There’s no doubt this is a time of uncertainty. COVID-19 has changed the way most of us live, and it’s not clear when or if we’ll be able to resume the activities we took for granted just a year ago. Rather than waiting for the government to figure it all out, our best defence against infectious disease is optimising metabolic health and immune function. For that, sleep is arguably the keystone behaviour. Today I’m joined again by our resident sleep expert, Greg Potter, PhD to talk about the effects of sleep on the immune system. Greg explains how poor sleep and sleep disorders profoundly impact the body’s ability to combat infections, including the common cold, pneumonia, and COVID-19. He also discusses the importance of getting enough sleep in the days leading up to vaccination and offers pandemic-specific tips for better sleep. Here’s the outline of this interview with Greg Potter: [00:02:01] Resilient Nutrition; Long Range Fuel. [00:07:05] Changes in sleep since COVID. [00:08:50] COVID dreams. [00:11:19] Changes in sleep timing and patterns. [00:11:45] Effects of COVID-19 lockdowns on sleep and activity; Study: Blume, Christine, Marlene H. Schmidt, and Christian Cajochen. "Effects of the COVID-19 lockdown on human sleep and rest-activity rhythms." Current Biology 30.14 (2020): R795-R797. [00:12:34] Changes in sleep behaviors amongst university students; Study: Wright Jr, Kenneth P., et al. "Sleep in university students prior to and during COVID-19 stay-at-home orders." Current Biology 30.14 (2020): R797-R798. [00:13:17] Sleep disorders; insomnia. [00:13:36] Greg’s previous podcasts on entraining circadian rhythm: How to Entrain Your Circadian Rhythm for Perfect Sleep and Metabolic Health and time cues: Morning Larks and Night Owls: the Biology of Chronotypes [00:14:15] Sleep apnea. [00:15:23] Sleep apnea associated with increased mortality due to COVID-19; Study: McSharry, David, Michael T. Lam, and Atul Malhotra. "OSA as a probable risk factor for severe COVID-19." Journal of Clinical Sleep Medicine 16.9 (2020): 1649-1649. [00:16:11] Sleep apnea treatment; continuous positive airway pressure (CPAP). [00:21:13] How the immune system works. [00:24:50] TNF-alpha blockers improve sleep in rheumatoid arthritis; Detert, Jacqueline, et al. "Effects of treatment with etanercept versus methotrexate on sleep quality, fatigue and selected immune parameters in patients with active rheumatoid arthritis." Clin Exp Rheumatol 34.5 (2016): 848-856. [00:32:23] Cytokine storms. [00:33:38] Mice more susceptible to infection administered during sleep hours; Study: Lundy, Stephanie R., et al. "Effect of time of day of infection on Chlamydia infectivity and pathogenesis." Scientific reports 9.1 (2019): 1-12. [00:34:37] Better response to BCG vaccine when administered in the morning; Study: de Bree, L. Charlotte J., et al. "Circadian rhythm influences induction of trained immunity by BCG vaccination." The Journal of clinical investigation 130.10 (2020): 5603-5617. [00:35:19] Different dimensions of sleep: SATED - satisfaction, alertness, timing, efficiency, duration. [00:37:58] Associations between sleep and chronic disease. [00:39:20] People who report short sleep are at higher risk of metabolic syndrome; Meta analyses: 1. Xi, Bo, et al. "Short sleep duration predicts risk of metabolic syndrome: a systematic review and meta-analysis." Sleep medicine reviews 18.4 (2014): 293-297; 2. Iftikhar, Imran H., et al. "Sleep duration and metabolic syndrome. An updated dose–risk metaanalysis." Annals of the American Thoracic Society 12.9 (2015): 1364-1372; 3. Lian, Ying, et al. "Association between sleep quality and metabolic syndrome: A systematic review and meta-analysis." Psychiatry research 274 (2019): 66-74. [00:40:02] Sleep disturbance as a risk factor for type-2 diabetes; Meta analysis: Wang, Fei, et al. "Sleep duration and patterns in Chinese patients with diabetes: A meta‐analysis of comparative studies and epidemiological surveys." Perspectives