What is the impact of consuming high fat/sugar and low fiber foods on TEF?

Consuming high fat and sugar foods while having a low fiber intake is likely to decrease the thermic effect of food (TEF). TEF refers to the increase in metabolic rate after ingestion of food, mainly due to the energy required for digestion, absorption, and metabolism. Foods that are high in sugar and fat tend to be more calorie-dense and require less energy to break down compared to foods that are rich in fiber, protein, and complex carbohydrates.

Fiber-rich foods require more energy for digestion and have a higher TEF because they engage the digestive system more significantly. When the diet consists primarily of high fat and sugar, the body does not expend as much energy for processing these foods, thus resulting in a lower overall TEF. This lower energy expenditure in digestion contributes to less efficient calorie burning, which can affect weight management and overall metabolic health. Therefore, the choice indicating that consuming high fat/sugar and low fiber foods decreases TEF is accurate, as it highlights the reduced metabolic activity associated with these food types.