Brought to you by Athletic Greens’s AG1 all-in-one nutritional supplement, House of Macadamias delicious and nutritious nuts, and Eight Sleep’s Pod Cover sleeping solution for dynamic cooling and heating. Nora D. Volkow, MD, is Director of the National Institute on Drug Abuse (NIDA) at the National Institutes of Health. NIDA is the world’s largest funder of scientific research on the health aspects of drug use and addiction. Dr. Volkow's work has been instrumental in demonstrating that drug addiction is a brain disorder. As a research psychiatrist, Dr. Volkow pioneered the use of brain imaging to investigate how substance use affects brain functions. In particular, her studies have documented how changes in the dopamine system affect the functions of brain regions involved with reward and self-control in addiction. She has also made important contributions to the neurobiology of obesity, ADHD, and aging.Please enjoy!This episode is brought to you by Eight Sleep! Eight Sleep’s Pod Cover is the easiest and fastest way to sleep at the perfect temperature. It pairs dynamic cooling and heating with biometric tracking to offer the most advanced (and user-friendly) solution on the market. Simply add the Pod Cover to your current mattress and start sleeping as cool as 55°F or as hot as 110°F. It also splits your bed in half, so your partner can choose a totally different temperature.Go to EightSleep.com/Tim and save $250 on the Eight Sleep Pod Cover. Eight Sleep currently ships within the USA, Canada, the UK, select countries in the EU, and Australia.*This episode is also brought to you by Athletic Greens. I get asked all the time, “If you could use only one supplement, what would it be?” My answer is usually AG1 by Athletic Greens, my all-in-one nutritional insurance. I recommended it in The 4-Hour Body in 2010 and did not get paid to do so. I do my best with nutrient-dense meals, of course, but AG1 further covers my bases with vitamins, minerals, and whole-food-sourced micronutrients that support gut health and the immune system. Right now, Athletic Greens is offering you their Vitamin D Liquid Formula free with your first subscription purchase—a vital nutrient for a strong immune system and strong bones. Visit AthleticGreens.com/Tim to claim this special offer today and receive the free Vitamin D Liquid Formula (and 5 free travel packs) with your first subscription purchase! That’s up to a one-year supply of Vitamin D as added value when you try their delicious and comprehensive all-in-one daily greens product.*This episode is also brought to you by House of Macadamias delicious and nutritious nuts! I love macadamia nuts and have been enjoying them often since keto expert Dr. Dominic D’Agostino recommended them on the podcast in 2015. They taste great, and with more healthy, monounsaturated fat than both olive oil and avocados, 27% fewer carbs than almonds, and more than 50% fewer carbs than cashews, they’re the perfect low-carb, keto-friendly, nutty snack. In fact, I just ate a handful of lightly white-chocolate-covered macadamias about an hour ago to keep me going through the afternoon until dinner. And I will say this: ​House of Macadamias produces the best-tasting macadamia nuts I’ve ever eaten… by far.​Now, listeners of The Tim Ferriss Show podcast can use code TIM20 to get 20% off all orders and a free box of their best-selling Namibian sea-salted macadamia nuts worth $35! If these are not the best macadamia nuts you have ever eaten, House of Macadamias will give a full 100% refund, guaranteed.*For show notes and past guests on The Tim Ferriss Show, please visit tim.blog/podcast.For deals from sponsors of The Tim Ferriss Show, please visit tim.blog/podcast-sponsorsSign up for Tim’s email newsletter (5-Bullet Friday) at tim.blog/friday.For transcripts of episodes, go to tim.blog/transcripts.Discover Tim’s books: tim.blog/books.Follow Tim:Twitter: twitter.com/tferriss Instagram: instagram.com/timferrissYouTube: youtube.com/timf