Insulin is almost universally considered a hormone whose primary purpose is to regulate blood glucose levels. Indeed, it does this. But is that the whole picture? When we look at what governs pancreatic insulin secretion inside the beta-cell, it’s about total energy and the versatility of the short-term energy supply, not about glucose. When we look at what insulin does to energy metabolism, it does far more than regulate blood glucose: it governs how we use energy and what we do with it.
What is insulin really doing? Find out in this episode. I can’t promise the episode is practical, but I promise it’s incredibly thought-provoking.
Listen on ITunes or Stitcher.
Click here to stream.
Right-click (control-click on the Mac) here and choose “save as” (“save link as” on Mac) to download.
Subscribe in your own reader using this RSS feed.
This episode is brought to you by Ample Meal. Ample is a meal-in-a-bottle that takes a total of two minutes to prepare, consume, and clean up. It provides a balance of fat, protein, and carbohydrate, plus all the vitamins and minerals you need in a single meal, all from a blend of natural ingredients. The protein is from whey and collagen. The fat is from coconut oil and macadamia nut oil. The carbohydrates, vitamins, and minerals come exclusively from food sources like sweet potatoes, bananas, cocoa powder, wheat and barley grass, and chlorella. I use Ample on Mondays when I have 12 hours of appointments with breaks no longer than 15 minutes. It keeps my brain going while I power through the long day, never letting food prep make me late for an appointment. Head to amplemeal.com and enter the promo code “CHRIS15” at checkout for a 15% discount off your first order.
This episode is brought to you by US Wellness Meats. I use their liverwurst as a convenient way to make a sustainable habit of eating a diversity of organ meats. They also have a milder braunschweiger and an even milder head cheese that gives you similar benefits, as well as a wide array of other meat products, all from animals raised on pasture. Head to grasslandbeef.com and enter promo code “Chris” at checkout to get a 15% discount on any order that is at least 7 pounds and is at least $75 after applying the discount but under 40 pounds (it can be 39.99 lbs, but not 40). You can use this discount code not once, but twice!
Ways You Can Use the Podcast Notes
Want transcripts? Sign up for the CMJ Masterpass with this special link to get 10% off.
How to Share This Podcast and Show It Love
Show Notes for “Is Insulin Really a Response to Blood Glucose?”
Here’s what you’ll find in this episode, and more:
00:55 Cliff Notes
12:45 Insulin is widely perceived as a response to blood glucose, yet there are a variety of reasons to see it as a response to short-term energy status and the versatility of that short-term energy.
14:48 Defining “insulin signaling.”
18:00 Dietary effects on insulin and glucagon: fat, protein, and carbohydrate.
21:45 Effects of insulin outside of energy metabolism: for example, glutathione synthesis, production and activation of thyroid hormone, protection against glycation.
28:10 Insulin signaling is directly triggered by the level of ATP in the pancreatic beta-cell.
35:10 Amplification signals in beta-cell: anaplerosis, cataplerosis, lipogenesis, and the pentose phosphate pathway.
45:30 The anatomy and physiology of macronutrient transport mean that fat and carbohydrate are delivered to the pancreatic beta-cell in very different ways, resulting from circulatory routes and the relative expression of glucose transporters and lipoprotein lipase.
01:07:15 Unique roles of glucose in specialized energetic pathways.
01:07:50 Cytosolic ATP generation depends on glucose and is important to red blood cells, astrocytes, the lens and cornea of the eye, the kidney medulla, the testes, and under conditions of high-intensity exercise, stress, hypoxia, or suffocation.
01:11:10 Only glucose can allow a tissue to borrow energy from the liver in the Cori cycle.
01:14:30 Glucose is the primary anaplerotic substrate; protein is secondary; fat has little anaplerotic pathway.
01:15:50 Only glucose can support the pentose phosphate pathway, which provides NADPH and 5-carbon sugars for DNA; RNA, all of the energy carriers in energy metabolism (NADPH, NADH, FADH2, Coenzyme A, ATP); synthesis of nucleotides, neurotransmitters, fatty acids, and cholesterol; recycling of vitamin K and folate.
Masterclass Lessons Related to “Is Insulin Really a Response to Blood Glucose?”
The Pentose Phosphate Pathway: How Glucose Supports Antioxidant Defense, Detoxification, Nutrient Recycling, and Far More | MWM 2.27 (coming soon to MWM Pro subscribers, scheduled for public release on August 9).
Insulin as a Gauge of Short-Term Energy Supply and Energetic Versatility | MWM 2.28 (coming soon to MWM Pro subscribers, scheduled for public release on August 11).
Sign Up for MWM Pro
Sign up for MWM Pro for early access to content, enhanced keyword searching, self-pacing tools, downloadable audio and transcripts with the slides inserted between the text in the order they appear in the videos, a rich array of hyperlinked further reading suggestions, and a community with a forum for each lesson.
Other Posts Podcast Episodes Related to “Is Insulin Really a Response to Blood Glucose?”
The Biochemistry of Why Insulin Doesn’t Make You Fat | Mastering Nutrition Episode 44
Paleo f(x) Grab Bag: Carbs, Sex Hormones, Type 1 Diabetes, and More | Mastering Nutrition Episode 11
Why “Glycation” Is a Bad Reason to Restrict Carbs | Mastering Nutrition Episode 6
What Is Measuring Our Hba1c REALLY Telling Us About Our Blood Glucose and Diabetes Risk? | Mastering Nutrition Episode 12
Wait a Second, Is Glycation Actually GOOD For You? | Mastering Nutrition Episode 13
Examine.Com Editorial: Sugar is the Ultimate Antioxidant and Insulin Will Make You Younger
Research and Educational Resources Related to “Is Insulin Really a Response to Blood Glucose?”
Komatsu. Glucose‐stimulated insulin secretion: A newer perspective. 2013.
Keane and Newsholme. Metabolic Regulation of Insulin Secretion. 2014
Tortora, Principles of Anatomy and Physiology: 14th Edition , 2013, pp. 906-9, 642-6. 752-4, 787-8, 801-2, 912, and 920-2.
Byers et al. Avian and Mammalian Facilitative Glucose Transporters. 2017.
Kersten. Physiological regulation of lipoprotein lipase. 2014.
Kalwat and Cobb. Mechanisms of the amplifying pathway of insulin secretion in the β cell. 2017.