June 29, 2026
Episode #9: Fiber
Jason and Brian kick off this episode with their Hot Topic: Fibermaxxing, breaking down why fiber is getting so much attention and why “fiber maxing” has become a major wellness trend. They cover what fiber actually is, the difference between soluble and insoluble fiber, and why this essential carbohydrate does far more than support regularity. The focus is simple — most of us are not getting enough fiber, and adding it back the right way can support digestion, appetite, blood sugar balance, gut health, and overall wellness.
🔥 Rapid Fire: Buy or Don’t Buy – A practical round on the best food sources and supplements for fiber. Jason and Brian cover legumes, flax, chia, fruits with skin, oats, quinoa, brown rice, barley, sweet potatoes, broccoli, psyllium husk, acacia fiber, inulin, chicory, resistant starches, and conventional fiber supplements — breaking down what works, what to watch for, and why whole foods should come first.
🌿 Mind and Body Connection – The episode closes with a conversation about vagus nerve stimulation, stress, sleep, anxiety, digestion, and the gut-brain connection. From wearable devices to the way stress affects the body, Jason and Brian explore how the nervous system and gut communicate, and why calming that system may support better sleep, mood, and overall balance. Grounded in decades of experience, this episode takes a fresh look at fiber as one of the most overlooked tools in modern health — from gut support and weight management to muscle strength, cravings, and feeling better from the inside out.
00:00:00 Introduction
00:03:21 Hot Topic: Fibermaxxing
00:37:50 Rapid Fire: Buy or Don’t Buy
00:45:35 Mind and Spirit – Mental Health
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#fiber #fibermaxxing #solublefiber #vagusnerve #légumes #flaxseed #chiaseeds #oats #quinoa #brownrice #barley #sweetpotato #broccoli #psylliumhusk #acacia #inulin #chicory #resistantstarches
References
[0:00] Fiber and Building Muscle
Fiber can help build muscle, suppress appetite, and aid weight management (episode thesis).
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[4:14] Fiber is Indigestible
Fiber is the indigestible part of plants; the part the body does not truly digest.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[4:31] Fiber is a Carbohydrate
Fiber is a carbohydrate by structure.
Reference: Dietary fibre in foods[4:44] Fiber & Blood-Sugar
Unlike simple/refined carbs, fiber does not drive blood-sugar and insulin spikes; it works the opposite way.
Reference: Dietary Fiber, Atherosclerosis, and Cardiovascular Disease[5:02] Fiber is an 'Essential Carbohydrate'
Fiber is an ‘essential carbohydrate’ – the body cannot make it, so it must come from outside.
Reference: Dietary Reference Intakes Proposed Definition of Dietary Fiber.[5:22] Fiber & Improving Health
Add back fiber and you can improve your health ‘overnight, literally.’
Reference: Rhetorical - no specific study[6:25] Two Forms of Fiber
There are two basic forms of fiber: soluble and insoluble.
Reference: Physicochemical and Functional Properties of Soluble and Insoluble Dietary Fibers in Whole Grains and Their Health Benefits[6:40] About Soluble Fiber
Soluble fiber includes pectins, gums, mucilage, inulin, and resistant starches; it dissolves in water and forms a gel.
Reference: Dietary fiber[6:58] Gel from Soluble Fiber
The gel from soluble fiber slows gastric emptying time.
Reference: Dietary Fiber, Atherosclerosis, and Cardiovascular Disease[7:32] Gastic Empyting
Because it slows gastric emptying, fiber helps you feel fuller longer.
Reference: Short-Term Effect of Additional Daily Dietary Fibre Intake on Appetite, Satiety, Gastrointestinal Comfort, Acceptability, and Feasibility[7:56] Introducing Fiber
Introducing a lot of fiber all at once can cause gas and bloating.
Reference: Beat the bloat — 4 tips for increasing your fiber intake[8:08] Increasing Fiber
Increase ~3 to 5 g/day over a 2 to 4 week period to reach a target of 25 to 30 g/day; don’t jump straight to 25-30.
Reference: Chart of high-fiber foods[8:28] Fiber Stopping Insulin Spikes
Fiber delays glucose/sugar absorption into the blood, helping stop sugar and insulin spikes.
Reference: Dietary Fiber, Atherosclerosis, and Cardiovascular Disease[8:45] Orange Juice
Orange juice is a ‘sugar bomb’ that spikes blood sugar; eating the whole orange with its pectins slows sugar absorption.
Reference: Dietary Fiber, Atherosclerosis, and Cardiovascular Disease[9:12] Juicing
Juicing (extracting juice) removes the fiber/pectins; blending into a smoothie keeps them.
Reference: Dietary fiber[10:22] Soluble Fiber & Prebiotics
Soluble fiber acts as a prebiotic, feeding the good gut bacteria, which ferment it.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[10:53] Bacterial Fermentation
Bacterial fermentation of fiber produces short-chain fatty acids (postbiotics) – butyrate, acetate, propionate.
Reference: Butyrate and Gut Health: Why Short-Chain Fatty Acids Matter[11:07] SCFAs & Absorption
SCFAs increase nutrient absorption, decrease inflammation, and support immune and metabolic function (incl. blood sugar control).
Reference: Short Chain Fatty Acids (SCFAs)-Mediated Gut Epithelial and Immune Regulation and Its Relevance for Inflammatory Bowel Diseases[11:26] SCFAs & Cardiovascular Health
SCFAs/soluble fiber support cardiovascular health by reducing reabsorption of ‘bad’ cholesterol.
Reference: Dietary Fiber, Atherosclerosis, and Cardiovascular Disease[12:31] Medications & Gut Microbiome
Medications – antibiotics, birth control, statins, antidepressants – disrupt or negatively interact with the gut microbiome.
Reference: Non-Antibiotic Drugs Also Disrupt the Microbiome[13:32] Info on Insoluble Fiber
Insoluble fiber (lignins, cellulose, hemicellulose) adds bulk and speeds transit – best for constipation; soluble fiber slows things and helps diarrhea.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[14:38] Gen Z & Alcohol
Callback: ‘Gen Z is consuming 85% less alcohol than previous generations.’
Reference:[16:13] Refined Sugar
Refined sugar ‘hijacks’ the metabolic system and gives a dopamine hit, so you get ‘addicted to the food.’
Reference:[18:42] Hippocrates
The father of medicine, Hippocrates, said ‘Let food be thy medicine.’
Reference: Let not thy food be confused with thy medicine[19:31] Scurvy
Irish sailors who ate citrus (specifically limes) avoided scurvy and were nicknamed ‘limey’; researchers later isolated vitamin C as the active compound.
Reference: Lind Discovers a Cure for Scurvy[21:08] Vitamin C
Vitamin C works better with bioflavonoids (and rutin); the deeper point – just eat the whole lime/fruit.
Reference: The Bioavailability of Different Forms of Vitamin C[22:45] Oats
Oats are a top soluble-fiber source, but avoid quick/instant oats because they metabolize faster and can spike blood sugar.
Reference: Steel-Cut vs Rolled vs Instant Oats[24:13] SCFAs & Intenstinal Lining
SCFAs strengthen the intestinal lining via tight junctions; weak fiber intake plus imbalance leads to ‘leaky gut.’
Reference: Acute Effects of Butyrate on Induced Hyperpermeability and Tight Junction Protein Expression in Human Colonic Tissues[25:42] Leaky Gut
Leaky gut can drive autoimmune responses and conditions like Crohn’s and colitis.
Reference: Short Chain Fatty Acids (SCFAs)-Mediated Gut Epithelial and Immune Regulation and Its Relevance for Inflammatory Bowel Diseases[26:15]
These compounds boost bacterial diversity, reduce inflammation, improve digestion, and improve nutrient absorption.
Reference: How to Increase Butyrate & SCFAs in Your Gut Naturally[27:12] Gut Muscle Axis
Research on adults over 40 (published via NIH) shows a gut-muscle axis: higher fiber linked to increased lean mass, greater skeletal-muscle strength, lower age-related muscle decline, and better grip strength.
Reference: Higher dietary fibre intake is associated with increased skeletal muscle mass and strength in adults aged 40 years and older[28:42] Fiber & Normal Levels
It was not excessive fiber – just adding fiber back to normal levels – and ‘you could actually grow more muscle’ by eating better.
Reference: Physical activity and fiber intake beneficial for muscle mass and strength preservation during aging[29:02] Fiber & Metabolic Health
Fiber improves metabolic health by slowing blood-sugar and insulin spikes, so downstream metabolic functions work better.
Reference: Dietary Fiber, Atherosclerosis, and Cardiovascular Disease[29:11] Fiber & Fat
Fiber slows, if not stops, the accumulation of fat in the muscle.
Reference: Higher dietary fibre intake is associated with increased skeletal muscle mass and strength in adults aged 40 years and older[29:37] Fiber & Appetites
Fiber supports healthy appetite, curbs cravings, and ‘turns down the food noise’ naturally, like GLP-1 drugs.
Reference: Short-Term Effect of Additional Daily Dietary Fibre Intake on Appetite, Satiety, Gastrointestinal Comfort, Acceptability, and Feasibility[29:54] Fiber & Body Fat
Fiber lowers overall body fat mass.
Reference: Higher dietary fibre intake is associated with increased skeletal muscle mass and strength in adults aged 40 years and older[29:54] SCFAs & Fiber
SCFAs from fiber help you keep the muscle you have and aid muscle protein synthesis.
Reference: Impact of a Whole-Food, High-Soluble Fiber Diet on the Gut–Muscle Axis in Aged Mice[30:32] Fiber & HMB
HMB is a great tool; fiber works indirectly and HMB directly, so the two together are an ‘unbelievable combination.’
Reference: Health Benefits of β-Hydroxy-β-Methylbutyrate (HMB) Supplementation in Addition to Physical Exercise in Older Adults[31:03] Fiber & Caloric Balance
Fiber promotes calorie balance and stops overeating by increasing fullness, slowing digestion, and improving nutrient absorption.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[31:34] Fiber & Caloric Intake
Fiber reduces both caloric intake and caloric absorption.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[32:09] Sugar Spikes
Sugar spikes, insulin resistance and diabetes are pervasive, and that is essentially what led to the GLP-1 craze.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[35:42] Adding More Fiber
Adding fiber requires drinking more water; soluble fiber absorbs water, so without enough fluid you can get constipated.
Reference: How to Get 25 Grams of Fiber Daily Without Bloating[38:21] Legumes & Fiber
Legumes (black, pinto, kidney beans) are primarily soluble fiber and an excellent source.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[38:34] Flax, Chia Seeds & Fiber
Flax and chia are high in soluble fiber; almonds/walnuts high in insoluble; mill flax and chia or they pass through unused.
Reference: Dietary fiber[38:51] Fruits & Fiber
Fruits with the skin give more soluble fiber; apples, avocados, bananas are good picks.
Reference: The Role of Dietary Fiber in Health Promotion and Disease Prevention[39:22] Oats & Fiber
Oats have about 4 to 5 g of fiber per serving.
Reference: Steel-Cut, Rolled, and Quick Oats[39:28] Quinoa & Fiber
Quinoa has about 5 g of fiber per cup and is naturally gluten-free.
Reference: Quinoa vs. Brown Rice: Which Food Has More Nutritional Value?[39:44] Brown Rice & Fiber
Brown rice has about 3 to 3.5 g of fiber per serving, is gluten-free, and is less than quinoa.
Reference: Quinoa vs. Brown Rice: Which Food Has More Nutritional Value?[39:56] Barley & Fiber
Barley is the fiber champion with 32 g of fiber per cup – about 6x brown rice – but contains gluten.
Reference: Barley, pearled, raw[40:24] Best Fiber Veggies
Best fiber veggies: sweet potato (soluble) and broccoli (insoluble).
Reference: Physicochemical and Functional Properties of Soluble and Insoluble Dietary Fibers in Whole Grains and Their Health Benefits[41:04] Psyllium Husk
Psyllium husk is a soluble fiber used mainly for bowel regularity.
Reference: Acacia Fiber Is Soluble but Non-Viscous[41:24] Acacia Fiber
Acacia fiber is preferred over psyllium because it ferments more slowly with less gas and bloating.
Reference: Gum Acacia as a Prebiotic Fiber[41:32] Inulin & Chicory
Inulin and chicory are prebiotics (the compounds are fructooligosaccharides/FOS), also found naturally in artichokes.
Reference: Acacia Fiber Is Soluble but Non-Viscous[42:07] Resistant Starches
Resistant starch is not technically fiber but acts like it; raw potato has type-2 RS, and cooking destroys it.
Reference: Resistant starch and the gut microbiome[42:40] OTC Fiber Supplements
OTC fiber supplements: Metamucil is psyllium, Citrucel is a synthetic methylcellulose, Benefiber is wheat dextrin.
Reference: Dietary fiber[43:41] Identifying Organic Foods
A 5-digit PLU starting with 9 means certified organic; 4-digit codes (3s and 4s) are non-organic.
Reference: What do PLU codes say about your produce?[43:48] Buying Organic
You should always buy organic; conventional produce carries pesticides/chemicals and GMOs that organic avoids.
Reference: The truth behind PLU stickers on produce[45:53] Vagus Nerve Stimulation
Vagus nerve stimulation has been around a while; surgical implanted versions use mild electrical current for epilepsy and neurological disorders.
Reference: Critical Review of Transcutaneous Vagus Nerve Stimulation[46:48] Vagus Nerve Wearables
The tech industry adapted that surgical knowledge into non-invasive wearables (neck band or ear).
Reference: Non-invasive vagus nerve stimulation devices[47:17] About the Vagus Nerve
The vagus nerve runs from the base of the brain through the digestive system, affects every organ system, and is the channel for the gut-brain connection.
Reference: Non-invasive vagus nerve stimulation devices[47:46] Vagus Nerve Devices
These devices run about $200-300, and people report incredible, immediate results.
Reference: The 6 Best Vagus Nerve Stimulation Devices on the Market in 2026[48:09] Heart Arrhythmias
People with heart arrhythmias or afib should consult their cardiologist before using a VNS device or a TENS unit.
Reference: The 6 Best Vagus Nerve Stimulation Devices on the Market in 2026[48:56] Info on Vagus Nerve Devices
Smart versions detect stress or poor sleep, auto-stimulate, and even track your sleep.
Reference: We Tested Vagus Nerve Stimulation Devices for Stress Relief[49:21] Vagus Nerve Devices & Sleep
Worn before or during sleep, these devices relax you, calm anxiety, and lead to more restful sleep.
Reference: We Tested Vagus Nerve Stimulation Devices for Stress Relief[49:47] Pulsetto and Dusq
Named devices: ‘PTO’ (Pulsetto), and a thin self-adhesive smart one called ‘Dusk’ (Dusq).
Reference: Pulsetto Claims Evaluated[52:00] Berries
Berry ranking by value: blackberry first, strawberry last; deep purple pigments (black/blueberries) carry anthocyanins, while red berries bring vitamin C.
Reference: 11 Reasons Why Berries Are Among the Healthiest Foods on Earth