American Board of Surgery Qualifying Exam (ABS QE) Practice Test

What is the primary macronutrient utilized in lipogenesis?

1. Proteins

2. Fats

3. Carbohydrates

4. Vitamins

The correct answer is: Carbohydrates

The primary macronutrient utilized in lipogenesis is carbohydrates. During lipogenesis, which is the metabolic process of synthesizing fatty acids from acetyl-CoA, carbohydrates are converted into glucose through glycolysis. This glucose can then be transformed into pyruvate and subsequently, through the process of acetyl-CoA formation, leads to the production of fatty acids. Excess carbohydrates, especially in the form of sugars, stimulate insulin release, which facilitates the uptake of glucose into cells and promotes its conversion to fat. This metabolic pathway demonstrates how carbohydrates are the main contributors to the synthesis of fatty acids in the body, emphasizing their role in lipogenesis. Other macronutrients, such as fats and proteins, can also contribute to lipid metabolism, but they are not primarily utilized for the specific process of lipogenesis in the same direct way that carbohydrates are. Therefore, understanding the metabolic pathways and how carbohydrates are converted into fatty acids is crucial in the study of lipogenesis.