Laugh Lines with Kim & Penn Holderness
Episode: Debunking Health Trends with Dr. Eric Topol
Release Date: January 20, 2026
Guests: Dr. Eric Topol (world-renowned cardiologist and researcher)
Episode Overview
In this episode, Kim and Penn Holderness bring back the ever-popular Dr. Eric Topol to cut through the noise and debunk the latest viral health trends. Known for his no-nonsense, evidence-based, and occasionally “persnickety” approach, Dr. Topol answers listener questions about everything from protein fads, weighted vests, and collagen to the prevention of Alzheimer’s, the role of functional medicine, new blood-based health tests (including “brain clocks”), and whether popular supplements and routines are worth your time or money.
The tone is light, humorous, and relatable—true to the Holderness style—with Dr. Topol offering both reassurance and tough love about trendy advice flooding our feeds and supermarket shelves.
Key Discussion Points & Insights
1. [09:12] Welcome Back Dr. Topol
- Dr. Eric Topol is reintroduced as an evidence-driven expert in digital health, genetics, and AI.
- The hosts share listener feedback, praising Dr. Topol’s candid myth-busting and wishing him to “stay persnickety.”
2. [10:12] The Protein Craze: How Much Is Too Much?
Q: “How much protein is too much, and what happens if you consume too much?”
- Recommended Intake: The recommended daily allowance (RDA) is 0.8g per kg of body weight. Even doubling that for active people is a “red line.”
- Real-World Math: For a 150lb (68kg) person, about 55g is the RDA; up to 80–100g might be reasonable, but the current trend (e.g., 1g per pound) is excessive.
- Risks:
- Too much protein isn’t stored—“you basically pee it out” ([10:39]).
- Excess can promote inflammation, especially from animal protein ([11:57]).
- Ultra-high-protein supplements (“David bars, plant extracts like olestra”) may cause side effects like diarrhea and unnecessary expense ([13:55], [14:12]).
- Plant vs. Animal Protein:
- Plant-based is preferable and less likely to promote inflammation ([17:49]).
- Nuts good for protein, but high in fats; “you need some fat too” ([18:46]).
- Dr. Topol: “We've gotten absolutely crazy about [protein] and there's no data to support it.” ([15:38])
- Notable Quote:
- "No, you should not take in one gram per pound… that's plenty, plenty." – Dr. Topol [13:44]
3. [19:33] Weighted Vests and “Rucking” Craze
Q: Are weighted vests really better for bone density?
- Weighted vests (and “rucking”) are a fad, not a miracle—described as “like a cult” ([20:18]).
- Some small studies show benefits, but resistance training, planks, bands, and push-ups are equally (or more) effective, cheaper, and safer ([21:00]).
- Risks: Possible injury, especially if used carelessly or not built up gradually ([23:00]).
- Notable Quote:
- “There are so many safer and inexpensive ways… The net benefit here is questionable—particularly when you factor in cost and injury risk.” – Dr. Topol [23:25]
- Fun Moment:
- Kim: “I bent over to pick up laundry and I threw my back out!” ([22:52])
4. [27:07] Busting Collagen & Supplement Myths
Q: “Does collagen protein really help with hair, skin, nails, or joints?”
- Dr. Topol’s Answer: “Very little to no evidence.” ([27:14])
- Randomized, placebo-controlled studies are lacking. Much enthusiasm is based on anecdote, not data.
- Memorable exchange:
- Kim (joking): "They told me it would push out my wrinkles!"
- Dr. Topol: "[Laughs] I’m going to laugh at all of these, I’m afraid." ([27:35])
5. [28:20] Alzheimer’s Prevention & New Testing
- Listener Fears: Many concern about family history and prevention.
- Blood Markers:
- P Tau 217 is a new blood biomarker linked to risk—if low, “confidence you’re not going to have to worry about that” for years ahead ([29:27]).
- APOE4 genetic testing: Understand true risk, then act ([30:14]).
- Polygenic risk scores and lifestyle interventions may “fix the brain clock”.
- Hopeful Outlook:
- “This is going to emerge as a preventable disease.” – Dr. Topol [31:54]
- “Just because you're at increased risk is not deterministic… you have a lot of control on this.” ([35:21])
Personal Story ([32:22]):
- Penn shares learning he has “twin copies” of APOE4—previously terrifying, now reassuring with knowledge and active intervention.
6. [36:10] “Brain Clock” Blood Tests Explained
- Measures hundreds of plasma proteins to determine organ “pace of aging.”
- Will allow monitoring intervention effects (e.g., drugs, lifestyle) for slowing or reversing accelerated brain aging.
- “There'll be multiple ways to get accurate brain, immune system clocks... with one simple blood test and low expense.” ([37:36])
7. [38:12] Functional Medicine vs. Evidence-Based Medicine
- Functional medicine docs often order “hundreds of tests,” sometimes without a clear clinical reason—can cause expense and anxiety with little benefit ([38:42]).
- Dr. Topol: “Targeted testing based on a person’s specific risk, not testing everything under the sun.” ([39:53])
- Exceptions: “In rare cases… if it’s a real mystery,” comprehensive testing may be justified ([40:29]).
8. [41:38] Using AI for Lab Interpretation
- Uploading your lab results to ChatGPT or other AI can help detect “trends in the normal range that are going in the wrong direction”—potentially more helpful than static “reference” ranges.
- “It’s the trends that are really important… AI can see things we don’t.” ([41:59])
9. [44:28] Speed Round: Health Trend Quick Takes
- Detoxing for Parasites: “Out of my range of expertise.” ([43:34])
- Exercise vs. Sleep: “Exercise is the absolute best data… Sleep not far behind. They interact.” ([44:28])
- Cortisol Tests & Supplements:
- “Another fad… any doctor can order it, but it’s not usually worth much.”
- “I would much more favor working with your doctor about worthwhile causes. There isn’t much to do with an abnormal cortisol.” ([46:49])
- Autophagy & Fasting:
- “Just a biologic process.” Intermittent fasting? “Eat your evening meal not late, nothing after. That’s fine.”
- No evidence for extreme fasting or 36-hour fasts. ([47:56])
- Oils:
- Olive oil: “Great—should be part of your diet, not a supplement.”
- Fish oil: Get it from food. No need for supplements that “smell like a fish.”
- MCT oil: “Forget it.” Mediterranean diet is best. ([48:58])
- Lion’s Mane and Cognitive Supplements:
- “No supplement has helped cognitive health. If I made a slide summarizing the evidence, it would be blank.” ([49:26], [49:48])
10. [54:10] Odds and Ends—Trending Topics
- Zone 2 Cardio: Fine, but not superior to more strenuous exercise. “People are hawking it without data.” ([54:33])
- Fiber Maxing:
- High-fiber foods are important (aim for 25g/day).
- Fiber supplements can be of value, but only if you’re not getting enough from diet. ([55:13])
- Hard 75 Challenge:
- “Looney Tunes… just made up.” But, “If it gets you moving, all the power to you.” ([56:16])
- Sober Curious Movement:
- Drinking less is overall a good trend. Excess alcohol increases health risks, especially for sleep and, in high-risk individuals, Alzheimer’s and atrial fibrillation. ([58:53])
11. [63:46] Medical Misinformation, Influence & Vaccines
- Dr. Topol laments the wave of “predatory” influencers pushing products without evidence, while real scientific voices get less traction.
- Brief discussion of new U.S. changes to childhood vaccine recommendations (“really unfortunate… part of the anti-science movement”) and the risks of vaccine hesitancy ([64:05]).
12. [67:08] Long Covid Clinical Trial Update
- Over 1,000 people enrolled in a trial testing tirzepatide (Zepbound) for Long Covid.
- “It knocks out inflammation in the brain and body… it's as good a drug as we know.”
- Hopeful that even a 20–25% positive outcome would be a breakthrough for this underserved group. ([68:05])
13. [69:15] Wrap-Up & Closing Nuggets
- Dr. Topol is celebrated for his integrity (“He’s not trying to sell you something… If he were, I’d buy it!” – Kim).
- “He looks amazing for his age… he’s living proof.”
- Penn’s “Nugs”:
-
- Collagen: “No evidence.”
-
- Brain clock blood test: promising, not expensive.
-
- Full body MRI: not useful unless you have clear unexplained symptoms. ([70:36])
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Most Memorable Quotes
- On protein trends:
- “No, you should not take in one gram per pound… that's plenty, plenty.” – Dr. Topol [13:44]
- On supplements for cognitive health:
- “If I made a slide that summarizes their evidence, it would be a blank slide.” – Dr. Topol [49:26]
- On detoxing for parasites:
- “That’s out of my range of expertise.” – Dr. Topol [43:34]
- On the predatory state of health trends:
- “We’re in this predatory environment where people who are highly influential are hawking things… not backed up by evidence. The credible sources don’t get the same traction.” – Dr. Topol [61:59]
- On hope in Alzheimer’s prevention:
- “This is going to emerge as a preventable disease.” – Dr. Topol [31:54]
Important Timestamps
- [09:12] – Dr. Topol returns; listener comments, tone set
- [10:12] – Protein needs and dangers of excess
- [19:33] – Weighted vests/rucking debate
- [27:07] – Collagen supplements: myth or magic?
- [28:20] – Preventing Alzheimer’s: genetics, blood biomarkers, and new hope
- [36:10] – “Brain clock” test explained
- [38:12] – Functional medicine vs. targeted, evidence-based care
- [41:38] – Use AI to interpret lab results and spot trends
- [44:28] – Quick-fire myth-busting: parasites, sleep vs. exercise, cortisol, oils, fasting, brain supplements
- [54:10] – Zone 2 cardio, fiber maxing, Hard 75, sober curious trends
- [63:46] – Medical misinformation, vaccines, the lure of “secrets doctors won’t tell you”
- [67:08] – Long Covid clinical trial and future of anti-inflammatory drugs
Tone & Takeaway
This episode blends science and sanity with Holderness-style humor, ultimately advocating for curiosity, skepticism, and evidence over hype—“cutting through the BS,” as Kim puts it. Listeners are reminded to question who benefits from the latest trend, to look for data not anecdotes, and to focus on proven pillars of healthy aging: sleep, exercise, (mostly plant-based) diet, and managing true risk factors with expert help. And to laugh at ourselves—because, as Penn says, “when we age, life is like a comedy stage… and that’s why we got laugh lines.”
For Listeners
Have a question for Dr. Topol or the show?
- Leave a voicemail at 323-364-3929
- Email: podcast@theholdernessfamily.com
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