A small randomized controlled clinical trial finds time-restricted eating within a 6-hour window (fasting for 18 hours) without reducing calories or losing weight improves insulin sensitivity, beta cell function, blood pressure, oxidative stress and reduces evening appetite.
All eating was supervised and approached metabolic ward rigor. The improvements in metabolism were independent of weight loss and the reduction in blood pressure was so significant that it was comparable to the standard of care blood pressure medication (ACE inhibitors).
The time-restricted eating they started early with the first meal at 8 am and dinner before 3 pm. The importance of time of day for this type of intermittent fasting is still an interesting open question, especially since there’s a lot of advocacy for late eating among 16:8 advocates, however, insulin sensitivity usually declines later in the day (and is exacerbated by the production of melatonin, which has an effect of shutting off insulin secretion). Interestingly, Dr. Satchin Panda has been gathering data via his mobile app (my circadian clock) that suggests an eating window later in the day may be comparable to an early eating window.
To learn more about time-restricted eating and intermittent fasting check out the two separate podcasts I did with Dr. Satchin Panda. The episodes have summaries, timelines, and transcripts!
Round 2 episode: https://www.foundmyfitness.com/episodes/satchin-round-2
Round 1 episode: https://www.foundmyfitness.com/episodes/satchin-panda