Background Learning to recognize hunger and only eating when hungry is likely to be beneficial for weight loss. Other investigators have developed an intriguing way of training people to recognise their hunger by encouraging participants to only eat when blood glucose is under a specified cut-off. Despite potentially important effects on weight, no other groups appear to have replicated this method. The aim of this study was to assess the feasibility of hunger training prior to implementation into a randomised controlled trial.
Method Thirty participants underwent hunger training for 2 weeks. Feasibility criteria were decided a priori and included set criteria for study retention (≥85%), adherence to measuring blood glucose before eating (≥80% of the time), and adherence to only eating when blood glucose was below a specified cut-off (≥75% of eating occasions). We used an adaptive design that allowed testing of an individualised cut-off based on fasting blood glucose (protocol B) if the original blood glucose cut-off of 4.7 mmol/L (protocol A) proved not to be feasible.
Results Study retention was high at 97%, as was adherence to measuring blood glucose at 94%, both achieving our feasibility criteria. After 20 participants completed hunger training, protocol A was analysed. As adherence to only eating under the cut-off was only 66% and thus under our criterion of 75%, we instituted protocol B for the remaining participants, which resulted in an adherence of 84%. Participants reported an increased awareness of appetite and reduction in non-hungry eating.
Conclusion Hunger training appears to be a feasible method of training people to only eat when hungry, as long as the blood glucose cut-off used is individualised. The effectiveness of hunger training for weight loss will be examined in our 2-year RCT investigating different support strategies for long-term weight management (SWIFT).