What is calorie/energy density?
It is simply the number of calories/energies in a given amount/volume of food.
So how it is calculated.
Take the number of calories(kcal) divided by the weight(g) of the food.
Calorie density are influenced by the composition of the food. Therefore, choosing food that are less dense in calories helps to aid weight loss. As you get to feel full by eating more volume at a lower calorie count. When you feel full your body produces leptin hormones which supresses food intake, thereby helping you stave off hunger.
Low calorie density foods are usually foods that are high in fibre or high in water content such as fruits and vegetable. High density food on the other hand usually contains lower water content and also high in fat content. E.g. biscuits, cheese and peanuts just to name a few. (processed foods are higher in calories)
A study done by Ledikwe found that people who have a low-calorie dense diet consume more volume than people with high calorie dense diet. However, the amount of calories intake is much lower. Few other studies (CucoG et al. and Stookey et al.) also showed that low calorie density diets allow for people to reduce their calorie intake without decreasing the amount of food they consume. This has been found to be one of the effective methods in facilitating weight loss.
Ledikwe JH, Blanck HM, Kettel Khan L, et al. Dietary energy density is associated with energy intake and weight status in US adults. Am J Clin Nutr 2006;83:1362-8.
Cuco G, Arija V, Marti-Henneberg C, Fernandez-Ballart J. Food and nutritional profile of high energy density consumers in an adult Mediterranean population. European Journal of Clinical Nutrition 2001;55:192-9.
Stookey JD. Energy density, energy intake and weight status in a large free-living sample of Chinese adults: exploring the underlying roles of fat, protein, carbohydrate, fiber and water intakes. European Journal of Clinical Nutrition 2001;55:349-359.