Effects of Plant-based Diets on Body Weight and Selected Metabolic Parameters in Obese Patients: a Randomised Controlled Trial of Five Different Diets
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 90
- Locations
- 1
- Primary Endpoint
- Body weight
Study Overview
Brief Summary
The aim of the study is to determine the optimal plant-based dietary model in terms of weight loss and health that would be both acceptable and environmentally friendly dietary model based on limiting the consumption of meat and animal products. Such findings will lead to new knowledge and allow us to formulate new principles for the nutritional treatment of people suffering from obesity.
Detailed Description
Obesity is not only one of the most serious health problems in the world, it is also associated with an increased risk of many other diseases. Despite many preventive measures, the number of people suffering from obesity is constantly increasing, also in Poland. One of the integral elements of treatment is a change in lifestyle, including a change in eating habits. In this context, new dietary models are constantly being considered and eagerly adopted by patients. These are not always rational and evidence-based choices. What's more, what we eat is not only important for our health, but also for the planet. Recently, high-fat diets with a significant carbon footprint have gained popularity.
It is therefore worth considering more plant-based dietary models in the treatment of obesity and its associated disorders. Such a change can simultaneously help reduce greenhouse gas emissions and improve environmental quality, as well as benefit our health - both directly and indirectly.
There is a growing body of scientific evidence suggesting that limiting meat consumption may be beneficial to health, leading to weight loss, improvements in selected cardiovascular risk parameters and inflammation. However, many questions remain.
For this reason, more plant-based dietary patterns are worth considering in the treatment of obesity and its accompanying disorders. There is growing scientific evidence that limiting meat consumption promotes good health. It has been shown that the implementation of a vegetarian diet can result in weight loss, as well as help in maintaining optimal weight levels more effectively in the long term. This is extremely important for people suffering from obesity. Adherence to meat-restricted diets is also associated with other health benefits, which include an improved lipid profile and other cardiovascular risk parameters, as well as beneficial effects on inflammation and oxidative stress parameters.
Currently, there are only a few intervention studies available that have investigated the effectiveness of plant-based diets in a population of obese adults who previously have not restricted their meat consumption. Most of the studies concern vegetarians, whose awareness of taking care of their diet and lifestyle is, after all, much higher. To some extent, this may explain such optimistic conclusions from observational studies. It is not the only issue associated with research focused on plant-based diets. In experimental studies, the results of dietary interventions are very often compared with no intervention whatsoever. It would therefore be interesting to verify the effectiveness of a vegan or vegetarian diet against current dietary recommendations or another health-promoting dietary pattern - the Mediterranean diet. After all, vegan or vegetarian diets are elimination diets. Should they be recommended for the treatment of obesity and disorders associated with it? Do body weight, cholesterol and glucose levels decrease faster? What risks do they entail and are they difficult to implement? The investigators only know the answers to some of these questions.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to 60 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Age >18 years (adults able to give informed consent to participate in the study) ≤ 60 years of age
- •BMI >30 kg/m2 or BMI 25-29.9 kg/m2 with waist circumference in women 88 cm, in men 94cm.
Exclusion Criteria
- •age <18 years and >60 years,
- •severe medical conditions, including alcoholism, major and extensive surgery, chronic kidney and liver disease, history of myocardial infarction, unstable angina pectoris within the last 6 months, history of stroke within the last 6 months, cancer within the last 5 years,
- •psychiatric condition preventing participation in the study and cooperation with the investigators,
- •use of enteral or parenteral nutrition,
- •use of medications that cause significant weight loss (e.g., GLP-1 analogues)
- •pregnancy or breast feeding,
- •attempts to change dietary habits, including reduction of caloric intake and elimination of meat and animal products in the past 6 months,
- •lack of consent to participate in the study.
Arms & Interventions
Mediterranean diet
This heart-healthy eating plan emphasizes healthy fats, whole grains, fruits, vegetables, beans, nuts and seeds.
Intervention: Mediterranean diet (Other)
Planetary diet
Defined in the EAT-Lancet Commission report
Intervention: Planetary diet (Other)
Lactovegetarian diet
A variation of vegetarianism that excludes meat, poultry, seafood, and eggs, but includes dairy products.
Intervention: Lactovegetarian diet (Other)
Vegan diet
Based on plants (such as vegetables, grains, nuts and fruits) and foods made from plants.
Intervention: Vegan diet (Other)
Control diet
Based on the current national dietary recommendations for the Polish population
Intervention: Control diet (Other)
Outcomes
Primary Outcomes
Body weight
Time Frame: After 12 weeks of dietary intervention
Mean incremental difference in body weight (kg) change of 1% consecutively between each of the five groups (corresponding to an effect size of 0.57)
Secondary Outcomes
- Glucose level changes(After 12 weeks of intervention.)
- Waist and hip circumference(After 12 weeks of intervention)
- Waist-Hip Ratio (WHR)(After 12 weeks of intervention)
- Body fat mass(After 12 weeks of intervention])
- Lipids profile(After 12 weeks of intervention)
- Blood Uric Acid(After 12 weeks of intervention)
- Serum Micronutrient Levels(After 12 weeks of intervention)
- Liver Enzymes Activity(After 12 weeks of intervention)
- Inflammatory Markers(After 12 weeks of intervention)
- Insulin level changes(After 12 weeks of intervention)
Investigators
ANNA JAGIELSKA
Principal Investigator
Medical University of Warsaw