Total Energy Expenditure in Healthy Chinese Populations: A Nationwide Study Using the Doubly Labelled Water Method
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 240
- 试验地点
- 7
- 主要终点
- Fat-free mass
研究概览
简要总结
Between 1990 and 2022, the global prevalence of obesity more than doubled, representing a critical public health concern. China has mirrored this trend, with rapidly increasing rates of overweight and obesity across all age groups. According to the 'Report on Chinese Residents' Nutrition and Chronic Diseases (2020)', 50.7% of Chinese adults are now classified as overweight or obese. Among children and adolescents aged 6 to 17 years, data from the 'Atlas of Nutrition and Health Status of Chinese Children' indicates that the prevalence of overweight and obesity has reached 26.5%.
Obesity is associated with a broad spectrum of adverse health outcomes across the life course. In children, excess adiposity negatively affects skeletal maturation, neurocognitive development, and psychosocial well-being, while also increasing the likelihood of obesity and metabolic dysfunction in adulthood. In adults, obesity is a major risk factor for a range of non-communicable diseases (NCDs), including type 2 diabetes mellitus, hypertension, cardiovascular disease, non-alcoholic fatty liver disease, osteoarthritis, certain cancers, and all-cause premature mortality. Beyond its health implications, obesity imposes substantial economic and social burdens, including increased healthcare expenditure and reduced workforce productivity.
The etiology of the obesity epidemic is multifactorial and remains under active investigation. Hypotheses center around a chronic imbalance between energy intake and expenditure, driven by behavioral, environmental, and physiological factors. Notably, decreased physical activity associated with sedentary lifestyles and increased consumption of energy-dense, nutrient-poor foods have been implicated as key contributors. However, the relative contributions of reduced energy expenditure versus increased energy intake remain insufficiently quantified at the population level. Accurate assessment of total energy expenditure (TEE) is therefore essential to elucidate the energy dynamics underlying the obesity epidemic.
Current approaches for estimating population-level energy and food requirements are often based on indirect methods with limited precision. The doubly labelled water (DLW) technique, which quantifies TEE through measurement of isotope elimination rates (^2H and ^18O), remains the gold standard for assessing free-living energy expenditure. However, its application has been predominantly confined to high-income countries with well-established research infrastructure. In contrast, the use of DLW in low- and middle-income countries-including China-remains minimal, resulting in critical data gaps that hinder the development of context-specific dietary recommendations and energy requirement models.
To address these limitations, this study will apply the DLW method to measure TEE in healthy children and adults in China. In parallel, the study will assess key modulators of energy metabolism, including anthropometric and physiological parameters, gut microbiota composition, habitual physical activity, and ambient temperature exposure. The resulting dataset will provide high-resolution, population-specific evidence to inform national dietary reference intakes and support the formulation of evidence-based public health strategies aimed at obesity prevention and metabolic health promotion.
详细描述
The investigators will recruit healthy children aged 7 to 18 and healthy adults aged 30 to 60 from within the country to participate in a study to explore their energy requirements and factors.
The following measurements will be conducted in both children and adults:
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Study Details Anthropometric Measurements
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Height: Height will be measured using a Seca 217 stadiometer. Participants will stand barefoot with feet approximately 60° apart. Heels, sacrum, and shoulder blades will be placed against the stadiometer's vertical rod. The head will be aligned so that the upper margin of the ear canal is level with the lower margin of the eye socket. The horizontal plate will be lowered gently to rest on the crown of the head. Two measurements will be taken and averaged; values will be recorded to the nearest 0.1 cm.
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Body Weight: After an overnight fast, body weight will be measured in the morning using a calibrated TANITA MC-780 scale. Participants will wear light clothing and no shoes.
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Waist Circumference: Waist circumference will be measured at the midpoint between the iliac crest and the lower edge of the 12th rib. Participants will stand with feet 25-30 cm apart and body weight evenly distributed. A flexible tape will be wrapped snugly (without compression), and two measurements will be averaged to the nearest 0.1 cm.
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Hip Circumference: Hip circumference will be measured with the participant standing straight, legs together, arms relaxed. The tape will be placed horizontally at the level of the pubic symphysis and the most prominent part of the buttocks. Two measurements will be taken and averaged.
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Thigh Circumference: Thigh circumference will be measured with the participant standing straight, legs together, arms relaxed. The tape measure should be wrapped horizontally around the thickest part of the thigh (usually about 10 centimeters below the hip crease), closely adhering to the skin but not pressing on the soft tissue. The average of two measurements will be taken, accurate to 0.1 cm.
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Neck Circumference: Neck circumference will be measured with the participant keeping their head straight and drooping their shoulders naturally. The tape measure should be placed horizontally at the lower edge of the thyroid cartilage (Adam's apple) in front of the neck, passing through the lower part of the bilateral occipital protuberances on both sides. The measurement should be taken twice and the average value will be obtained, accurate to 0.1 cm.
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Blood Pressure: Blood pressure will be measured with the participant relaxing shoulders, straightening backs, sitting upright and placing arms flat on the table at the same level as the heart. Participants will rest quietly for more than 5-10 minutes before measuring blood pressure. The blood pressure cuff will tie at a distance of one finger above the elbow, with the center point level with the heart. Record the blood pressure at the end.
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Heart Rate: Heart rate will be measured with the participant relaxing shoulders, straightening backs, sitting upright and placing arms flat on the table at the same level as the heart. Participants will rest quietly for more than 5-10 minutes before measuring blood pressure. The blood pressure cuff will tie at a distance of one finger above the elbow, with the center point level with the heart. Record the heart rate at the end.
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Abdominal Fat: Abdominal fat will be measured with the participant lying on their back and exposing abdomen as instructed by the doctor. Trained personnel will use the DW-360 to measure participants' abdominal fat.
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Bone Mineral Density: Bone mineral density will be measured with the participant lying flat on their back and remaining still as instructed by the technician. Professional personnel will use the Dual Energy X-ray (DXA) scanner to measure participants' bone mineral density.
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Blood biochemistry test and gut microbiota detection
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Blood Index: Blood index will be measured by taking blood samples from participants after a 10-hour fast, including red blood cell (RBC), white blood cells (WBC), hemoglobin (HB), etc.
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Lipid Profile: Lipid profile will be measured by taking blood samples from participants after a 10-hour fast, including total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C).
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Liver Function: Liver function will be measured by taking blood samples from participants after a 10-hour fast, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), direct bilirubin (DB) and indirect bilirubin (IB), etc.
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Renal Function: Renal function will be measured by taking blood samples from participants after a 10-hour fast, including blood urea nitrogen (BUN), serum uric acid (SUA) and serum creatinine (SCr).
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Vitamin D levels: Vitamin D levels will be measured by taking blood samples from non-fasting participants.
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Gut Microbiota: Gut microbiota is obtained by collecting fecal samples from participants.
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Questionnaires
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 7 Years 至 60 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy participants
排除标准
- •Exclusion Criteria:
- •Malnutrient as defined by the Chinese national standards WS/T456-2014 and WS/T 586-2018
- •Nutritional deficiencies
- •Acute illness within the past 7 days
- •Chronic diseases
- •Cardiovascular diseases
- •Diabetes mellitus or any form of metabolic disorders
- •Type 1 or Type 2 diabetes
- •Metabolic syndrome
- •Hyperlipidemia
- •Dyslipidemia
- •Renal diseases
- •Chronic kidney disease
- •Nephrotic syndrome
- •Musculoskeletal injuries
- •Disabilities
结局指标
主要结局
Fat-free mass
时间窗: About 3 minutes.
Fat-free mass in kilograms will be measured by TANITA.
Muscle mass
时间窗: About 3 minutes.
Muscle mass in kilograms will be measured by TANITA.
Total body water
时间窗: About 3 minutes.
Total body water in kilograms will be measured by TANITA.
Abdominal fat
时间窗: About 20 minutes.
Abdominal fat will be measured in using a portable ultrasound device (DW-360).
Fat percentage
时间窗: About 3 minutes.
Fat percentage will be measured by TANITA.
Height
时间窗: About 3 minutes.
Height in meters will be measured by Leicester stadiometer (Seca 217, Germany) and reported to two decimal places.
Weight
时间窗: About 5 minutes.
Weight in kilograms will be measured by TANITA.
BMI
时间窗: About 10 minutes (calculated)
BMI values in kg/m2 will be calculated from weight measured by TANITA and height measured by Leicester stadiometer (Seca 217, Germany).
Fat mass
时间窗: About 3 minutes.
Fat mass in kilograms will be measured by TANITA.
Waist circumference
时间窗: About 5 minutes.
Waist circumference(measured in centimeters) will be obtained using a flexible tape measure following standardized protocols.
Hip circumference
时间窗: About 5 minutes.
Hip circumference(measured in centimeters) will be obtained using a flexible tape measure following standardized protocols.
Thigh circumference
时间窗: About 5 minutes.
Thigh circumference(measured in centimeters) will be obtained using a flexible tape measure following standardized protocols.
Neck circumference
时间窗: About 5 minutes.
Neck circumference(measured in centimeters) will be obtained using a flexible tape measure following standardized protocols.
Heart rate
时间窗: About 10 minutes.
Heart rate will be measured in using a standardized blood pressure monitor.
Blood pressure
时间窗: About 10 minutes.
Blood pressure will be measured using a standardized blood pressure monitor, with recordings of both systolic and diastolic values.
Skin carotenoid concentration
时间窗: About 5 minutes.
Skin carotenoid concentration will be measured in using the Veggie Meter，and the results will be expressed as Standard Point Score (SPS), typically ranging from 0 to 800 SPS. Higher SPS values indicate higher skin carotenoid concentration.
Red Blood Cell Count
时间窗: About 10 minutes.
Red blood cell count will be measured in fasting blood samples.
White Blood Cell Count
时间窗: About 10 minutes.
White blood cell count will be measured in fasting blood samples.
Hemoglobin
时间窗: About 10 minutes.
Hemoglobin concentration will be measured in fasting blood samples, reported in grams per liter (g/L).
Total Cholesterol
时间窗: About 10 minutes.
Total cholesterol concentration will be measured in fasting blood samples, reported in millimoles per liter (mmol/L).
Bone mineral density
时间窗: About 20 minutes.
Bone mineral density will be measured using the Dual-energy X-ray Absorptiometry (DXA) device.
Mid-upper arm circumference
时间窗: About 5 minutes.
Mid-upper arm circumference (measured in centimeters) will be obtained using a flexible tape measure following standardized protocols.
Grip strength
时间窗: About 5 minutes.
Grip strength will be obtained using a dynamometer(CAMRY, EH101).
Triglycerides
时间窗: About 10 minutes.
Triglycerides concentration will be measured in fasting blood samples, reported in millimoles per liter (mmol/L).
High-Density Lipoprotein Cholesterol
时间窗: About 10 minutes.
High-density lipoprotein cholesterol (HDL-C) concentration will be measured in fasting blood samples, reported in millimoles per liter (mmol/L).
Low-Density Lipoprotein Cholesterol
时间窗: About 10 minutes.
Low-density lipoprotein cholesterol (LDL-C) concentration will be measured in fasting blood samples, reported in millimoles per liter (mmol/L).
Alanine Aminotransferase
时间窗: About 10 minutes.
Alanine aminotransferase (ALT) activity will be measured in fasting blood samples, reported in units per liter (U/L).
Aspartate Aminotransferase
时间窗: About 10 minutes.
Aspartate aminotransferase (AST) activity will be measured in fasting blood samples, reported in units per liter (U/L).
Total Bilirubin
时间窗: About 10 minutes.
Total bilirubin concentration will be measured in fasting blood samples, reported in micromoles per liter (μmol/L).
Direct Bilirubin
时间窗: About 10 minutes.
Direct bilirubin concentration will be measured in fasting blood samples, reported in micromoles per liter (μmol/L).
Indirect Bilirubin
时间窗: About 10 minutes.
Indirect bilirubin concentration will be measured in fasting blood samples, reported in micromoles per liter (μmol/L).
Blood Urea Nitrogen
时间窗: About 10 minutes.
Blood urea nitrogen (BUN) concentration will be measured in fasting blood samples, reported in millimoles per liter (mmol/L).
Serum Uric Acid
时间窗: About 10 minutes.
Serum uric acid concentration will be measured in fasting blood samples, reported in micromoles per liter (μmol/L).
Serum Creatinine
时间窗: About 10 minutes.
Serum creatinine concentration will be measured in fasting blood samples, reported in micromoles per liter (μmol/L).
Vitamin D levels
时间窗: About 10 minutes.
Vitamin D levels will be obtained by collecting blood samples.
Gut microbiota
时间窗: About 10 minutes.
Gut microbiota will be obtained by collecting fecal samples.
Secondary sexual characteristics
时间窗: About 5 minutes.
The Tanner stages are used to assess the development of secondary sexual characteristics and are divided into five stages. For boys, the evaluation includes pubic hair development and genital development (including testicular and penile growth). For girls, the evaluation includes pubic hair development and breast development (thelarche).
Basal metabolic rate
时间窗: About 30 minutes.
The basal metabolic rate in kcal or MJ will be measured by respiratory indirect calorimetry (Cosmed).
Total energy expenditure
时间窗: About 14 days.
Total energy expenditure in kcal or MJ will be measured using the DLW method. TEE will then be calculated using mean CO2 production using the Weir equation.
Environmental temperature
时间窗: About 14 days.
The iButton (DS1921G) monitors will be provided for the assessment of both indoor and outdoor temperature of their living environment, measured in degrees Celsius (°C).
Physical activity energy expenditure
时间窗: About 14 days.
Physical activity energy expenditure will be recorded using a GT3X accelerometer worn at the waist for a consecutive period of 14 days, with results expressed in kilocalories (kcal) or megajoules (MJ) per day.
Total moderate-to-vigorous physical activity (MVPA)
时间窗: About 14 days.
Total MVPA will be recorded using a GT3X accelerometer worn at the waist for a consecutive period of 14 days, with results expressed in minutes per day (min/day).
Vector magnitude counts
时间窗: About 14 days.
Vector magnitude counts will be recorded using a GT3X accelerometer worn at the waist for a consecutive period of 14 days, with results expressed as counts per minute (cpm). Higher cpm values indicate greater overall physical activity intensity, reflecting the average level of movement during the monitoring period.
次要结局
未报告次要终点
研究者
Xueying Zhang
Associate researcher
Shenzhen Institutes of Advanced Technology ,Chinese Academy of Sciences