Tracking one's daily caloric intake and expenditure has always been very imprecise because of the numerous factors on which it depends. Researchers at the University of Pittsburgh have been working on technology that can calculate how many calories one eats and burns in a day in a much more accurate fashion. They developed the eButton, a battery-operated device worn on the chest like a normal button.
The eButton contains many different sensors — a miniature camera, an accelerometer, a GPS, a temperature sensor, a gyroscope, a UV sensor and a compass. The camera records the type of food and the portion size that the wearer eats. The gyroscope records whether the wearer is sitting down or standing and the accelerometer records the speed at which he or she is moving. The compass gives the wearer's direction and the UV sensor records whether the wearer is indoors or outdoors. The GPS measures how far the wearer moves.
The conjunction of these sensors allows the eButton to track the number of calories that the wearer eats and burns as well as a myriad of other factors, including how long he or she spends outdoors or watching TV. It can determine what restaurants the wearer frequents and how long he or she spends eating. It can even record how the wearer interacts with other people while eating. These activities all determine the precise number of calories taken in and burned in the course of a day. They also determine the overall health of the user.
The team designed the eButton specifically to combat obesity, a growing problem in the United States that affects up to 60 percent of people and can lead to diseases such as diabetes and cancer. The eButton monitors many activities, which allows for an analysis of the wearer's overall health, not just how often he or she exercises and eats. "It provides recommendations for these people to fill the gap between what they're doing and what they should be doing," Mingui Sun, a professor of neurosurgery and electrical and computer engineering at the University of Pittsburgh, said.
The researchers examined different applications of technology today and wondered why they cant be used to evaluate peoples' lives. They envisioned true "personal computers," which keep detailed accounts of personal information and can be used to evaluate individual health.
It is difficult to evaluate the accuracy of the eButton because the type of food ingested by the wearer determines how well the technology can calculate the number of calories. Right now, the device has about 10 percent error. Sun believes that is still much better than having people rely on their memories.
Currently, participants in a pilot study on caloric intake and physical activity are wearing the eButton. Wearers can easily retrieve the results by attaching the device to a computer and transferring its files.
"The device only records data. Then it is returned to the lab and the lab analyzes the data," Sun said. The data have been coded so that they cannot be read until the results of the miniature camera have been scanned to block out human faces. This protects the privacy of participants in the study.
The eButton still requires some modifications and is not available commercially, but researchers are in the early stages of trying to get it mass-produced. The findings of the eButton were published in Eat Right, a journal produced by the American Dietetic Association.
