consumption of meat or fish for at least 1 year. 3. Willing to remain on their background diet for the duration of the study. 4. Those who are on a routine regimen of iron and/or vitamin B12 supplements must maintain the same doses 3 month prior to the study and during the duration of the study. 5. Non-anaemic, haemoglobin (Hb) concentration =120 g/L. 6. SF >15 µg/L and <40 µg/L [WHO uses the following cut-offs for context: below 15 µg/L indicates iron deficiency, 16-40 µg/L indicates borderline deficiency, and 41 - 150 µg/L is normal]. 7. Body Mass Index (BMI) between 18.5 - 40 kg/m2. 8. Live within 40 miles of the Norwich Research Park. 9. Willing to consume plants grown in the hydroponic unit (e.g., spinach, rocket, mizuna) if they agreed to have a unit. 10. Access to a smartphone or online platform a well as access to the internet. Exclusion Criteria: 1. Those who have known allergies to the hydroponically grown salad greens (spinach, rocket, mizuna). 2. Flexitarian (consumes meat intermittently) vegetarian. 3. Those with menstruation cycle time periods of <21 or >40-days 4. BMI at screening visit < 18.5 kg/m2 (underweight) and > 40 kg/m2 (severely obese). 5. Those diagnosed with or undergoing treatment for anaemia. 6. Currently pregnant, lactating or trying to conceive. 7. High alcohol consumption, consuming more than 2 drinks per day, can elevate the risk for iron overload. 8. Current smoker or has only ceased in the last 6 months. 9. Diagnosed medical conditions that may impact the study outcomes will be considered on an individual basis. 10. Those with an eating disorders, which may impact the study outcome. 11. On, or about to start, a diet programme such as the 5:2 programme (5:2 programme is where an individual would eat normally for five days a week, and fast for two days a week by reducing calorie consumption). 12. Unable to give written or verbal informed consent. 13. Individuals who cannot understand the written instructions/questionnaires. 14. Unwilling to give GP contact details. 15. Participating in another dietary intervention study or has given blood in another research study during the last 3 months. 16. Any person related to or living with any member of the study team. 17. Those who are part of the Line Manager/supervisory structure of the Chief Investigator. 18. Those who have been asked to self-isolate or have been diagnosed with COVID-19 in the last 14 days. However, participants can be rescreened 7 days after the isolation period.

Study Design


Intervention

Behavioral:
Recipes consumption
Participants will eat two recipes a day for 17 weeks
Hydroponic unit
Participants will grow vitamin B12 biofortified plants for 17 weeks and consume (10 grams) of plant material for 11 weeks.

Locations

Country Name City State
United Kingdom Quadram Institute Bioscience Norwich

Sponsors (2)

Lead Sponsor Collaborator
Quadram Institute Bioscience Norfolk and Norwich University Hospitals NHS Foundation Trust

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type Measure Description Time frame Safety issue
Primary Change in serum ferritin after the dietary app intervention Comparison of serum ferritin at baseline and after the intervention Week: 0, 6/7 and 17
Primary Change of serum B12 after the hydroponic unit intervention Comparison of serum B12 at baseline and after the intervention Week: 6/7 and 17
Secondary Change in high sensitivity C-reactive protein (hsCRP) with dietary app (high or standard iron) recipe intervention comparison of hsCRP at baseline and after dietary app intervention Week: 0 to 6/7, 6/7 to 17, and 0 to 17
Secondary Change in full blood count (FBC) with dietary app (high or standard iron) recipe intervention comparison of FBC in venous blood sample at baseline and after dietary app intervention Week: 0 to 6/7, 6/7 to 17, and 0 to 17
Secondary Change in soluble transferrin receptor (sTfR) with dietary app (high or standard iron) recipe intervention comparison of sTfR in venous blood sample at baseline and after dietary app intervention Week: 0 to 6/7, 6/7 to 17, and 0 to 17
Secondary Change in alpha 1 acid glycoprotein (AGP) with dietary app (high or standard iron) recipe intervention comparison of AGP in venous blood sample at baseline and after dietary app intervention Week: 0 and 17
Secondary Change in holo-transcobalamin (Holo-TC) after the hydroponic unit (biofortification) intervention Measurement of holo-TC in venous blood sample at baseline and after the hydroponic unit intervention Week: 0 and 17
Secondary Change in methylmalonic acid (MMA) after the hydroponic unit (biofortification) intervention Measurement of MMA in venous blood sample at baseline and after the hydroponic unit intervention Week: 0 and 17
Secondary Change in total plasma homocysteine (tHcy) after the hydroponic unit (biofortification) intervention Measurement of tHcy in venous blood sample at baseline and after the hydroponic unit intervention Week: 0 and 17
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