What are the factors affecting TEE?
The primary factors affecting Total Energy Expenditure (TEE) are its three core components: resting metabolic rate, the thermic effect of food, and physical activity.
According to sources like NCBI, TEE includes three core components:
Core Components of Total Energy Expenditure (TEE)
Total Energy Expenditure is the total amount of energy your body uses over a 24-hour period. It is composed of three main areas:
1. Resting Metabolic Rate (RMR) / Resting Energy Expenditure (REE)
This is the energy your body needs to maintain basic functions while at rest, such as breathing, circulation, brain function, and cell production. It accounts for the largest portion of TEE for most people. Factors influencing RMR/REE include age, sex, body size, muscle mass, genetics, and hormonal status.
2. Thermic Effect of Food (TEF) / Diet-Induced Thermogenesis (DIT)
TEF, also known as DIT, is the energy required by your body to digest, absorb, transport, and store the nutrients from the food you eat. This process uses energy, and the amount varies depending on the type of macronutrient consumed (protein has the highest TEF, followed by carbohydrates, then fats).
3. Physical Activity
This component includes the energy spent on all forms of movement, from structured exercise like running or weightlifting to non-exercise activity thermogenesis (NEAT), which includes activities like walking, standing, fidgeting, and performing daily tasks. This is often the most variable component of TEE and can range significantly based on a person's lifestyle and activity level.
In summary, TEE is the sum of these three factors:
| Component | Description | Contribution to TEE (Approximate) |
|---|---|---|
| Resting Metabolic Rate (RMR) | Energy for basic bodily functions at rest | 60-75% |
| Thermic Effect of Food (TEF) | Energy for digestion, absorption, and storage of nutrients | 10% |
| Physical Activity | Energy spent on all forms of movement and exercise | 15-30% (Highly Variable) |
Understanding these factors is crucial for managing energy balance, which affects body weight and overall health.
