Effects of a healthier snack on snacking habits and glycated Hb (HbA1c): a 6-week intervention study

Dietary behaviour modification may change eating habits and reduce the impact of poor nutrition. This study aimed to evaluate the effects of daily consumption of a healthier snack bar on snacking habits and glycated Hb (HbA1c) within a 6-week intervention. In all, twenty-eight participants were randomly allocated to two groups to either consume the bars as the main snack for 6 weeks (n 14) or receipt of the bars was delayed for 6 weeks (n 14) following a stepped-wedge design. All participants had HbA1c concentrations measured at weeks -1, 0, 4, 6, 10 and 12. A short dietary habits questionnaire was self-completed at weeks 0, 6 and 12. Participants consumed the bars they received instead of other snacks, and found that the healthier snack bar was acceptable as part of their daily dietary pattern. Over the 12 weeks, there was a significant reduction in intake of biscuits, cakes and pies (approximately 2 servings/week, P<0·05) in both groups. Fruit juice intake was reduced (approximately 1 serving/week, P=0·029) in the first group. In all, twenty participants (71·4 %) experienced a decrease (n 15) or no change (n 5) in HbA1c (range 0-4 mmol/mol), whereas eight participants experienced an increase in HbA1c (range 0·5-2·5 mmol/mol). There was high compliance with the healthier snack intervention and a trend towards a favourable effect on glucose homoeostasis. Habitual snacking behaviour has the potential to be improved through changes in the food supply, and in the longer term may reduce the impact of poor nutrition on public health.