The effect of food change between traditional Tanzanian and western-type foods on inflammation and metabolism
| ISRCTN | ISRCTN15619939 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN15619939 |
| Secondary identifying numbers | DIET-study version 1.1 |
- Submission date
- 01/03/2021
- Registration date
- 26/03/2021
- Last edited
- 04/04/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Nutritional, Metabolic, Endocrine
Plain English summary of protocol
Background and study aims
The current wave of urbanization and dietary transition that takes place in many African regions has profound effects on the function of the immune system. This coincides with changes in disease epidemiology with a sharp increase in non-communicable diseases (NCDs), along with the ongoing high burden of infectious diseases. Important gaps remain in our insight into the mechanisms underlying this epidemiologic transition. Recent studies, including data in healthy Tanzanian individuals, suggest that a switch from unprocessed or locally processed traditional low-calorie, high-fiber diet to a high-caloric, high-fat more industrialized processed food ‘western-type’ diet increases inflammation. Therefore, this study aims to assess the inflammatory and metabolic effects and changes in gut microbial profiles of a 2-week food change.
Who can participate?
Healthy Tanzanian male individuals aged 20-40 and living in a rural or urban area in the Moshi district in the Kilimanjaro region.
What does the study involve?
Recruited rural living individuals will be fed a high-fat, high simple-sugar, high-calorie intake and low-fiber more industrialized processed food ‘western-type’ diet and urban living individuals a low-fat, low simple sugar, high-fiber unprocessed or locally processed traditionally rural-type diet. Participants will be provided with meals three times daily for 2 weeks under the cost of the project. Food will be prepared by an experienced cook using stringent hygienic measures and served at the place of preparation.
What are the possible benefits and risks of participating?
Risks associated with short dietary intervention are minimal. This may include mild gastrointestinal symptoms that are easy to resolve in a few days, such as diarrhea, bloating or constipation, due to sudden dietary changes. Regarding sample collection, procedures used have only minimal risk such as local hematoma related to blood sampling. Volunteers will also have no direct benefit from the intervention. However, volunteers who consent to participate will receive free health check-ups for HIV, malaria, blood sugar and blood pressure. The cost of transport to the KCRI research center situated in Moshi municipal in the Kilimanjaro region, Tanzania for blood and stool sampling will be reimbursed to the participants. The only burden overseen for participation in this study is that participants will be required to visit the cooking facility to take meals three times a day for 2 weeks and to visit the KCRI Clinical Trial Unit for sampling at the beginning and the end of the intervention. However, the cooking facility for the rural participants will be placed close to the sampling area so that participants can access it easily.
Where is the study run from?
Kilimanjaro Clinical Research Institute (Tanzania)
When is the study starting and how long is it expected to run for?
September 2020 to August 2021
Who is funding the study?
The Joint Programming Initiative a Healthy Diet for a Healthy Life (JPI HDHL)
Who is the main contact?
Godfrey Temba
gtemba@kcmuco.ac.tz
Contact information
Scientific
Internal Medicine
Radboudumc
PO Box 9101
Nijmegen
6500HB
Netherlands
 ORCID ID |
0000-0001-6056-157X |
|---|---|
| Phone | +31 (0)24 361 09 29 |
| quirijn.demast@radboudumc.nl |
Public
Kilimanjaro Christian Medical University College (KCMUCo)
Moshi
PO Box 2240
Tanzania
| ORCID ID |
0000-0002-1093-3037 |
|---|---|
| Phone | +255 (0)272753616 |
| gtemba@kcmuco.ac.tz |
Public
Kilimanjaro Clinical Research Institute (KCRI)
Moshi
PO Box 2236
Tanzania
| ORCID ID |
0000-0001-6120-3985 |
|---|---|
| Phone | +255 (0)27 2754201 |
| v.kullaya@kcri.ac.tz |
Study information
| Study design | Single-center prospective intervention study, self-controlled randomized design |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Self-controlled randomized trial |
| Study setting(s) | Community |
| Study type | Other |
| Participant information sheet | Not available in web format, please use contact details to request a participant information sheet |
| Scientific title | The inflammatory and metabolic effects of a 2-week food change between traditional Tanzanian and western-type foods in healthy Tanzanian male individuals |
| Study acronym | DIET |
| Study objectives | The hypothesis underlying the current study proposal is that the change from unprocessed or locally processed traditional Tanzanian food to an industrially processed, energy-dense, high-fat, high-calorie food, increases inflammation and leads to significant modulation in food-derived and endogenous plasma metabolites, lipids, and gut microbiome changes. |
| Ethics approval(s) | 1. Approved 30/09/2020, Kilimanjaro Christian Medical College Research Ethics and Review Committee (CRERC) (PO Box 2240, Moshi, Tanzania; +255 (0)2753616; beatrice.temba@kcmuco.ac.tz), ref: 2483 2. Approved 03/12/2020, National Institute for Medical Research (NIMR), Tanzania (3 Barack Obama Drive, PO Box 9653, 11101 Dar es Salaam, Tanzania; +255 (0)22 2121400; hq@nimr.or.tz, info@nimr.or.tz), ref: NIMR/HQ/R.8a/Vol. IX 3570 |
| Health condition(s) or problem(s) studied | Inflammatory and metabolic effect of food change between traditional and western-type foods in healthy male individuals |
| Intervention | This dietary intervention will focus on the effect of food change between traditional Tanzanian and western-type foods on inflammatory, metabolic changes and changes in the gut microbiome composition. A total of 76 healthy male individuals aged 20-40 years living in either urban area (n=48) or a rural area in Moshi districts (n=28) will be enrolled. In part one: Participants consuming a traditional high-fiber, low-simple sugar, low-fat traditional Tanzanian type diet (rural area) or a low-fiber, high-simple sugar, high-fat western-type diet (urban area) will be selected using a dietary recall history of the previous week. First, dietary habits in the home environment will be studied for 1 week with participants taking their usual diet. Blood and stool samples will be taken after this week. Per group (rural/urban), participants will be randomized for the dietary intervention for 2 weeks (n=23 per group) or remain on their usual diet (n=5 per group). In part two: Banana brew (mbege) is commonly consumed in rural areas. Mbege is made from fermented banana to which millet is added. Mbege contains yeast (Saccharomyces cerevisiae) and is a rich source of fibers, flavonoids (millet), and the disaccharide trehalose. Both flavonoids and trehalose exhibit anti-inflammatory properties. To test the immune-modulatory effect of consuming banana brew, 20 volunteers from the urban area who consume alcohol, but not banana beer will be randomized for a banana beer intervention for 1 week. Participants will receive 1 l of a local brew ‘Mbege’ daily while consuming their usual diet. The effect of other factors will be controlled by taking measurements from the same participants before and after the intervention. Blood and stool samples will be taken before and after the intervention period of 1 week. |
| Intervention type | Behavioural |
| Primary outcome measure | Current primary outcome measures as of 29/03/2021: 1. Circulating inflammation-related human protein biomarkers measured using enzyme-linked immunosorbent assay (ELISA) or comparable techniques at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 2. The capacity of the circulating immune cells to produce inflammatory cytokines in ex vivo whole blood stimulation to different stimuli, measured using ELISA on the culture supernatant at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 3. Blood transcriptome measured using RNAseq technology with NovaSeq™ Sequencing System at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 4. Plasma metabolome assessed using high-throughput mass spectrometry (untargeted metabolomics) at baseline (day 0), post intervention (day 14) and optionally at day 30 post intervention (day 44) 5. Coagulation parameters (thrombin and plasmin generation) measured using modified calibrated automated thrombography (MidiCAT; Synapse Research Institute, Maastricht, the Netherlands) at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 6. Gut microbiome composition measured using metagenomic sequencing of stool samples collected at baseline (day 0), post intervention (day 14) and optionally at 30 days post intervention (day 44) Previous primary outcome measures: Measured at baseline and after 2 weeks of the dietary intervention: 1. Circulating inflammation-related human protein biomarkers measured using enzyme-linked immunosorbent assay (ELISA) or comparable techniques at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 2. The capacity of the circulating immune cells to produce inflammatory cytokines in ex vivo whole blood stimulation to different stimuli, measured using ELISA on the culture supernatant at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 3. Blood transcriptome measured using RNAseq technology with NovaSeq™ Sequencing System at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 4. Plasma metabolome assessed using high-throughput mass spectrometry (untargeted metabolomics) at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 5. Plasma lipids (lipidome) measured using mass spectrometry analysis (LC-MS) at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) 6. Coagulation parameters (thrombin and plasmin generation) measured using modified calibrated automated thrombography (MidiCAT; Synapse Research Institute, Maastricht, the Netherlands) at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) |
| Secondary outcome measures | Current secondary outcome measure as of 29/03/2021: Plasma lipids (lipidome) measured using mass spectrometry analysis (LC-MS) at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44) Previous secondary outcome measure: Gut microbiome composition measured using metagenomic sequencing of stool samples collected at baseline (day 0), post intervention (day 14) and 30 days post intervention (day 44). |
| Overall study start date | 30/09/2020 |
| Completion date | 09/08/2021 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Lower age limit | 20 Years |
| Upper age limit | 40 Years |
| Sex | Male |
| Target number of participants | 76 |
| Total final enrolment | 76 |
| Key inclusion criteria | 1. Tanzanian healthy male individuals aged 20-40 years and BMI 18-25 kg/m² 2. Living either in rural or in urban areas in the Moshi district for more than a month before participation and consuming either a traditional Tanzanian or a western-type diet 3. Use alcohol, either local brew ‘Mbege’ or commercially available beer 4. Can stay in the study area throughout the intervention period Justification: Age, gender, and BMI are known to influence immune responses including inflammation, and they also affect the composition of gut microbiota. Elderly individuals have declined immune function, a phenomenon referred to as immunosenescence, while higher BMI is associated with increased inflammation. On the other hand, females have varying hormonal levels linked to the menstrual cycle and the use of contraceptives. The choice of age categories, BMI range, and sex are done to limit the well know confounding effects of these factors on inflammation and on gut microbiota composition among individuals. |
| Key exclusion criteria | 1. HIV seropositive 2. Malaria seropositive - updated 29/03/2021: positive malaria rapid diagnostic test 3. Blood pressure outside the defined range (≤60 mmHg diastolic or ≥140 mmHg systolic) 4. Fasting blood sugar (>6.0 mmol/l) 5. BMI outside the defined range (18-25 kg/m²) 6. Food allergies 7. Acute (febrile) illness in the previous month 8. Use of any medication as well as the use of antibiotics in the past three months or vaccination 9. hospital admission in the past year 10. A known chronic condition such as active malignancy, liver or kidney disease, tuberculosis infection, chronic hepatitis B or C infection 11. History of hypertension, diabetes, cardiovascular diseases 12. Failure to consent 13. Female sex 14. None alcohol users or reported alcoholism 15. Participation in another clinical trial at the same time or within the last 30 days |
| Date of first enrolment | 12/04/2021 |
| Date of final enrolment | 05/07/2021 |
Locations
Countries of recruitment
- Tanzania
Study participating centre
PO Box 2236
Tanzania
Sponsor information
Hospital/treatment centre
Geert Grooteplein-Zuid 10
Nijmegen
6525GA
Netherlands
| Phone | +31 (0)243616980 |
|---|---|
| quirijn.demast@radboudumc.nl | |
| Website | https://radboudumc.nl |
"ROR" |
https://ror.org/05wg1m734 |
Research organisation
Sokoine Road
Moshi
PO Box 2236
Tanzania
| Phone | +1 (0)255 27 2754201 |
|---|---|
| kcriadmin@kcri.ac.tz | |
| Website | http://www.kcri.ac.tz/ |
Funders
Funder type
Research organisation
Private sector organisation / Associations and societies (private and public)
- Alternative name(s)
- JPI A Healthy Diet for a Healthy Life, Healthy Diet for a Healthy Life, JPI HDHL
- Location
- Netherlands
Results and Publications
| Intention to publish date | 01/03/2025 |
|---|---|
| Individual participant data (IPD) Intention to share | No |
| IPD sharing plan summary | Stored in repository |
| Publication and dissemination plan | The results will be disseminated in the form of written reports. Significant results will be communicated to the research community via publications in scientific journals and through social media. The permission to submit manuscripts for publication will be sought from NIMR as per regulations and the published articles will also be shared with NIMR. The presentation of the findings will be organized for the following groups; first, to the CRERC and to the clinicians at KCMC to raise awareness on the impact of urbanization particularly dietary change on the epidemic of non-communicable diseases in our setting. Second, to the public to create awareness and provide education. The results will also be presented in a different national and international conference organized on non-communicable diseases in which the results of this project will be shared with the NCDs stakeholders and the community at large. Additional documents are not available. The researchers have no intention to publish the study protocol. |
| IPD sharing plan | Sequence data will be deposited at the European Genome–phenome Archive, which is hosted by the EBI and the CRG, and the accession number will be made available after publication. Metabolomics data will be deposited to the EMBL-EBI MetaboLights database the study identifier will be available after publication. Other datasets such as metadata circulating inflammatory proteins and ex vivo cytokines will be stored in the Data Archiving and Networked Services (DANS) repository (https://dans.knaw.nl). |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Protocol file | 01/05/2020 | 10/10/2022 | No | No | |
| Results article | 03/04/2025 | 04/04/2025 | Yes | No |
Additional files
Editorial Notes
04/04/2025: Publication reference added.
18/09/2024: The intention to publish date was changed from 01/09/2024 to 01/03/2025.
01/03/2024: The intention to publish date was changed from 01/09/2023 to 01/09/2024.
10/10/2022: The following changes have been made:
1. Protocol file uploaded.
2. The intention to publish date has been changed from 29/09/2022 to 01/09/2023.
08/07/2021: The following changes have been made:
1. The recruitment end date has been changed from 30/07/2021 to 05/07/2021.
2. The overall trial end date has been changed from 29/09/2021 to 09/08/2021 and the plain English summary has been updated to reflect this change.
3. The total final enrolment number has been added.
21/04/2021: The recruitment start date has been changed from 05/04/2021 to 12/04/2021.
29/03/2021: The following changes were made to the trial record:
1. The recruitment start date was changed from 01/02/2021 to 05/04/2021.
2. The recruitment end date was changed from 30/05/2021 to 30/07/2021.
3. The primary and secondary outcome measures and exclusion criteria were updated.
23/03/2021: Trial's existence confirmed by the National Institute for Medical Research (NIMR).
