Researchers studied 39 overweight or obese adults between 36 and 75 years old. They compared a group that practiced extended overnight fasting, meaning they ate their last meal at least three hours before sleeping, against a control group that kept their usual eating habits. The fasting group typically fasted for 13 to 16 hours each night, while the control group fasted for 11 to 13 hours.
After seven and a half weeks, the main finding was that the fasting group showed significantly better nighttime dipping of diastolic blood pressure compared to the control group. Other measurements showed lower nighttime heart rates, higher heart rate variability, lower nighttime cortisol, and lower glucose levels during a morning test. However, the study did not find a significant improvement in the Matsuda Index of insulin sensitivity.
No serious safety issues, adverse events, or discontinuations were reported during the study. While the results look promising for cardiometabolic function, the small number of participants limits what can be concluded. Readers should understand that this is an early, small trial and that larger studies are needed to confirm these benefits before changing personal health routines.