Mobile devices that let people track how much they eat and exercise may help them shed weight over and above the benefits of a typical weight-loss programme, according to a US study.

People who are motivated, who can couple the technology with in-person counselling and management, are going to be very successful

Researchers writing in the Archives of Internal Medicine found that overweight and obese adults lost an average of over 3.6kg more when they had personal digital assistants (PDAs) and occasional phone coaching to help them, in addition to a group programme.

There is no reason to think the same would not hold true for smartphone apps that can log nutrition and activity information, and give real time feedback, they said.

“The number-one mechanism through which people lost weight is self-monitoring, just watching what you eat and keeping a record of it,” said Goutham Rao, who wrote a commentary published with the new study.

Rao, from the NorthShore University HealthSystem in Evanston, Illinois, noted that programs for mobile devices are easily personalised, and readily available wherever people carry their phones or PDAs.

“I’m actually very optimistic that people who are motivated, who can couple the technology with in-person counselling and management, are going to be very successful,” he said.

The study included 69 overweight and obese people in their late 50s, on average, who were referred to a Veterans Affairs clinic for weight-loss support.

All were enrolled in 12 group sessions over six months, which focused on nutrition, exercise and behavioural changes to promote weight loss. Half of them were also given a PDA to record their food and activity throughout the day and had a coach who checked in with them by phone.

After six months in the trial, people in the PDA group had lost an average of almost 4.5kg and 41 per cent of them had met the goal of losing at least five per cent of their initial body weight. Those in the comparison groups had dropped just over one kilo each, on average, an 11 per cent had achieved the weight loss goal.

At the one-year mark, six months after the mobile devices were taken away, people who had used the PDAs had managed to keep off most of the weight they initially lost, said lead researcher Bonnie Spring, from the Northwestern University Feinberg School of Medicine in Chicago.

The benefits of using an app on a mobile device, Rao said, are that it can be cheaper and widely available, and can help re-engage people who are having trouble, unlike an in-person programme, with a specific end date.

Although PDAs have mostly fallen out of fashion, the researchers said smartphones can serve the same purpose as the devices used in the study. Spring said most weight-loss apps on the market have not been scientifically tested but may still help people lose weight.

Still, Rao warned, there is evidence that apps alone do not have much of an impact – and it may be more helpful to think of the technology as an aid to help from a doctor or nutritionist.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.