Our aim was to explore the acute effects of consuming snacks at different times on glucose excursions in patients with type 2 diabetes (T2D).

Seventeen patients with T2D [means±SD: age 67.4±9.4-years; BMI 23.5±3.1kg/m²; HbA_1c 55±6mmol/mol (7.2±1.0%)] were randomly assigned in this crossover study. Each participant wore a continuous glucose monitoring device for 4 days and consumed identical test meals on the second and third days, comprising breakfast at 0700h, lunch at 1200h and dinner at 1900h. Half the participants consumed 75kcal biscuits at 1230h (just after lunch) on the second day and at 1530h (mid-afternoon) on the third day, while the other half consumed snacks at the same times, but vice versa. Each patient's glucose parameters were compared against baseline for the 2days of snacking at different times of day.

Consuming snacks in the mid-afternoon led to significantly lower mean amplitudes of glycaemic excursions (mean±SEM: 5.19±0.48 vs. 6.90±0.69mmol/L, P<0.01; standard deviation: 1.75±0.17 vs. 2.16±0.21mmol/L, P<0.01) and incremental areas under the curve for glucose after dinner (479±76 vs. 663±104mmol/L per min, P<0.01) compared with snacking just after lunch, whereas mean glucose levels did not differ over the 2days.

These results suggest that consuming snacks well separated from lunch may be an effective way to suppress postprandial glucose levels and glycaemic excursions.