It is three years this week since the launch of the Public Health Responsibility Deal. At the time, the government said its approach - working in partnership with the food industry and others to agree voluntary action - would deliver change further and faster than was possible by legislation.

“The Deal has made a difference. But has it made enough of one?”

There is no doubt that the Deal has achieved change. For example, last week saw the launch of new salt reduction targets which, if met across the food industry, could have a huge impact on public health. These build on the previous 2010 and 2012 targets, which companies are meeting to different degrees. Other pledges have included action to take transfats out of foods and to reduce levels of satfat and calories in products.

The wide-scale adoption of traffic light labelling by all the major retailers and several leading manufacturers could also be seen as a victory for the Responsibility Deal. Traffic light labels should be visible across all supermarkets in the next few months, enabling people to make far more informed choices.

The pledge on out-of-home calorie labelling was also an encouraging development, with several leading restaurant chains signing up and displaying calorie labelling on their menu boards.

So, the Deal has made a difference. The question is whether it is making enough of one. While these pledges are helping to focus attention on key actions that will make it easier for people to eat healthily, the number of companies signing up is still very variable. Some have gone much further than others on salt reduction, for example, and the new pledge has taken a long time to develop. The catering sector in particular still needs to do more.

The pledges on satfat reduction, calorie reduction and the pledge on fruit and vegetables have again had some take-up but not enough. The wording is so vague that a wide range of actions are possible, with some companies doing more than others. The pledge on transfats helped highlight the issue but most mainstream companies had already taken action prior to the Deal.

With only a third of people now a healthy weight in the UK and childhood obesity a major issue, the Responsibility Deal must do more. Public health and commercial interests will not always be aligned or deliver the pace of change required. And nothing happens to companies that fail to act - not even bad publicity.

Greater government direction is now essential to ensure there is more action on issues such as reducing sugar, fat and salt, and ensuring promotions are more responsible. If voluntary action proves inadequate, ministers must look to other measures to protect the nation’s health.

Sue Davies is chief policy adviser at Which?