Analyzing dietary intake plays a central role in research that seeks to clarify the role of diet in the development of chronic disorders, such as obesity, coronary heart disease, cancer, and diabetes. In addition to its important role in research, dietary assessment also has commercial applications. As members of the general public have become more health conscious, they desire to know more about the quality of their diets and the degree to which they are adhering to dietary recommendations that have been established by government and private agencies to promote optimal health. All current dietary assessment instruments have strengths and limitations, which have been well documented. For example, food records and 24-hour dietary recalls are widely used in dietary assessment, yet have documented shortcomings, limiting their usefulness. Specific problems associated with records and recalls include the estimation of portion sizes, which can be difficult and overly burdensome for participants, and underreporting of dietary intake, which is characteristic of these methods. It has been proposed that currently available technology could be used to better capture information on current, actual food use. An example of this technology is the use of a digital phone with an embedded camera (camera phone) to record images of foods eaten on a meal-by-meal basis. Current use of camera phones to assess dietary intake is limited by the lack of methods to assess portion sizes, allowing for only a qualitative, not quantitative, assessment of dietary intake. In this proposed SBIR Phase I study, the feasibility of using camera phones, in association with close-range photogrammetry, to assess portion sizes of foods will be tested. Specifically, we propose to: 1) assess the feasibility of taking digital images of portions of individual foods with camera phones, of sufficient quality to allow for subsequent close-range photogrammetric analysis;2) assess the feasibility of determining quantitative estimates of portion sizes of individual foods through the development of algorithms and photogrammetric modeling based on camera phone digital images;and 3) assess the validity of the methods by determining quantities of unknown portion sizes of the test foods based on photogrammetric modeling and comparing these to measured volumes or weights of the foods. A secondary aim, which is integral to the successful completion of aims 1 through 3, is to establish a volume- weight database of standard servings of the test foods to be used in calculating unknown portion sizes of these foods. Results from this Phase I study will be used to develop an SBIR Phase II study, which will involve testing the methods developed in Phase I in a study involving human subjects and creation of a greatly expanded volume-weight database of foods.
Project Narrative Accurately assessing dietary intake is a critical component of research into the association between diet and disease and also has commercial applications in the general public. The camera phone, a relatively new technology that is rapidly becoming ubiquitous in American society, in association with close-range photogrammetry, may provide a means of improving dietary assessment methodology by accurately assessing portion sizes of foods.
