The obesity challenge to the NHS looms large. The costs of treating related health conditions, such as type 2 diabetes, are rising relentlessly. Policymakers are anxious to find answers. Prevention is the goal, but what sort of nudge is most effective to get people to look after themselves better?

A new study suggests that the fear of losing something is a better incentive than the prospect of gaining a benefit.

Health and Social Care Secretary Matt Hancock is speaking on Wednesday at a conference convened by the global insurer Vitality which will unveil new research on incentives to get healthier.

The work has not been formally peer-reviewed but the intention is to do so in preparation for publication in a medical journal. At this stage it does make interesting reading.