Background

Intermittent fasting (IF) programs are currently studied in patients with type 2 diabetes (T2D) as potential treatment option. Besides glycemic control, an important treatment effect in T2D is change in fat distribution, for visceral fat is known to be associated with insulin resistance. However, visceral fat has not been measured by magnetic resonance imaging (MRI) in IF studies up till now. Therefore, we studied change in area of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and muscle tissue by magnetic resonance imaging (MRI) in patients with T2D using an intermittent fasting-mimicking diet (FMD).

Methods

One hundred individuals with T2D, age 18-75 years and BMI > 27 kg/m², using only metformin and/or diet alone for glycemic control, were randomized to receive twelve 5-day cycles of FMD on a monthly basis as an adjunct to usual care (n=51) or usual care only (n=49) for one year. Participants underwent MRI at baseline and after 12 months. VAT, SAT and muscle tissue were quantified as the mean area on a cross-sectional single-slice area on L3 level by automated AI.

Results

A total of 41 participants in the FMD group and 35 participants in the control group underwent MRI scans at baseline and 12 months. Intention-to-treat analyses showed a reduction in VAT in the FMD group compared to the control group (-33.4 cm², SD 55.0; vs +7.6 cm², SD 29.5; 95%CI -61.7 to -20.3; p = <0.0001). Mean SAT also reduced in the FMD group compared to the controls (-14.9 cm², SD 34.7; vs +3.2 cm², SD 22.7; 95%CI -31.8 to -4.5; p = 0.010). Mean change in muscle area was not different between the FMD group and the control group (-3.3 cm ², SD 7.9; vs -1.9 cm ², SD 6.9 cm²; 95%CI -4.9 to 1.98; p = 0.40).

Interpretation

Compared to usual care alone, the use of intermittent FMD decreases VAT and SAT, while muscle tissue was comparable between the groups. As VAT is correlated to insulin resistance, the reduction we observed in the FMD group underlines the value of using FMD in patients with T2D.