Today we return with the second half of our two-part interview with Dr. Greg Potter, a British researcher who specializes in circadian biology, sleep, diet, and metabolism. In this second part of our interview, host Ken Ford and Greg continue their conversation about circadian biology and cover topics ranging from insomnia, sleep apnea, time-restricted eating, exercise, nutrition, and supplementation. In part one of our interview, episode 136, Ken talked to Greg about how he became interested in circadian biology and the importance of synchronizing our lifestyles to be in tune with our circadian rhythms. Greg also explains why he decided to specialize in sleep and what his research has taught him about the role and importance of melatonin, a hormone that helps control the body’s sleep cycle. Dawn Kernagis was traveling during our talk with Greg and couldn’t join Ken to co-host the interview.  Greg gained attention in the U.S. and Europe for his research into the importance of biological rhythms and sleep and how they affect people’s lives. His work has been featured in the BBC World Service, the Washington Post, Reuters and other scientific journals and news outlets. In addition to being a science writer and sleep consultant, Greg also is an entrepreneur who co-founded Resilient Nutrition in 2020, a company that leverages science to produce foods and supplements geared toward helping people feel and perform better. Greg earned undergraduate and master’s degrees in exercise science from Loughborough University in England a Ph.D. from the University of Leeds. Show notes: [00:03:12] Ken opens part two of our interview with Greg by asking him about continuous positive airway pressure machines, known as CPAPs, that are used for sleep apnea and related disorders, and how these devices relate to circadian rhythms and quality of sleep. [00:05:47] Ken brings up chronotypes, the concept that some people are better suited to an earlier or later sleep schedule. Ken goes on to say that during our interview with Satchin Panda, he argued that chronotypes are largely a myth. Ken asks Greg how much he thinks chronotypes are the product of environment as opposed to evolutionary biology and genetics. [00:10:27] Ken asks what an example would be of an advanced chronotype. [00:11:54] Ken asks Greg about chrononutrition, which is the relationship between a person’s nutrition and their body clock. [00:20:46] Ken mentions that muscle protein synthesis comes up as a problem for people getting older who begin a fasting diet which is generally good for their health but prevents them from maintaining or gaining substantial muscle mass, as their protein demands are higher than they were in youth. Ken asks Greg his thoughts on a pulsatile approach to fasting and protein intake for this cohort. [00:23:39] Ken asks Greg about chronopharmacology, what it is and how it might tie into nutrition. [00:25:21] Ken asks Greg to explain his stance that we should re-engineer our lifestyles to better mimic certain aspects of our distant ancestors to protect ourselves from chronic diseases and revive the kinds of energy we had as children. Greg explains what aspects of our ancient ancestors we ought to emulate. [00:29:07] Ken mentions a paper Greg published on sleep and bodyweight, and asks Greg to expound on the relationship between sleep and weight regulation. [00:33:54] Ken asks if Greg thinks it is true that there is now an “epidemic” of sleep loss. [00:36:57] Greg gives a list of advice for people to optimize their sleep. [00:40:57] Ken mentions that many people enjoy a little wine or other drink before bed because they feel as if it helps them fall asleep. Ken asks Greg to talk about how this can damage a person’s sleep. [00:43:52] Ken asks when people should go to bed, and how much sleep is needed for a person on average, and how much variation there is in the quantity of sleep needed between people.