Specific dynamic action of food

In the body, the energy derived from food is released as body heat and also used in the synthesis of ATP. The energy captured in ATP is then transformed into other forms, i.e., chemical (synthesis of new compounds), mechanical (muscle contraction), electrical (nerve activity), electrochemical (various ion pumps), thermal (maintenance of body temperature), and informational (base sequences in nucleic acids, amino acids in proteins). In general, the energy of food provides for the specific dynamic action of food, the maintenance of the body s basal metabolism, and the energy expenditure associated with various types of activity. 

A short-term response which immediately follows the taking of food and lasts for a few hours. Its duration is related to the size and composition of the meal, and on normal diets it accounts for a 5-10% increase in the metabolic rate taken over 24 hours. This corresponds to what was previously known as the specific dynamic action of food and is greater for a diet rich in carbohydrate than for one rich in fat. 

Recent ingestion of food—Following a meal, the meta-Etolic rate rises. This increase is dependent upon the type of food eaten. CarErohydrates and fats elevate the metabolic rate 4 to 15%, whereas proteins increase the rate 30 to 60%. This phenomenon is known as the specific dynamic action of foods (SDA). 

Several hypothesis have been advanced concerning the development of increased metabolic efficiency, such as altered specific dynamic action of food, alterations of metabolism of brown fat or variations of ATP breakedown. It seems that genetic factors as well as diet in early life might play an important role for the development of obesity. 

In formulation of diets to meet energy requirements, proteins and carbohydrates are considered to yield 4 cal. per gram, and fats, 9 cal. per gram. The specific dynamic action of foodstuffs must also be considered and is usually calculated as 6 % of the total caloric value of the food over a 24-hr. period.2 ... 

HEAT INCREMENT (SPECIFIC DYNAMIC ACTION OF RECENTLY DIGESTED FOOD NET ENERGY... 

Thermic effect of food It has long been observed that eating a meal increases energy expenditure, a phenomenon also known as diet-induced thermogenesis or specific dynamic action. The increase depends on the type and quantity of food consumed. As an example, the effect of a carbohydrate-rich meal on the oxygen consumption of volunteers before and after exercise is shown in Figure 2.5. 

The energy generated by metabolism of the macronutrients is used for three energy-requiring processes that occur in the body resting metabolic rate, thermic effect of food (formerly termed specific dynamic action), and physical activity. 

In populations of fish, the flow of assimilated food can be estimated from its utilization in basal metabolism (i.e. maintaining normal functioning of cells without physical activity), active metabolism (locomotion) and specific dynamic action (energy used in digesting and absorbing food). 

Specific dynamic action (SDA) is the elevation in metabolic rate that occurs during digestion and absorption of foods. It is often ignored in calculations because its value is usually unknown and probably small (less than 10% of the total energy). 

Our DEE includes a component related to the intake of food known as diet-induced thermogenesis (DIT) or the thermic effect of food (TEE). DIT was formerly called the specific dynamic action (SDA). After the ingestion of food, our metabohc rate increases because energy is required to digest, absorb, distribute, and store nntrients. 

A minimum fasting period of 12 hours prior to measurement, so as to guarantee the absence of the specific dynamic action which accompanies food consumption. For this reason Measurement of the BMR is usually made in the morning before the subject has had breakfast... 

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