Abstract
There is increasing experimental evidence for beneficial effects of calorie restriction
and intermittent fasting in type 2 diabetes mellitus (T2DM). In humans, prolonged
fasting is established as a health-promoting complementary treatment in Europe and
claimed to improve metabolism by a complex hormetic response. We aimed to investigate
effects of a one-week fasting period compared to usual care in T2DM by means of a
pilot trial. Patients with manifest T2DM medically treated with oral hypoglycemic
agents and/or insulin were randomly assigned to a 7-day fasting program followed by
dietary advice or to usual care and dietary advice only. Fasting was performed according
to the method of Buchinger with a nutritional energy intake of 300kcal/day by liquids
only and stepwise re-introduction of solid food thereafter. Outcomes were assessed
baseline and after 4 months. Of 46 enrolled participants, 32 (n=16 each group) completed
the trial and were included for final analyses. Fasting was well accepted, there were
no serious adverse events. After 4 months mean weight decreased by 3.5 kg and 2.0 kg
in the fasting vs. control group (p=0.03) paralleled by greater reduction of abdominal
circumference (p=0.001). Fasting led to a significant decrease of systolic/diastolic
blood pressure (p=0.01; p=0.003) and increased quality-of-life (p=0.04), while for
HbA1c, insulin and HOMA-index only non-significant improvements were observed. Results
of this study suggest that prolonged fasting is feasible and might have beneficial
clinical effects. The effectiveness of fasting should be proved in larger confirmatory
trials that include intermittent fasting in follow-ups to enable more pronounced and
long-term effects.
Key words
calorie restriction - type 2 diabetes mellitus - fasting - trial