PERFIB Study
The PerFib study is a project of the Institute of Food Science and Human Nutrition at Leibniz Universität Hannover under the scientific direction of Prof. Dr. Andreas Hahn.
The project aims to investigate whether the consumption of individually tailored dietary fibres can increase the production of short-chain fatty acids by the bacteria naturally occurring in the intestine.
We cordially invite healthy men and women aged 30-65 years with a body mass index between 20 and 30 kg/m2 to participate in the study.
For more information about our study, please see "Information about the study".
You can find information about the procedure under "Procedure of the study".
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1. Information about the study
Background to the study
Dietary fibre is a component of plant foods (such as vegetables, fruits, and legumes) and is part of a balanced diet. Adequate fibre intake can reduce the risk of many diet-related diseases, especially obesity, type 2 diabetes, high blood pressure, and heart disease. One of the possible reasons for this is that certain fibres in the gut stimulate the growth of beneficial bacteria. In addition, the bacteria produce short-chain fatty acids when they utilise the fibre. However, not everyone seems to be able to utilise dietary fibre equally well, which is probably due to the individual differences in the composition of the bacteria in the intestine. Bacteria of the genus Prevotella and Bacteroides play a decisive role in the utilisation of dietary fibre. These bacteria are part of the normal bacterial composition in the intestine but occur with varying frequency. Based on the bacterial composition in the stool, people can be divided into two types, the so-called P-type (many bacteria of the genus Prevotella) and the so-called B-type (many bacteria of the genus Bacteroides).
Aim of the study
This study aims to test which dietary fibre is most suitable for P-type and B-type people concerning the production of short-chain fatty acids. Furthermore, it will be investigated whether the intake of a dietary fibre that is optimal for the individual bacterial composition compared to a suboptimal dietary fibre has a positive effect on the sugar balance. A suboptimal dietary fibre would have a less pronounced effect on the production of short-chain fatty acids than an optimal dietary fibre. Two dietary fibres are being tested, one derived from corn bran and the other from chicory roots.
Who can participate?
Healthy women and men between the ages of 30 and 65 who have no previous chronic illness can participate.
What does participation cost?
Participation is free.
Which study groups are there?
All participants in the study will take the following study products in a random order
- 1-week 3x daily intake of the dietary fibre from corn bran
- 1-week 3x daily intake of dietary fibre from chicory roots
- 1-week 3x daily intake of a placebo (glucose)
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2. Procedure of the study
How long does the study last?
The study lasts about 10 weeks. After each week of an intake, a washout period of at least 2 weeks must be observed.
How does the study work?
First, a screening examination of about 30 minutes is carried out to determine the general health status and the type of intestinal microbiome. If the participants are suitable, they will take the optimal dietary fibre, the suboptimal dietary fibre, and the placebo one after the other (in total 3 x 1 week of taking the study products). The order of the study products is random. There should be at least 2 weeks between the intake of the study products. Each week will be followed by an examination day (approx. 3.5 h). During the study day, the participants can read or work in the recreation room.
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Which examinations are carried out?
Screening:
- Stool sample to determine the intestinal microbiome
- Blood sampling to determine health status
- Questionnaire on diet and physical activity
Examination day:
- Stool sample to determine the intestinal microbiome
- Breakfast meal followed by blood sampling
- Measurement of the hydrogen content in the exhaled air
How much time do I need to participate in the study?
In total, the study lasts about 10 weeks. The screening takes about 30 minutes and you need to plan about 3.5 hours per examination day. During the examination day, you can carry out a sedentary activity such as reading or working on your laptop.
How do I become a study participant?
If you are interested in participating, you can contact us via the following contact details.
Leibniz University of Hanover
Institute of Food Science and Human Nutrition
Am Kleinen Felde 30
30167 HannoverIf you have any questions, please contact us at perfib@nutrition.uni-hannover.de or by phone at +49 511 762 3733.
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3. Contact
Director of Studies
Leibniz University of Hanover
Institute of Food Science and Human Nutrition
Prof. Dr. Andreas Hahn
Am Kleinen Felde 30
30167 Hannover
http://www.nutrition.uni-hannover.dePerson to contact
Institute of Food Science and Human Nutrition
Dr. Mattea Müller
Tel.: +49 511 762 5969
E-Mail: perfib@nutrition.uni-hannover.de -
4. Press
For editorial enquiries, please contact us at perfib@nutrition.uni-hannover.de or call +49 511 762 3733.
CAGHO-Study
The study "Effect of Calanus Oil on Glucose Homeostasis in Patients with Abdominal Obesity" (CAGHO Study) is a research project of the Institute of Food Science and Human Nutrition at Leibniz Universität Hannover under the scientific direction of Prof. Dr. Andreas Hahn.
Within the framework of a study, the influence of a novel oil with omega-3 fatty acids obtained from sustainable sources on blood sugar tolerance and insulin secretion will be investigated. The focus is on the influence on the long-term blood sugar value (HbA1c) and other health parameters - especially those of the cardiovascular system (e.g. blood pressure, and function of the blood vessels).
You can participate if you are overweight and between 30 and 75 years old. You should also be otherwise healthy. People with diabetes cannot be included in the study. However, if you suffer from prediabetes, a preliminary stage of diabetes, you can take part.
You can find more information about the study under "Information about the study".
You can find information about the procedure under "Procedure of the study".
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1. Information about the study
Background to the study
People suffering from obesity have a significantly increased risk of developing diabetes mellitus type 2 and diseases of the cardiovascular system. In addition to sufficient exercise, nutrition is crucial for prevention. Initial studies suggest that the supplementation of long-chain omega-3 fatty acids can reduce the risk of type 2 diabetes and its secondary diseases. The exact effects of omega-3 fatty acids on blood glucose control and the development of insulin resistance (decreasing insulin effectiveness) are not yet fully understood.
Aim of the study
The study will examine the effects of an omega-3 oil obtained from sustainable sources on parameters of glucose and lipid metabolism and inflammation in the body.
Who can participate?
- You can take part in our study if you
- do not have diabetes type 1 or 2
- are healthy
- are between the ages of 30 and 75
- have a waist circumference of ≥88 cm (for women) and ≥102 cm (for men)
- have a BMI of > 28 kg/m2
- are willing to take omega-3 oil or a placebo in capsule form daily for 12 weeks.
How to calculate your BMI:
(BMI = body weight (kg) / (height (m) x height (m)).
Beispiel:
Body weight = 96 kg; height = 1.82 m
→ BMI = 96 kg / (1.82 m x 1.82 m) = 28.9 kg/m2
We would appreciate it if you would fill out the questionnaire in advance if you are interested in participating. We will then check whether you are suitable for participation.
What are the study groups?
When you take part in the study, you will be randomly assigned to one of four different study groups:
- Group 1: 2 grams of omega-3 containing oil in capsules daily
- Group 2: 4 grams of omega-3 oil in capsules daily
- Group 3: 2 grams of omega-3 containing oil in capsules daily in combination with a moderate lifestyle intervention (dietary advice and 2.5 hours of moderate exercise weekly).
- Group 4 (placebo group): Placebo capsules without omega-3 containing oil daily (study participants in the placebo group will receive the omega-3 oil following the study!).
What does participation cost?
Participation is free.
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2. Procedure of the study
How long does the study last?
We will follow you for 12 weeks as part of the study.
After the end of the study, you have the option of voluntarily receiving preparations for a further 12 weeks (or for 24 weeks if you are assigned to the placebo group) and participating in further follow-up studies.
How does the study work?
During the 12-week study, we will welcome you to two examinations at the Institute of Food Science and Human Nutrition at Leibniz Universität Hannover, each of which will last about 30 minutes.
- Baseline examination (at the beginning of the study)
- Final examination (at the end of the study)
Between the two examination days you will receive the capsules and all further information (depending on the group).
If you are eligible, you will receive a tube by post to take a stool sample, which you will bring to the initial examination (baseline examination). At the initial examination, doctors and nutritionists will carry out a health and nutritional diagnosis with a blood sample.
On the same day, you will start taking the preparations. Furthermore, depending on the group, the adjustment of the diet and the moderate exercise programme will begin, if necessary.
After 12 weeks, we will invite you to the final examination. Prior to this, we will send you another set of stool samples by post, which you should bring with you to the final examination. The final examination has the same procedure as the initial examination.
After completion of the study, you have the option of a voluntary continuation of intake. This describes a follow-up observation in which the active preparation is provided to you for further intake.
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What examinations are carried out?
During the examinations, your height, weight, waist and hip circumference, and your blood pressure will be recorded. In addition, the function of your blood vessels and the composition of your body are measured. We will also use questionnaires to assess your diet, exercise, and lifestyle. We will also draw your blood and examine your stool samples. You must be fasting to have your blood taken on the days of the examination. This means you must not have eaten anything in the previous 12 hours and you must only drink calorie-free drinks.
How much time do I need to take part in the study?
We have planned about 45 minutes for you at the institute on the examination days. We will arrange a personal appointment with you so that there is no waiting time. After each examination day, you will receive a breakfast voucher for a nearby bakery.
How to become a study participant?
If you are interested in participating in the study, we ask you to measure waist circumferenceand calculate your BMI
If your waist circumference is ≥88 cm (women) or ≥102 cm (men), and you have a BMI of >28 kg/m2, the questionnaire can be completed. You will find more detailed information in the werden. Weitere ausführliche Informationen finden Sie in der subject information.
After we have positively assessed your questionnaire, we will contact you regarding an appointment for the initial examination.
Contact:
Leibniz University of Hannover
Institute of Food Science and Human NutritionPerson to contact: Wiebke Jonas
Am Kleinen Felde 30
30167 HannoverIf you have any further questions, please contact us at jonas@nutrition.uni-hannover.de or call 0511 - 762 5931.
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3. Contact
Director of Studies
Leibniz University of Hanover
Institute of Food Science and Human Nutrition
Prof. Dr. Andreas Hahn
Am Kleinen Felde 30
30167 Hanover
http://www.nutrition.uni-hannover.dePerson to contact
Leibniz University of Hanover
Institute of Food Science and Human Nutrition
Wiebke Jonas
Tel.: 0511 – 762 5931
jonas@nutrition.uni-hannover.de -
4. Press
For editorial enquiries, please contact us at jonas@nutrition.uni-hannover.de or call +49 511 - 762 5931.
