Using database values to determine food density

Estimating food weight from data on food volume requires that density of the food be known. When both volume and weight are published on food tables the density can be calculated, however for many foods volume data are not available on the food table. Using a camera image of food to document dietary intake by automatically matching the food to a database entry requires that food volume be calculated and food weight estimated. This paper discusses some considerations when using USDA food tables to calculate composition of foods documented by camera image, as well as thoughts on measuring food volume and the potential for developing default values for density using available food volume data.