Cohort Study on Plant-based Diets (COPLANT Study) (COPLANT)

The Cohort on Plant-based Diets (COPLANT) study is a multi-centre cohort study that starts baseline recruitment from 2024 to 2027 with approximately 6,000 participants in Germany and Austria. The COPLANT study focuses on vegan (no animal products), vegetarian (no meat and fish, but dairy products and eggs), pescetarian (no meat, but fish) and omnivorous (mixed diet including all possible animal products) diets. The aim of the COPLANT study is to gain new insights on health benefits and risks as well as social, ecological and economic effects of different plant-based diets in comparison to a mixed diet. In addition to a detailed dietary survey using an app adapted to the needs of this study, the baseline examination includes measurements of body composition, bone health, cardiovascular risk factors, diabetes risk, contaminants and lifestyle. For the basic laboratory program, fasting blood, 24-hour urine collection and a stool sample are taken from all study participants. Furthermore, specific aspects of dietary behavior, physical activity and other lifestyle factors are collected via questionnaires. Follow-up studies are planned at intervals of 5, 10 and 20 years after the baseline visit.

Study Overview

• Status: Recruiting
• Conditions: Cardiovascular Diseases; Obesity; Diabetes Mellitus, Type 2; Bone Loss; Dietary Exposure; Sustainability; Vitamin Deficiency; Mineral Deficiency; Exposure

Detailed Description

The multicenter Cohort on Plant-based diets (COPLANT) study, aims to investigate the health benefits as well as short-term and long-term risks of different plant-based diets (vegan: no animal products, vegetarian: no meat and fish, but dairy products and eggs, pescetarian: no meat, but fish) compared to a mixed diet among 6,000 participants aged 18 to 69 years across German speaking countries. Currently the impact of different diets not only on health effects, but also on social, ecological and economic factors is becoming increasingly evident in areas of social justice, climate change and animal welfare. For this reason, a sustainability analysis (social, ecological and economic effects) together with findings on health effects will be included in the COPLANT study. As plant-based diets, especially vegan diets, are associated with specific risks and benefits for certain population groups such as pregnant women, breastfeeding mothers and children, COPLANT will also establish appropriate research structures for these groups and include them in the study.

The detailed consumption survey of all study participants is one of the main pillars of the planned study. Of particular importance is the dietary assessment of novel vegan and vegetarian foods, thus an app adapted to the needs of this study was developed. The characterisation of external and internal intakes of nutrients and contaminants within a particular diet will be examined. Large epidemiological projects currently underway in Germany, such as the NAKO Health Study, are unable to answer these questions. In order to prospectively investigate links between diet and the later occurrence of common diseases such as type 2 diabetes, cardiovascular diseases and cancer, the study participants should be followed up for at least 20 years if third-party funding is successfully acquired.

The study is to be conducted in study centers at the Federal Institute for Risk Assessment (BfR), Berlin, the Max Rubner-Institut (MRI) in Karlsruhe, the Rheinische Friedrich-Wilhelms University in Bonn, the Friedrich Schiller University Jena, the Research Institute for Plant-Based Nutrition in Giessen, in cooperation with the Justus Liebig University Giessen and at the universities of Heidelberg, Regensburg and Vienna. Furthermore, the basic examination includes measurements of body composition, bone health, cardiovascular risk factors, diabetes risk, contaminants and lifestyle. Specific aspects of dietary behavior, physical activity and other lifestyle factors will be assessed using questionnaires. For the basic laboratory program, fasting blood, 24-hour urine collection and a stool sample are taken from all study participants.

Participants will be recruited for the baseline study from 2024 to 2027. Follow-up visits are planned at intervals of 5, 10 and 20 years.

• Study Type: Observational
• Enrollment (Estimated): 6000

Contacts and Locations

• Study Contact: Name: Cornelia Weikert, Prof; Phone Number: +49 30 184155000; Email: Cornelia.Weikert@bfr.bund.de
• Study Contact Backup: Name: Christine Dawczynski, PhD; Phone Number: +49 3641 949656; Email: christine.dawczynski@uni-jena.de

Study Locations

• Austria
  • Vienna, Austria, 1090
    • Recruiting
    • University Vienna
    • Contact: Maria Wakolbinger, Prof; Email: maria.wakolbinger@meduniwien.ac.at
    • Contact: Tilman Kühn, Prof; Email: tilman.kuehn@univie.ac.at
• Germany
  • Berlin, Germany, 10589
    • Recruiting
    • The German Federal Institut for Risk Assessment
    • Contact: Cornelia Weikert, Prof; Phone Number: +49 30 1841255000; Email: Cornelia.Weikert@bfr.bund.de
  • Bonn, Germany
    • Recruiting
    • University Bonn
    • Contact: Ute Nöthlings, Prof; Email: noethlings@uni-bonn.de
  • Gießen, Germany, 35444
    • Not yet recruiting
    • Research Institute for Plant-Based Nutrition, Gießen
    • Contact: Markus Keller, PhD; Email: keller@ifpe-giessen.de
  • Heidelberg, Germany, 69120
    • Not yet recruiting
    • University Heidelberg
    • Contact: Ina Danquah; Email: ina.danquah@uni-heidelberg.de
  • Regensburg, Germany, 93053
    • Recruiting
    • University Regensburg
    • Contact: Michael Leitzmann, Prof; Email: Michael.Leitzmann@klinik.uni-regensburg.de
    • Contact: Beate Fischer; Email: Beate.Fischer@klinik.uni-regensburg.de
  • Baden-Württemberg
    • Karlsruhe, Baden-Württemberg, Germany, 76131
      • Recruiting
      • Max Rubner-Institut
      • Contact: Benedikt Merz, PhD; Email: benedikt.merz@mri.bund.de
  • Thuringia
    • Jena, Thuringia, Germany, 07743
      • Recruiting
      • Friedrich-Schiller University
      • Contact: Christine Dawczynski, PhD; Phone Number: +49 3641 949656; Email: christine.dawczynski@uni-jena.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Vegans - no consumption of animal products (less than one exception per month)

Vegetarians

• no consumption of meat and fish (less than one exception per month)
• consumption of eggs and/or dairy products (at least once a month)

Pescetarians

• no consumption of meat (less than one exception per month)
• consumption of fish (at least once a month)
• consumption of eggs or dairy products possible

Omnivores/ mixed diet - group of non-exposed persons or control group

- consumption of meat or sausage (at least once a month).

Description

Inclusion Criteria:

• age between 18 and 69 years at recruitment (age-stratified recruitment in four age groups (18 to 29, 30 to 39, 40 to 49 and 50 to 69 years) which should be equally distributed across the four diets)
• following their current diet for at least one year
• health insured
• are willing to have blood taken (adults)
• are willing and able to complete questionnaires
• only at Berlin, Jena, Giessen and Karlsruhe sites: pregnant and breastfeeding women were recruited (shortened examination programm)
• only at the Regensburg, Heidelberg, Bonn and Vienna sites: are neither pregnant nor breastfeeding at the time of recruitment
• only at Berlin and Karlsruhe sites: children of adult participants (shortened examination programm without collection of blood, urine, and stool)
• are able to give informed consent to participate in the study
• have given their consent to participate in the COPLANT study

Exclusion Criteria:

• who can no longer be contacted
• who withdraw their consent to participate in the study

Study Plan

How is the study designed?

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort
vegans; vegan diet: no products of animal origin
vegetarians; vegetarian diet: no meat and fish, but dairy products and eggs
pescetarians; pescetarian diet: no meat, but fish
mixed diet; mixed diet: plant-based foods and animal-based foods

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of diabetes type 2	Incidence of diabetes type 2	5, 10, 20 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of cardiovascular diseases	Incidence of cardiovascular diseases	10, 20 years
Incidence of cancer	Incidence of cancer	10, 20 years
Vitamin B12	Vitamin B12 (pmol/l)	Baseline
Holo-transcobalamine	Holo-transcobalamine (pmol/l),	Baseline
Homocysteine	Homocysteine (µmol/l)	Baseline
Methylmalonic acid	Methylmalonic acid (µg/l)	Baseline
Vitamin B1 status	Vitamin B1 (nmol/l)	Baseline
Vitamin B2 status	Vitamin B2 (µg/l)	Baseline
Vitamin B6 status	Vitamin B6 (nmol/l)	Baseline
Vitamin C status	Vitamin C (mg/l)	Baseline
Vitamin D status	Vitamin D (nmol/l)	Baseline
Vitamin E status	Vitamin E (µmol/l)	Baseline
Iron	Iron (µmol/l)	Baseline
Ferritin	Ferritin (µg/l)	Baseline
Transferrin	Transferrin (mg/dl)	Baseline
Zinc status	Zinc (µg/l)	Baseline
Selenium status	Selenium (µg/l)	Baseline
Iodine status	Iodine (µg/l)	Baseline
Blood pressure	Systolic blood pressure (mm Hg), diastolic blood pressure (mm Hg)	Baseline
Blood lipids	Total cholesterol, LDL, HDL, triacylglycerides (mmol/l)	Baseline
Fasting insulin	Fasting insulin (mU/l)	Baseline
Fasting glucose	Fasting glucose (mmol/l)	Baseline
Glycated hemoglobin (HbA1c)	HbA1c (%)	Baseline
C-peptide	C-peptide (ng/ml)	Baseline
Osteocalcin	Osteocalcin (ng/ml)	Baseline
Ostase	Ostase (µg/l)	Baseline
Parathormone	Parathormone (ng/l)	Baseline
N-terminal propeptide of type I procollagen (PINP)	PINP (ng/ml)	Baseline
C-terminal telopeptide of type I collagen (CTX)	CTX (ng/ml)	Baseline
Creatinine	Creatinine (mmol/24h)	Baseline
Uric acid	Uric acid (mg/24h)	Baseline
Cytstatin C	Cytstatin C (mg/l)	Baseline
Thyroid stimulating hormone (TSH)	TSH (mU/l)	Baseline
Free triiodothyronine (fT3)	fT3 (pmol/l)	Baseline
Free thyroxine (fT4)	fT4 (pmol/l)	Baseline
Energy intake	Calories per day	Baseline
Nutrient intake	Milligramm per day	Baseline
Intake of dietary supplements	Frequencies per day	Baseline
Intake of medication	Frequencies per day	Baseline
Body fat	Body fat (kg)	Baseline
Skeletal muscle mass	Skeletal muscle mass (kg)	Baseline
Total Body Water	Total Body Water (l)	Baseline

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heavy metals	Arsenic, lead, cadmium (µg/l)	Baseline
Halogenated, polycyclic aromatic hydrocarbons (dioxins)	Dioxins (ng/g lipid)	Baseline
Mycotoxins	Mycotoxins (ng/ml)	Baseline
Per- and polyfluoroalkyl substances (PFAS)	PFAS (ng/ml)	Baseline
Microbiome	16S rRNA sequencing	Baseline

Collaborators and Investigators

• Sponsor: German Federal Institute for Risk Assessment
• Collaborators: University of Vienna; Heidelberg University; University of Jena; University of Regensburg; University of Bonn; Max Rubner-Institut; Research Institute for Plant-Based Nutrition
• Investigators: Principal Investigator: Ute Nöthlings, Prof, University Bonn; Principal Investigator: Christine Dawczynski, PhD, University Jena; Principal Investigator: Markus Keller, PhD, Research Institute for Plant-based Nutrition (IFPE); Principal Investigator: Michael Leitzmann, Prof, University Regensburg; Principal Investigator: Ina Danquah, Prof, University Heidelberg; Principal Investigator: Maria Wakolbinger, Prof, University Vienna; Principal Investigator: Tilman Kühn, Prof, University Vienna; Principal Investigator: Beate Fischer, PhD, University Regensburg; Principal Investigator: Benedikt Merz, PhD, Max Rubner-Institut; Principal Investigator: Cornelia Weikert, Prof, Federal Institut for Risk Assessment

Publications and helpful links

Helpful Links

• summary

Study record dates

Study Major Dates

• Study Start (Actual): April 9, 2024
• Primary Completion (Estimated): March 31, 2027
• Study Completion (Estimated): March 31, 2047

Study Registration Dates

• First Submitted: March 1, 2024
• First Submitted That Met QC Criteria: March 14, 2024
• First Posted (Actual): March 21, 2024

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 13, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: biomarker; children; mental health; cardiovascular risk; pregnancy; inflammation; body composition; microbiota; adults; metabolomics; vegetarian; vegan; vitamins; bone health; diabetes type 2; minerals; sustainability; pescetarian; omnivor; multicenter cohort; contaminants; thyroid gland health; breast feeding time
• Additional Relevant MeSH Terms: Endocrine System Diseases; Nutrition Disorders; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Deficiency Diseases; Malnutrition; Diabetes Mellitus, Type 2; Cardiovascular Diseases; Avitaminosis
• Other Study ID Numbers: 01 (Miami VAHS)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: In accordance with the informed consent of the COPLANT participants, pseudonymised study data could be provided to external researchers upon request for cooperation or data-use purposes. In this case, a cooperation or data use agreement must be concluded in advance. The use of COPLANT study data is therefore only possible with a detailed prior justification of its scientific purpose and after agreement of the steering commitee of the COPLANT study.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No