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NCT Number: NCT07054294

Total Energy Expenditure Across the Life Course in Low-and Middle-Income Countries -- Chinese Children

By 2050, there will be 9 billion people on earth. It will be necessary to feed them to avoid the population catastrophe predicted by Malthus 150 years ago. Yet a major issue facing governments is that the current method by which food demands are estimated is widely acknowledged as completely inaccurate. An accurate method is available. It is based on measurements of isotope elimination, called the doubly labelled water (DLW) method. In 2018, the International Atomic Energy Agency (IAEA) hosted and compiled a database of measurements using this technique. It showed that the use of the DLW method has been mostly restricted to the USA and Western Europe. It has rarely been applied across Africa and Asia. The database also focused on adults, leaving much unknown about the energy balance in children and adolescents. There is a clear need to fill this gap in knowledge, providing information that governments across Low- and Middle-Income countries can use to forecast future food demands. In China, the prevalence of overweight and obesity among children and adolescents is increasing. In 2009, 22.1% of Chinese youth aged 7-17 years were either overweight or obese, according to the China Health and Nutrition Survey. The obesity rate has increased fourfold since 1995. One of the most concerning problems is the persistence of childhood obesity into adulthood. The causes of this obesity epidemic are strongly disputed, with some suggesting it is due to increasingly sedentary lifestyles (computers, cars, phones, etc.), while others suggest it is mostly due to changing food patterns (junk food and sugar-sweetened beverages). Measuring energy expenditure in children and adolescents in China will address whether declining expenditure due to reduced physical activity is a key cause of the epidemic. Most measurements come from urban populations, leaving rural populations greatly underrepresented.

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Key information

Conditions

Nutrition, Healthy

Age range

7 year–13 year

Sex eligibility

All sexes

Study type

Observational

Primary location

Shenzhen Institutes of Advanced Technology，Chinese Academy of Sciences

Shenzhen, Guangdonng, 518055, China

Location status: Recruiting

About this study

The investigators will recruit healthy Chinese children aged 7-13 years to participate in a study investigating growth and energy needs. Each participant will complete basic anthropometric measurements-including height, weight, waist and hip circumference, and mid-upper arm circumference. Questionnaires will be used to assess family socioeconomic status, dietary intake, and pubertal development. The investigators will also measure total energy expenditure, basal metabolic rate, physical activity, body composition, and environmental temperature exposure.

This research will provide accurate data on the energy expenditure of children and adolescents living in China. These data will inform national estimates of food and energy requirements, support public health nutrition strategies, and help fill critical data gaps in the IAEA Doubly Labeled Water (DLW) database.

Study Details Anthropometric Measurements

  • 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.
  • 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.
  • 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.
  • 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.
  • Mid-Upper Arm Circumference: The participant will stand or sit upright with the arm relaxed. The midpoint between the acromion (shoulder) and olecranon (elbow) will be marked. A measuring tape will be wrapped around this midpoint with light contact. Two measurements will be taken and averaged.

Questionnaires

  • Family Socioeconomic Status: Will be assessed using a structured SES questionnaire.
  • Pubertal Development: Will be assessed via Tanner staging for secondary sexual characteristics.
  • Dietary Intake: Will be assessed using three 24-hour dietary recall questionnaires administered on non-consecutive days.

Body Composition (BIA) Bioelectrical impedance analysis (TANITA MC-780) will be used to measure segmental weight (arms, legs, trunk), total body fat percentage (fat%), fat mass (FM), fat-free mass (FFM), total body water (TBW), muscle mass, and BMI.

Basal Metabolic Rate Basal metabolic rate (BMR) will be measured using indirect calorimetry via a Cosmed Quark system with a ventilated hood. After a 10-hour overnight fast and no strenuous activity in the preceding day, participants will lie supine under the hood for 30 minutes. Oxygen consumption and carbon dioxide production will be monitored, and the final 10 minutes will be used to calculate BMR (Weir, 1949). Equipment will be validated monthly via alcohol burn tests and turbine flow calibration.

Total Energy Expenditure (DLW Method) Total energy expenditure (TEE) will be measured using the doubly labeled water (DLW) method. Urine samples will be collected and stored at -20 °C, then shipped on dry ice to Dr. John Speakman's laboratory at the University of Aberdeen or to the Shenzhen Institute of Advanced Technology. Isotope ratios will be analyzed using a near-infrared isotope gas analyzer. Mean CO₂ production will be calculated using equations developed by Speakman et al. (2021), and TEE will be derived using the Weir equation (1949).

Environmental Temperature Exposure Environmental exposure will be monitored using iButton sensors (DS1921G). These will be placed in the participant's living environment (e.g., on a backpack, clothing, indoor wall, or building exterior) using waterproof medical-grade adhesive. This will allow measurement of ambient temperature during the study period.

Physical Activity Physical activity will be monitored using ActiGraph GT3X accelerometers worn at the waist for 14 consecutive days, except during water activities (e.g., bathing or swimming). Data will be considered valid if the monitor is worn for at least 12 hours on four days, including at least two weekdays and two weekend days. The first day of wear and any day with insufficient data will be excluded from analysis.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

-Healthy participants

Exclusion criteria

  • Malnutrient as defined by the Chinese national standards WS/T 456-2014 and WS/T 586-2018
  • Nutritional deficiencies
  • Overweight
  • Obesity
  • Acute illness within the past 7 days
  • Fever
  • Diarrhea
  • Vomiting
  • 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

Treatment and study plan

Primary outcomes

  1. Height

    Time frame: About 3 minutes.

    Height in centimetres will be measured by Leicester stadiometer(Seca 217, Germany).

  2. Weight

    Time frame: About 5 minutes.

    Weight in kilograms will be measured by TANITA.

  3. BMI

    Time frame: About 10 minutes (calculated).

    BMI values in kg/m2 were calculated from weight measured by TANITA and height measured by Leicester stadiometer (Seca 217, Germany).

  4. Fat mass

    Time frame: About 3 minutes.

    Fat mass in kilograms will be measured by TANITA.

  5. Fat percentage

    Time frame: About 3 minutes.

    Fat percentage will be measured by TANITA.

  6. Fat-free mass

    Time frame: About 3 minutes.

    Fat-free mass in kilograms will be measured by TANITA.

  7. Muscle mass

    Time frame: About 3 minutes.

    Muscle mass in kilograms will be measured by TANITA.

  8. Total body water

    Time frame: About 3 minutes.

    Total body water in kilograms will be measured by TANITA.

  9. Anthropometric measurements

    Time frame: About 10 minutes.

    Anthropometric measurements, including waist circumference (measured in centimeters), will be obtained using a flexible tape measure following standardized protocols.

  10. Anthropometric measurements

    Time frame: About 10 minutes.

    Anthropometric measurements, including hip circumference (measured in centimeters), will be obtained using a flexible tape measure following standardized protocols.

  11. Anthropometric measurements

    Time frame: About 10 minutes.

    Anthropometric measurements, including mid-upper arm circumference (measured in centimeters), will be obtained using a flexible tape measure following standardized protocols.

  12. Family socioeconomic status

    Time frame: About 5 minutes.

    Family socioeconomic status will be assessed by the Family Socioeconomic Status Questionnaire (SES).

  13. Secondary sexual characteristics

    Time frame: 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).

  14. Dietary intake

    Time frame: About 10 minutes (three times).

    The 24-hour dietary recall questionnaire is used to investigate the dietray intake level of the subjects. Three daily meals will be collected to calculate the dietary intake in kcal or MJ.

  15. Basal metabolic rate

    Time frame: About 30 minutes.

    The basal metabolic rate in kcal or MJ will be measured by respiratory indirect calorimetry (Cosmed).

  16. Total energy expenditure

    Time frame: 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.

  17. Environmental temperature

    Time frame: 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).

  18. Physical activity

    Time frame: About 14 days.

    Physical activity of the participants will be recorded using a GT3X accelerometer worn at the waist for a consecutive period of 14 days. Outcomes measured by the GT3X included physical activity energy expenditure in kcal or MJ, Total MVPA in minutes per day , and Vector Magnitude Counts expressed as counts per minute.

Study contacts

Contact information is provided by the study sponsor or research team.

Xinyue Ma, Master

CONTACT

[email protected]

19966463830

Xueying Zhang, Doctor

CONTACT

[email protected]

18201296155

Sponsors and collaborators

Lead sponsor

Shenzhen Institutes of Advanced Technology ,Chinese Academy of Sciences

Other

Registry information

Official study title

Study on Total Energy Expenditure and Its Influencing Factors in Chinese Children Aged 7-13 Years (Including Rural Areas) Using the Doubly Labelled Water Method

Important dates

Study start
2025
Primary completion
2027
Study completion
2027
First posted
Jul 8, 2025
Registry last updated
Jul 8, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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