Obesity, Overweight
Conditions
Keywords
Overweight and Obesity, Whey Protein, Dietary Pattern
Brief summary
This study compares the effects of two calorie-restricted diets-one with whey protein supplementation and one without-and a health education control group on weight and metabolic parameters in overweight and obese individuals, with the aim of informing dietary intervention strategies for this population.
Detailed description
The prevalence of overweight and obesity has been rising globally due to lifestyle and dietary changes. According to the "Report on the Status of Nutrition and Chronic Diseases among Chinese Residents (2020)", the proportion of overweight and obese adults in China has exceeded 50%. Overweight and obesity are not only major risk factors for chronic diseases such as diabetes and cardiovascular diseases but are also closely related to the increased risk of premature death. They have become one of the most serious public health problems. Dietary intervention is a fundamental approach to the treatment of overweight and obesity. In recent years, the impact of different dietary structures on overweight and obesity has received increasing attention from researchers. The "Chinese Guidelines for Medical Nutrition Therapy of Overweight/Obesity (2021)" points out that a high-protein diet can reduce hunger, increase satiety, and increase resting energy expenditure, which is beneficial for weight loss and improving glucose homeostasis and blood lipid levels in overweight and obese patients. Studies have shown that increasing dairy intake during energy-restricted dietary intervention may help enhance satiety and reduce more body weight and fat mass. Whey protein is the protein component retained in the supernatant during the separation and precipitation of casein, and it is rich in essential amino acids. The proportion of branched-chain amino acids in its amino acid composition pattern is relatively high, which can promote the construction and repair of human tissue structure. Studies have shown that whey protein supplements can help overweight and obese patients lose weight and body fat, maintain lean body mass, and to some extent improve cardiovascular disease risk factors such as blood pressure and blood glucose levels. However, the potential mechanisms of action are not clear. In addition, the role of whey protein in the overweight and obese population in China remains to be studied. Based on this, this project designed two dietary models: a whey protein powder-supplemented energy-restricted high-protein diet and an energy-restricted balanced diet. They were compared with a health education control group to study the effects of whey protein powder on weight and metabolic indicators in overweight and obese patients, in order to provide a reference for dietary intervention in overweight and obese patients.
Interventions
DIETARY_SUPPLEMENTwhey protein powder
The intervention period lasted for 12 weeks. During this time, Participants received dietary guidance from researchers. The whey protein group underwent a 30% energy reduction diet with a macronutrient distribution of 45%-50% carbohydrates, 30% fat, and 20%-25% protein. Participants consumed 13 grams of whey protein powder twice daily, with breakfast and afternoon snacks, partially replacing staple foods.
BEHAVIORALcalorie-restricted balanced diet
The intervention period lasted for 12 weeks. During this time, Participants received dietary guidance from researchers. The calorie-restricted balanced diet group underwent a 30% energy reduction diet with a macronutrient distribution of 55% carbohydrates, 30% fat, and 15% protein.
BEHAVIORALhealth education
The intervention period lasted for 12 weeks. During this time, Participants received dietary guidance from researchers. The health education control diet group followed an unrestricted energy healthy diet plan with a macronutrient distribution of 50% -65%carbohydrates, 20%-30% fat, and 10%-15% protein.
Sponsors
Second Affiliated Hospital, School of Medicine, Zhejiang University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
25 Years to 35 Years
Healthy volunteers
No
Inclusion criteria
* Age 25-35 years old, no gender restrictions * Body mass index (BMI) ≥ 24 kg/m² * Voluntary consent and signed informed consent form
Exclusion criteria
* Age \< 25 years or \> 35 years * Current use of medications that may affect weight or energy balance (e.g., lipid-lowering drugs, antidiabetic drugs, appetite suppressants), or other protein supplements * Presence of acute or chronic viral hepatitis, abnormal liver function (ALT or/and AST \> 3 times the upper limit of normal), kidney disease (serum creatinine \> upper limit of normal), diabetes, malignant tumors, or cardiovascular diseases * Gastrointestinal disorders that affect food digestion and absorption (e.g., chronic diarrhea, constipation, severe gastrointestinal inflammation, active peptic ulcer disease, post-gastrointestinal surgery) * Psychiatric disorders * Allergies to product ingredients or presence of inborn metabolic disorders * Pregnancy or lactation * Other conditions deemed unsuitable for participation in the study by the researchers (e.g., severe diseases not listed in the
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Body weight | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Measured after fasting and voiding, without shoes, in light clothing, using a standard scale |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Skeletal muscle mass | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Measured by Bioelectrical impedance analysis |
| Body fat mass | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Measured by Bioelectrical impedance analysis |
| Body fat percentage | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Measured by Bioelectrical impedance analysis |
| Visceral fat area | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Measured by Bioelectrical impedance analysis |
| Handgrip strength | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Measure the grip strength of the dominant hand, take the maximum value of two attempts, and record to the nearest 0.1 kg |
| Fasting glucose level | Change from baseline to 12 weeks | Collect fasting venous blood (after at least 8 hours of fasting) from subjects to measure fasting blood glucose |
| Insulin-resistance status | Change from baseline to 12 weeks | Measured with the use of the homeostasis model assessment of insulin resistance (HOMA-IR) |
| Fasting insulin | Change from baseline to 12 weeks | Collect fasting venous blood (after at least 8 hours of fasting) from subjects to measure fasting insulin |
| Serum lipids | Change from baseline to 12 weeks | Fasting venous blood (after 8 hours of fasting) is collected from the subjects. Serum levels of total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) are measured |
| Renal function | Change from baseline to 12 weeks | Collect fasting venous blood (after at least 8 hours of fasting) from subjects to measure serum creatinine (Cr) and blood urea nitrogen (BUN) . The estimated glomerular filtration rate (eGFR) is calculated using the CKD-EPI or MDRD formula based on serum creatinine, age, sex, and race. |
| Hunger rating | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Using a 5-point Likert scale (Not at All, Somewhat, Moderately, Very, Extremely) |
| Diet Satisfaction | Baseline; after 4-week intervention; after 8-week intervention；after 12-week intervention | Using a 5-point Likert scale (Not at All, Somewhat, Moderately, Very, Extremely) |
Countries
China
Outcome results
None listed