Researchers have developed a smartphone app as the sole method for monitoring weight loss.
The My Meal Mate app allows users to monitor their food intake and exercise, set a weight loss target and sends a weekly update on progress via text message.
The smartphone app was used on average every other day in the trial, whilst the average use of the website and paper diary was about once a week.
As a result, over the 6 months of the study those using the app lost on average 4.6kg (10lbs), compared with the 2.9kg (6.5lbs) and 1.3kg (3lbs) lost by the paper-based and online diary users, respectively.
The Department of Health has calculated the direct costs of obesity on the NHS to be 5.1 billion pounds a year and an estimated 40,000 people die annually from conditions attributable to being overweight or obese.
"Smartphone technology could be harnessed to promote health; generally people don't know how many calories they are eating daily. My Meal Mate really helped people monitor their food intake and resulted in an important amount of weight loss," Professor Janet Cade, from the School of Food Science and Nutrition, who lead the project, said.
"The labelling on food packaging can help people to identify sensible food choices but it doesn't enable them to understand the cumulative effects of the foods they eat. Keeping a food diary allows us to see where we might be eating too much and the app has proved to be the most effective tracking method by far," Professor Cade added.
Unlike other currently available smartphone apps that are aimed at helping people monitor food intake and lose weight, My Meal Mate is the first free app to contain a large UK-based food database.
This allows users to map their eating habits easily to the products they consume.
It is also the first such app to be hosted for download on the NHS Choices website.
The findings have been published in the Journal of Internet Medical Research.