Podcast Summary: Habits and Hustle — Episode 493

Guest: Ben Greenfield
Host: Jennifer Cohen
Title: How to Actually Look 20 Years Younger + His Most Extreme Biohacks Revealed
Date: October 14, 2025

Overview

This rich, fast-paced episode features health and performance expert Ben Greenfield, who returns to the show to discuss his latest biohacks for longevity, brain and body optimization, and some of the most extreme health experiments he’s undertaken. The conversation covers practical routines, cutting-edge supplements, dietary strategies, exercise science, the role of psychedelics, the use of GLP-1 agonists, and spiritual perspectives on healing and fulfillment. Ben’s distinctive mix of scientific rigor and personal experimentation offers both actionable tips and thought-provoking, sometimes controversial, insights.

Key Discussion Points & Insights

1. Adaptogens, Brain Health, and Memory

• Performance Shots & Adaptogens (00:07–01:30)

  • Ben and Jen open by sampling a performance shot, segueing to adaptogens’ role in balancing the nervous system. Ben explains adaptogens are safer at night than CNS stimulants like caffeine.

• Ben’s Knowledge Retention (01:30–03:00)

  • Ben invokes Sherlock Holmes, describing his method for knowledge retention—writing things down to clear mental clutter.

• Optimizing Brain Health (03:00–05:00)

  • Distinguishes between simply “stimulating” the brain (with caffeine etc.) and actually providing the building blocks for neuron growth and neuroplasticity.
  • Emphasizes the physiological importance of fats like oleic acid (olive oil, Mediterranean diet) and DHA (fish oil) for myelin sheath formation—vital for cognitive function.

"If you step back and you look at brain health in general, beyond just like taking things that make you feel more awake, you need to do things that provide fuel for the brain." – Ben Greenfield (03:20)

• Importance of Protein & B Vitamins (05:00–06:55)
  • Older adults should supplement with digestive enzymes to maximize protein bioavailability, supporting muscle and neurotransmitter synthesis.
  • Plant-based diets can be suboptimal for brain health due to lower levels of key nutrients.

2. Digestive Enzymes & Glucose Control

• Enzymes for Better Digestion and Bloating (06:43–09:21)
  • Digestive enzyme supplementation helps older adults improve nutrient absorption and reduce bloating.
  • Enzyme types: proteases (protein), amylases (carbs), lipases (fats).

“As you age, as pancreatic enzyme production just decreases with age, it’s a good idea to take digestive enzymes.” – Ben Greenfield (06:55)

• Meal Timing for Enzymes (08:42–09:02)

  • Ideally take enzymes before meals; after is still beneficial.

• Carb Digestion & Blood Sugar (10:01–10:46)

  • Enzymes are most critical with protein-rich meals; for carbs, their effect can spike glucose, but pairing with blood sugar-stabilizing supplements (GDAs) helps.

• Bitter Compounds & Glucose Disposal Agents (GDAs) (10:46–15:45)

  • Natural GDAs like berberine, dihydroberberine (potent but can cause GI upset), bitter melon, and apple cider vinegar help shuttle glucose into cells, supporting blood sugar control. Bitters before meals (even just from a bar) can be a practical hack.

"If you go to a restaurant or anywhere that has a bar, they always typically have a lineup of bitters... anything bitter is a glucose disposal agent." – Ben Greenfield (12:13)

• Exercise as a Blood Sugar Regulator (15:45–16:24)

  • No supplement is as powerful as lifting weights for both acute and chronic glucose control.

• Cold Exposure for Glucose Management (16:25–17:17)

  • Cold plunging can stabilize glucose for hours.

3. Cold Plunges: Mechanisms, Myths, and Gender Differences

• Benefits and Sex Differences (17:17–20:38)
  • Women are more sensitive to cold (lower muscle mass, hormone fluctuations).
  • Studies show cold exposure is metabolically beneficial to women; initial cortisol spikes give way to long-term stress resilience.
  • Recommendation: women, especially in the luteal phase, do slightly less cold and/or for less time.

"Metabolically, cold appears to be pretty good for women for things like fat burning, sugar stabilization, et cetera." – Ben Greenfield (18:32)

• Effect on Exercise Adaptation (20:40–23:10)
  • Cold exposure immediately after tough workouts can blunt gains if done for too long. Ben’s sweet spot is 2–3 minutes at 33°F, especially BEFORE workouts for an adrenaline rush.

4. Heat, Sauna, and Exercise—What Really Works?

• Sauna Use Before vs. After Exercise (23:21–26:16)
  • Post-workout sauna provides more robust performance gains (heat shock proteins, blood cell production) than pre-workout.
  • Overly hot environments can undermine strength and power—keep the gym around 65–70°F for optimal growth.

"If your goal is just pure cardiovascular benefits, then working out in a hot environment might be superior. But if your goal is strength, power... then not so much." – Ben Greenfield (25:10)

5. Fat Loss & Exercise: Myths and Methods

• Concurrent Training Over Cardio or Strength Alone (30:19–33:41)
  • Data shows mixing strength and cardio (concurrent training) in the same workout or week yields optimal fat loss.

"The most superior form for fat loss versus just strength or just cardio is concurrent training." – Ben Greenfield (30:19)

• Zone 2 Cardio—Overhyped? (33:41–35:43)

  • While low-intensity ‘fat-burning’ cardio uses more fat as fuel, the caloric burn is low; higher-intensity, multi-modal training yields greater overall fat loss.

• Warning Signs of Overtraining & Hormonal Imbalance (38:48–42:50)

  • Watch for: elevated resting heart rate and temperature for several days, sleep disturbances (tired but wired), swelling, and lack of appetite. If ignored, chronic issues might cause slow metabolism, coldness, and low energy.

6. Nutrition: Simplifying Diet, Supplement, and Artificial Sweetener Confusion

• Focus on Calorie Control over Food Hysteria (43:06–45:05)
  • Priority for weight loss should be on calorie balance and exercise rather than obsession with artificial sweeteners, seed oils, etc. Artificial sweeteners can help avoid overeating if used strategically.

"There are bigger fish to fry." – Ben Greenfield (45:47)

7. Biohacks and Supplements: What Works and What Doesn’t

• Muscle Stimulation Suits (46:00–47:41)

  • Full EMS suits can be painfully effective, but are inconvenient and lead to major soreness. Best saved for certain scenarios.

• Useless Fads: Thermogenic Supplements (48:21–48:24)

  • Most “fat burning” pills (raspberry ketones, green tea extract) have negligible impact on real-world fat loss.

• Surprisingly Useful: GLP-1 Agonists (Weight-loss Drugs) (48:24–52:02)

  • Ben sees GLP-1 agonists (e.g., semaglutide, tirzepatide, retatrutide) as groundbreaking but over-prescribed at high doses.
  • Microdosing (250mcg, 3x/week) can help retrain appetite with fewer side effects, potentially acting as “training wheels” for long-term behavior change.

"I think GLP agonists are some of the most useful weight loss compounds that we’ve ever developed through science." – Ben Greenfield (48:24)

• Risks & Long-term Use (54:23–56:58)
  • Not appropriate for those with eating disorders.
  • Using at high doses can impair muscle retention, cause nausea, and blunted enjoyment for life.

8. Extreme Biohacks: The Most Outrageous Things Ben Has Tried

• Young Plasma Infusions from healthy donors (Texas): Felt “unstoppable,” increased clarity, libido, and recovery (99:17–99:51).
• Full-body Stem Cell Injections: Under anesthesia, head-to-toe (66:20).
• Filtering Blood for Spike Proteins (Tijuana): Via jugular, then re-infused over days (66:32).
• Stellate Ganglion Nerve Block: Resets vagus nerve, boosts HRV, used for PTSD but also bio-optimization (67:39).
• High-dose Psychedelics and Entheogens: Years of experimentation; Ben cautions about spiritual risks, describes “crossing portals.” Combined with his wife, it profoundly deepened their relationship.
• On the Dangers and Spiritual Side of Psychedelics:
  • Real risks of psychological/spiritual harm for some.
  • Traditional use meant interacting with spirits/entities—he urges caution.

"These are like the nuclear bombs of the spiritual world. ... You have to be way more careful with this stuff than what a lot of people think." – Ben Greenfield (74:56)

9. Healing & Spiritual Fulfillment

• Faith as the Path to Lasting Forgiveness (84:07–88:50)
  • Ben explains why, from his perspective, psychedelics, while sometimes helpful, are a temporary fix. True freedom from shame and guilt comes from spiritual practice/faith.
  • Stresses that his standpoint is personal, but also recognizes similar concepts (e.g., Yom Kippur in Judaism).

"The eternal hole in the soul that can only be filled by something eternal." – Ben Greenfield (88:46)

10. Essential Lab Testing & Anti-Aging Skin Protocols

• Lab Tests Ben Recommends (92:28–95:28)

  • Don’t obsess over environmental toxin tests—they can be unreliable.
  • More useful: genetic test, quarterly blood panel, annual micronutrient screen, hormone panel (blood, urine, saliva), gut health (“poop test”), and food allergy test (Zoomer, Cyrex).

• Skin & Anti-Aging Regimen (95:28–100:17)

  • Collagen (20–40g), essential amino acids, weekly derma rolling, clay masks, red light therapy.
  • Topicals: Young Goose for peptides & bioactive compounds.
  • Occasional extreme measures: stem cells and plasma transfusions.

• Cost of Young Plasma Therapy: ~$40,000 per session, effects lasted months.

"I think a lot of this stuff just adds up because I’ve also done, like, stem cells in the face and exosome facials. But I think the daily routine—like the daily in and out things that I do—make a pretty big difference." – Ben Greenfield (99:57)

Memorable Quotes & Timelines

• [03:20] Ben: "If you step back and look at brain health in general … you need to do things that provide fuel for the brain."
• [15:45] Ben: "There’s nothing as powerful [for glucose disposal] as lifting weights … muscle is like a metabolic sink that sucks up glucose."
• [18:32] Ben: "Metabolically, cold appears to be pretty good for women for things like fat burning, sugar stabilization, etc."
• [25:10] Ben: "If your goal is just pure cardiovascular benefits, then working out in a hot environment might be superior. But if your goal is strength, power … then not so much."
• [30:19] Ben: "Concurrent training, meaning strength and cardio together, is the most superior form for fat loss."
• [45:47] Ben: "There are bigger fish to fry."
• [48:24] Ben: "I think GLP agonists are some of the most useful weight loss compounds that we've ever developed."
• [74:56] Ben: "[Psychedelics] are like the nuclear bombs of the spiritual world. … You have to be way more careful."
• [88:46] Ben: "The eternal hole in the soul that can only be filled by something eternal."
• [99:57] Ben: "I think a lot of this stuff just adds up … But I think the daily routines make a pretty big difference."

Episode Highlights by Timestamp

• 00:01–03:00: Intro, adaptogens, memory, knowledge retention strategies
• 03:00–06:55: Diet for brain health, Mediterranean fats, plant vs. animal protein
• 06:55–11:41: Digestive enzymes, meal timing, GDAs, bitters
• 15:45–17:17: Lifting weights, cold plunges for blood sugar
• 17:17–23:10: Cold exposure: gender contrasts, optimal timing
• 23:10–27:58: Sauna, heat, and temperature on exercise performance
• 30:19–36:09: Fat loss: concurrent training, zone 2 myths
• 38:48–45:05: Signs of overtraining, blood markers, caloric balance over diet fads
• 46:00–52:02: Muscle stimulation suits, best/worst biohacks, GLP-1 agonist insights
• 60:30–71:46: Extreme biohacks: plasma therapies, stem cells, psychedelics, spiritual risk
• 83:49–88:50: Lasting healing, faith, holes in the soul
• 92:28–100:17: Lab tests every biohacker should get, Ben’s skin/longevity toolkit
• 98:55–101:44: Cost/impact of youth plasma therapy, daily routines, lasting benefits

Final Thoughts

Ben Greenfield’s approach is simultaneously adventurous and evidence-driven. The episode underscores the importance of foundational habits (diet, movement, strength training, proper supplementation) while offering a window into the outer edges of biohacking and longevity. Ben’s transparency around limits, risks, and spiritual considerations is a crucial counterweight to the allure of quick fixes and radical interventions.

For more on Ben Greenfield’s routines and research, check his newly revised manual ‘Boundless.’