#214 Optimal Nutrition: Fiber's Impact on Glucose and Cholesterol
Release Date: 03/05/2026
Hart2Heart with Dr. Mike Hart
In this solo episode on androgenic alopecia, the host explains that hair loss is slow and progressive, driven largely by genetics and DHT-mediated miniaturization of follicles across the anagen, catagen, and telogen cycle, and stresses early detection using periodic photos of the temples, hairline/vertex, and crown. He frames hair growth as a “battle” between Wnt signaling (promotes growth and anagen entry via stem cell activation) and DHT signaling (suppresses Wnt and increases inhibitors like DKK, TGF-beta, and PGD2), noting advanced loss involves inflammation, fibrosis, and irreversible...
info_outlineHart2Heart with Dr. Mike Hart
Dr. Allen Frances discusses how AI chatbots can provide effective support for everyday stress and mild symptoms, with tens of millions using them, but warns they can be dangerous for vulnerable groups—especially the very young, the very old, the socially isolated, and people with severe mental illness—potentially contributing to psychosis, suicide, or eating disorders. He argues harm is driven by chatbots being programmed to be pleasing and validating to maximize screen time, creating dependency and “echo chambers,” and highlights major privacy risks and manipulation potential given...
info_outlineHart2Heart with Dr. Mike Hart
In a wide-ranging interview, Dr. Sylvain Charlebois (“The Food Professor”) discusses whether lab-grown (cellular) meat is overhyped, citing consumer acceptance, cost, and labeling as key barriers, though he found lab-grown chicken indistinguishable in taste and notes potential for nutrient customization. The conversation then turns to Canadian food inflation, arguing there is little evidence grocers are gouging consumers via higher margins, though grocers pressure suppliers through fees, affecting prices and supply-chain discipline. Charlebois contends food inflation is largely structural...
info_outlineHart2Heart with Dr. Mike Hart
Dr. Mike Hart interviews Dr. Russell Kennedy about chronic anxiety as a childhood safety adaptation that never turns off, driven more by a body-based “alarm” than by thinking. Kennedy explains why understanding anxiety and talk-based cognitive approaches often have limited effect because subcortical systems communicate through feeling; alarm sensations trigger the mind to generate worries, which can become dopamine-reinforced and addictive. He discusses sensitivity (often cited as 15–20% of the population), modern stressors like smartphones and social media reducing discomfort tolerance,...
info_outlineHart2Heart with Dr. Mike Hart
Dr. Mike Hart interviews elite runner Brady Holmer about endurance training, VO2 max physiology, and common misconceptions. Holmer explains that zone 2 builds the aerobic base and enables high training volume with less fatigue, notes heart-rate zones are ideally defined by lactate thresholds, and says he primarily uses perceived exertion rather than lactate or heart rate during training. He advises against guiding workouts by wearable HRV scores, arguing accurate HRV requires standardized morning measurements and that wearable data can create a nocebo effect; trends may be informative, but...
info_outlineHart2Heart with Dr. Mike Hart
Dr. Tommy Wood discusses evidence that stimulants can help people with ADHD but may worsen complex cognitive performance in non-ADHD users despite feeling more focused. He outlines an ideal brain-health day centered on consistent sleep opportunity, morning caffeine timed to protect sleep, nutrient-dense meals (protein, B vitamins, omega-3s, fiber, antioxidants), frequent movement to break up sedentary time, and structured exercise including cardio, resistance training, HIIT (notably Norwegian 4x4), and open-skill sports for added cognitive benefits. He emphasizes bright morning light and...
info_outlineHart2Heart with Dr. Mike Hart
The script explains why fiber is critical for gut and metabolic health, focusing on how soluble fiber is fermented in the colon to produce short-chain fatty acids (butyrate, propionate, acetate). It contrasts soluble fiber (forms a gel, lowers LDL by binding bile acids, slows glucose absorption, increases satiety, feeds the microbiome) with insoluble fiber (adds stool bulk, helps constipation). It highlights research showing 10 g/day psyllium husk (Metamucil) is linked to a 10% reduction in all-cause mortality and typically lowers LDL about 7–15%. Butyrate is emphasized as the primary fuel...
info_outlineHart2Heart with Dr. Mike Hart
Dr. Roger McFillin argues that Western allopathic medicine and psychiatry have medicalized normal human suffering by reducing emotions to biological or chemical reactions, turning symptom checklists into fixed identities, and sustaining a drug-driven “sick care” system that creates lifelong customers. He contrasts this with viewing emotions as powerful energy meant to be moved into creation and transformation, cites psychoneuroimmunology, and warns that suppressing fear and distress with pharmaceuticals can worsen long-term outcomes. The conversation covers exposure-based approaches to...
info_outlineHart2Heart with Dr. Mike Hart
This episode explores tadalafil (Cialis) as a potential longevity drug, though no randomized human trials prove it extends lifespan. Cialis works by blocking PDE5, enhancing nitric oxide signaling, and improving blood flow through vasodilation. Originally approved for pulmonary hypertension, it's also used for erectile dysfunction and BPH. Its 36-hour half-life makes it superior to Viagra for continuous longevity effects. The host frames vascular aging and endothelial dysfunction as key drivers of age-related diseases (heart disease, stroke, dementia, kidney disease). Observational data...
info_outlineHart2Heart with Dr. Mike Hart
In this podcast episode, an in-depth discussion is provided on the drug Telmisartan, commonly used for lowering blood pressure. The host elaborates on how it belongs to a class of medications known as angiotensin receptor blockers (ARBs) and stands out due to its 24-hour half-life and partial PPAR-gamma agonist activity. The episode explores Telmisartan's potential benefits for longevity, including its properties that reduce cardiovascular mortality, renal decline, and metabolic issues. It also compares Telmisartan with other ARBs and addresses its unique ability to improve myocardial...
info_outlineThe script explains why fiber is critical for gut and metabolic health, focusing on how soluble fiber is fermented in the colon to produce short-chain fatty acids (butyrate, propionate, acetate). It contrasts soluble fiber (forms a gel, lowers LDL by binding bile acids, slows glucose absorption, increases satiety, feeds the microbiome) with insoluble fiber (adds stool bulk, helps constipation). It highlights research showing 10 g/day psyllium husk (Metamucil) is linked to a 10% reduction in all-cause mortality and typically lowers LDL about 7–15%. Butyrate is emphasized as the primary fuel for colonocytes, supporting gut barrier integrity and potentially reducing colon cancer risk, while also affecting mitochondria, inflammation, and the brain. Propionate influences liver cholesterol production and satiety hormones, and acetate provides systemic energy. Practical supplementation “stacks,” dosing ranges, food sources, GI side effects, and timing cautions (e.g., separating psyllium from minerals) are discussed.
Metamucil (psyllium husk fiber) — https://www.metamucil.com/
Psyllium husk (soluble fiber) — https://medlineplus.gov/druginfo/meds/a601104.html
Psyllium husk (PubMed search) — https://pubmed.ncbi.nlm.nih.gov/?term=psyllium+husk
Soluble fiber (overview) — https://medlineplus.gov/dietaryfiber.html
Insoluble fiber (overview) — https://medlineplus.gov/dietaryfiber.html
Inulin (prebiotic fiber) — https://pubmed.ncbi.nlm.nih.gov/?term=inulin+prebiotic+fiber
Acacia fiber / Gum arabic (prebiotic fiber) — https://pubmed.ncbi.nlm.nih.gov/?term=acacia+fiber+gum+arabic+prebiotic
Beta-glucan (oats/barley soluble fiber) — https://pubmed.ncbi.nlm.nih.gov/?term=beta-glucan+oats+LDL
Pectin (soluble fiber) — https://pubmed.ncbi.nlm.nih.gov/?term=pectin+soluble+fiber
Partially hydrolyzed guar gum (PHGG) — https://pubmed.ncbi.nlm.nih.gov/?term=partially+hydrolyzed+guar+gum
Resistant starch / Potato starch — https://pubmed.ncbi.nlm.nih.gov/?term=resistant+starch+potato+starch
Short-chain fatty acids (SCFAs) — https://www.ncbi.nlm.nih.gov/books/NBK557571/
Butyrate (SCFA) — https://pubmed.ncbi.nlm.nih.gov/?term=butyrate+short-chain+fatty+acid+colonocytes
LDL cholesterol (general) — https://medlineplus.gov/cholesterol.html
Magnesium (mineral supplement info) — https://medlineplus.gov/magnesium.html
Show Notes
00:00 Butyrate and Colon Health
00:49 Why Fiber Matters Now
02:28 How Fiber Is Digested
03:45 Soluble vs Insoluble Fiber
06:36 Gel Effect on Blood Sugar
07:36 How Soluble Fiber Lowers LDL
10:19 Short Chain Fatty Acids 101
11:32 Butyrate Deep Dive
16:40 Propionate and Liver Benefits
18:22 Acetate for Energy and Appetite
19:29 Best Fibers to Supplement
21:33 Dosing and Food Sources
24:44 Ideal Fiber Stack and Safety
28:37 Wrap Up and Next Steps
The Hart2Heart podcast is hosted by family physician Dr. Michael Hart, who is dedicated to cutting through the noise and uncovering the most effective strategies for optimizing health, longevity, and peak performance.
This podcast dives deep into evidence-based approaches to hormone balance, peptides, sleep optimization, nutrition, psychedelics, supplements, exercise protocols, leveraging sunlight, and de-prescribing pharmaceuticals — using medications only when absolutely necessary.
Beyond health science, we explore the intersection of public health and politics, exposing how policy decisions shape our health landscape and what actionable steps people can take to reclaim control over their well-being.
Guests range from out-of-the-box thinking physicians such as Dr. Casey Means (author of "Good Energy") and Dr. Roger Sehult (Medcram lectures) to public health experts such as Dr. Jay Bhattacharya (Director of the National Institutes of Health (NIH) and Dr. Marty Mckary
(Commissioner of the Food and Drug Administration (FDA) and high-profile names such as
Zuby and Mark Sisson (Primal Blueprint and Primal Kitchen).
If you’re ready to take control of your health and performance, this podcast is for you.We cut through the jargon and deliver practical, no-BS advice that you can implement in your daily life, empowering you to make positive changes for your well-being.
Connect with Dr. Mike Hart
Instagram: @drmikehart
Twitter: @drmikehart
Facebook: @drmikehart