Dietary energy density refers to the amount of calories (energy) in a given weight of food. It is often measured in terms of calories per gram of food. Research in this area focuses on how the energy density of foods can impact energy intake, weight management, and overall health. Lower energy density foods, such as fruits and vegetables, are often associated with lower calorie intake and improved weight control, while higher energy density foods, like sugary snacks and processed foods, can contribute to overeating and weight gain. Understanding the role of dietary energy density can help inform dietary recommendations and interventions for promoting healthy eating habits and preventing obesity.