Energy and water metabolism in the human body under daily life conditions : An international doubly labeled water database of over 10,000 people from 40 countries
- VernacularTitle:ヒトの身体における日常生活下のエネルギーと水の代謝： 40 か国1 万人超の国際二重標識水データベース
- Author:
Yosuke YAMADA
1
Author Information
- Keywords: doubly labeled water; energy metabolism; water turnover; physical activity; environment
- From:Japanese Journal of Physical Fitness and Sports Medicine 2025;74(6):297-306
- CountryJapan
- Language:Japanese
- Abstract: This paper explains the doubly labeled water (DLW) method and introduces research findings published in Science in 2021 and 2022. The DLW method is a non-invasive technique that uses water labeled with stable isotopes, heavy oxygen (18O) and deuterium (2H), to measure total energy expenditure (TEE) and water turnover in daily life. The main features of this method are: (1) It can measure energy expenditure in daily life in a completely unrestricted state over a 1-2 week period. (2) It has accuracy that serves as a benchmark for other simplified methods. (3) It can be measured with just spot urine collection. The 2021 Science study built a database of over 6,600 people from 29 countries worldwide and analyzed total energy expenditure throughout human life. The results revealed that total energy expenditure is highest in the late teens, does not decrease during middle age (30s-50s), and shows a 0.7% annual slowdown after the 60s. Additionally, infants showed very high metabolic rates relative to their body size. The 2022 Science study measured water turnover rates in 5,604 people from 23 countries, revealing that infants lose about 25% of their body water daily, while adults lose about 10%. The study also developed a prediction equation for water turnover that considers factors such as physical activity level, body weight, gender, humidity, whether one is an athlete, human development index, altitude, age, and temperature. These studies provide important insights that contribute to solving various challenges, including establishing dietary reference intakes, preventing dehydration, developing water and food security strategies during disasters, and creating predictive models for water shortages associated with climate change.
