The Thermic Effect of Food (TEF) refers to the energy expenditure involved in the digestion, absorption, metabolism, and storage of nutrients after food intake. This process, also known as diet-induced thermogenesis, is part of total daily energy expenditure and has a significant impact on weight management and metabolic health.
Definition and relevance
TEF refers to the energy the body uses exclusively to process food. Although it is not the main component of daily energy expenditure—which also includes basal metabolism and physical activity—its influence on energy balance is significant. TEF constitutes approximately 5% to 15% of total calories ingested, which, accumulated over time, can make a difference in weight regulation.
Variations according to the type of nutrient
An essential feature of the TEF is that its magnitude varies depending on the composition of the diet:
- Proteins: They have the greatest thermic effect, as the body uses between 20% and 30% of the calories derived from them for processing. This means that high-protein diets require greater energy expenditure.
- Carbohydrates: Its TEF is moderate, ranging from 5% to 10%. Digesting carbohydrates requires less energy than digesting proteins.
- Fats: With a thermic effect of less than 3%, fats are more efficient in terms of processing, which means less energy is used for their absorption and storage.
These differences show that the type of macronutrient ingested directly influences postprandial energy expenditure. Therefore, modifying the composition of the diet can be an effective strategy for managing caloric balance and, consequently, body weight.
Other factors that modulate TEF
- Meal size and speed of intake: Consuming more calories requires more energy for digestion. A large meal can cause a more pronounced thermogenic spike than dividing the same amount of calories into several smaller portions. However, it's still important to balance the amount to avoid overall caloric excess.
- Frequency and regularity of meals:Maintaining regular intervals of at least two hours between meals has been observed to promote an optimal thermogenic response. When the intervals between meals are too short, the body may not return to its basal state, which reduces the magnitude of TEF with each meal.
- Consumption schedule:There is evidence that consuming the majority of caloric intake in the morning may lead to a higher TEF compared to doing so in the evening, possibly due to the influence of circadian rhythms on metabolism.
Conclusion
To maximize the thermic effect of food (TEF), it is best to eat larger meals, spaced widely apart, incorporating a higher amount of protein and reducing calorie intake later in the day.
However, it's important to emphasize that these measures shouldn't be applied if they cause unwanted effects, such as lack of energy or excessive hunger, which lead to consuming more calories. It's essential to remember that TEF is only an ally and, on its own, cannot generate a significant increase in daily energy expenditure. Therefore, it's essential to complement these strategies with appropriate physical activity if the goal is to achieve meaningful results..