Back on the podcast with me this week is sleep expert, Greg Potter, PhD. Through his articles, podcasts and live talks, Greg is helping an international audience understand the critical role sleep plays in health and wellbeing. Most recently, Greg has been studying the impact of circadian rhythm disruption, including sleep duration and meal timing, on the development of common cancers.

In this interview, Greg and I discuss Alexey Guzey’s scathing critique of Matthew Walker’s book, Why We Sleep. We also talk about some of the biological processes affected by sleep restriction, including cognition, immune health, athletic performance, and appetite. Greg shares some of the ways poor sleep is associated with cancer formation, including the damaging effects of sleep restriction on DNA and metabolism.

Here’s the outline of this interview with Greg Potter:

[00:00:09] Greg's 4-part series of articles on sleep: 1. Having trouble sleeping? A primer on insomnia and how to sleep better; 2. Sleep-maintenance insomnia: how to sleep through the night; 3. Sleep-onset insomnia: how to get to sleep fast; 4. Sleep for athletes: are athletes a different breed?

[00:00:28] Greg's previous podcasts: How to Entrain Your Circadian Rhythm for Perfect Sleep and Metabolic Health; Morning Larks and Night Owls: the Biology of Chronotypes; What to Do When You Can’t Sleep; Better Sleep for Athletes.

[00:01:11] 2020 Metagenics International Congress on Natural Medicine.

[00:03:36] Book: Why We Sleep, by Matthew Walker, PhD.

[00:03:38] Article: Matthew Walker's "Why We Sleep" Is Riddled with Scientific and Factual Errors, by Alexey Guzey.

[00:04:12] Book: Thinking, Fast and Slow by Daniel Kahneman.

[00:10:23] Dimensions of sleep; Article: Buysse, Daniel J. "Sleep health: can we define it? Does it matter?." Sleep 37.1 (2014): 9-17.

[00:12:34] The transtheoretical model of behavior change.

[00:16:34] Stephan Guyenet’s Red Pen Reviews.

[00:18:40] Chronotypes and the Sentinel Hypothesis.

[00:19:39] Are people not sleeping enough?

[00:21:56] Sleep duration in the US might be increasing; Study: Basner, Mathias, and David F. Dinges. "Sleep duration in the United States 2003–2016: first signs of success in the fight against sleep deficiency?." Sleep 41.4 (2018): zsy012.

[00:26:12] People overestimate their sleep duration; Study: Lauderdale, Diane S., et al. "Self-reported and measured sleep duration: how similar are they?." Epidemiology (2008): 838-845.

[00:28:29] Insulin sensitivity and testosterone higher after extended sleep; Killick, Roo, et al. "Metabolic and hormonal effects of ‘catch‐up’sleep in men with chronic, repetitive, lifestyle‐driven sleep restriction." Clinical endocrinology 83.4 (2015): 498-507.

[00:29:00] Plasma IL-6 higher after sleep restriction; Study: Pejovic, Slobodanka, et al. "Effects of recovery sleep after one work week of mild sleep restriction on interleukin-6 and cortisol secretion and daytime sleepiness and performance." American Journal of Physiology-Endocrinology and Metabolism 305.7 (2013): E890-E896.

[00:29:25] Better cognitive function with more sleep; Study: Kazem, Yusr MI, et al. "Sleep deficiency is a modifiable risk factor for obesity and cognitive impairment and associated with elevated visfatin." Open access Macedonian journal of medical sciences 3.2 (2015): 315.

[00:29:37] Effects of sleep on appetite; Study: Al Khatib, H. K., et al. "The effects of partial sleep deprivation on energy balance: a systematic review and meta-analysis." European journal of clinical nutrition 71.5 (2017): 614-624.

[00:30:02] Sleep extension and exercise performance; Study: Mah, Cheri D., et al. "The effects of sleep extension on the athletic performance of collegiate basketball players." Sleep 34.7 (2011): 943-950.

[00:32:45] Assessing current sleep status.

[00:33:11] Podcast with Ashley Mason: How to Use Cognitive Behavioral Therapy for Insomnia.

[00:36:14] WHO (five) Well-Being Index; Short Form 12; Short Form 36.

[00:38:55] NBT’s Health Assessment Questionnaire.

[00:39:57] Sleep and all-cause mortality.

[00:46:56] Sleep restriction leads to worse performance; Van Dongen, Hans, et al. "The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation." Sleep 26.2 (2003): 117-126.

[00:47:31] Josh Turknett's 4-Quadrant Model; Podcast: How to Win at Angry Birds: The Ancestral Paradigm for a Therapeutic Revolution.

[00:48:30] Sleep duration and cancer.

[00:49:20] Short sleep duration associated with cancer among asians; long sleep duration associated with colorectal cancer; Study: Chen, Yuheng, et al. "Sleep duration and the risk of cancer: a systematic review and meta-analysis including dose–response relationship." BMC cancer 18.1 (2018): 1149.

[00:51:02] Sleep deprivation and DNA damage: Study: Cheung, V., et al. "The effect of sleep deprivation and disruption on DNA damage and health of doctors." Anaesthesia 74.4 (2019): 434-440; and Carroll, Judith E., et al. "Partial sleep deprivation activates the DNA damage response (DDR) and the senescence-associated secretory phenotype (SASP) in aged adult humans." Brain, behavior, and immunity 51 (2016): 223-229.

[00:51:16] Article: Seyfried, Thomas N., et al. "Cancer as a metabolic disease: implications for novel therapeutics." Carcinogenesis 35.3 (2014): 515-527.

[00:56:22] Matthew Walker's website.

[00:59:47] Greg’s website; Instagram, Twitter, LinkedIn.

[01:02:55] Sleepio. (SHUTi no longer available).