Diet-induced thermogenesis (DIT), also known as the thermic effect of food (TEF) or specific dynamic action (SDA), refers to the increase in energy expenditure that occurs during the digestion, absorption, and metabolism of food. It is one of the components that make up the total energy expenditure of an individual.
We spend 5-15% of the total calories that we eat per day on processing and digesting that food.
When you consume food, your body requires energy to break down the food, absorb the nutrients, and store or utilize them for various metabolic processes. This process requires energy, and the amount of energy expended varies depending on the macronutrient composition of the food consumed.
Different macronutrients have varying effects on diet-induced thermogenesis:
- Protein has the highest thermic effect among the macronutrients. Studies have shown that approximately 20-30% of the calories from protein are expended during digestion, absorption, and metabolism. This means that if you consume 100 calories from protein, your body will use up to 20-30 calories during these processes.
- Carbohydrates have a moderate thermic effect. Research indicates that around 5-10% of the calories from carbohydrates are expended during digestion, absorption, and metabolism. So if you consume 100 calories from carbohydrates, your body will use 5-10 calories for these processes.
- Fats have the lowest thermic effect. Studies have found that only about 0-3% of the calories from fat are expended during digestion, absorption, and metabolism. This means that if you consume 100 calories from fat, your body will use 0-3 calories during these processes.
The macronutrient composition of a meal can affect the magnitude of diet-induced thermogenesis. Meals higher in protein have been shown to elicit a greater thermic effect compared to meals higher in carbohydrates or fats. Each person has a unique metabolic rate that can influence the magnitude of diet-induced thermogenesis. Factors such as age, body composition, and overall health can influence energy expenditure during digestion and metabolism.
Hormones such as insulin, glucagon, and catecholamines[1] play a role in regulating diet-induced thermogenesis. For example, insulin has been shown to increase the thermic effect of protein-rich meals. In terms of practical applications, if you’re looking to optimize your energy expenditure through diet-induced thermogenesis, increasing your protein intake can be beneficial. Protein-rich foods not only provide essential amino acids for muscle growth and repair but also require more energy to digest and metabolize.
However, it’s important to maintain a balanced and varied diet that includes all the necessary nutrients for overall health and well-being.
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Footnotes
- Insulin, glucagon, and catecholamines are hormones involved in regulating various metabolic processes in the body. Insulin, produced by the pancreas, helps lower blood glucose levels by promoting glucose uptake into cells and facilitating its storage as glycogen. Glucagon, also produced by the pancreas, acts in opposition to insulin to increase blood glucose levels by stimulating the breakdown of glycogen and promoting gluconeogenesis. Catecholamines, such as epinephrine and norepinephrine, released by the adrenal glands, play a role in the “fight or flight” response, increasing heart rate, blood pressure, and energy mobilization through glycogen breakdown and lipolysis. Additionally, they have effects on metabolism, including increased thermogenesis and metabolic rate. [Back]
Further Reading
Sources
- “Diet-induced thermogenesis” (Aug 18, 2004) https://pubmed.ncbi.nlm.nih.gov/15507147/
- Westerterp, K. R. (2004). Diet-induced thermogenesis. Nutrition & metabolism, 1(1), 5. doi: 10.1186/1743-7075-1-5
- Halton, T. L., & Hu, F. B. (2004). The effects of high protein diets on thermogenesis, satiety and weight loss: a critical review. Journal of the American College of Nutrition, 23(5), 373–385. doi: 10.1080/07315724.2004.10719381
- “Diet-induced thermogenesis” (August 18, 2004) https://nutritionandmetabolism.biomedcentral.com/articles/10.1186/1743-7075-1-5
- Devkota, S., Layman, D. K. (2010). Protein metabolic roles in treatment of obesity. Current Opinion in Clinical Nutrition and Metabolic Care, 13(4), 403-407
- Berg JM, Tymoczko JL, Gatto GJ. Biochemistry. 8th edition. New York: W H Freeman; 2015.
- Dungan KM, Braithwaite SS, Preiser JC. Stress Hyperglycemia. Lancet. 2009;373(9677):1798-1807.
- Widmaier EP, Raff H, Strang KT. Vander’s Human Physiology: The Mechanisms of Body Function. 15th edition. New York: McGraw-Hill Education; 2018.
- Goldstein DS. Adrenaline and the Inner World: An Introduction to Scientific Integrative Medicine. Baltimore: Johns Hopkins University Press; 2006.
