How to Increase Your Health Span and Longevity: According to a Geriatrician Who Treats 100-Year-Olds

Episode Overview

• Host Simon Hill interviews Dr. Deborah Kado—a board-certified, fellowship-trained geriatrician and gerontologist, Professor of Medicine at Stanford University, clinician at the Palo Alto VA, former director of the Bone Clinic at UC San Diego, and former faculty/clinician at UCLA (1998–2012)—to contrast the clinical reality of geriatric medicine with the popularized "longevity science" movement.
• The conversation explores the history and demographics of geriatric care, reframing "healthspan" into "healthy longevity," and applying the "Age-Friendly Health Systems" 4Ms (and 5Ms) framework to preserve functional independence in older adults.
• Dr. Kado breaks down the evidence surrounding bone health, posture, fall prevention, and osteoporosis medications, detailing both the efficacy of drugs like bisphosphonates and the real statistical risks of media-sensationalized side effects.
• The discussion concludes with actionable, evidence-based insights into polypharmacy, optimal body weight in older age, the gut microbiome's surprising role in active Vitamin D metabolism and sleep regularity, and identifying reversible mimics of dementia.
• Disclosures: Dr. Kado discloses no commercial conflicts of interest, noting her work at Stanford and the VA. Podcast sponsors presented by Simon Hill include ProLon (a 5-day fasting-mimicking diet developed at USC's Longevity Institute; prolonlife.com/theproof for 15% off + $40 bonus gift, noting autophagy won a Nobel Prize in 2016), Swimclub (a 90-day male fertility/sperm health supplement protocol developed with Stanford urologist Dr. Michael Eisenberg; swimclub.co/theproof with code THEPROOF for 25% off first order, noting sperm takes 72 to 90 days to develop, male factors are involved in ~50% of infertility cases, and one individual customer—not in a controlled trial—increased total sperm count from 217 million to close to 600 million in 90 days), IM8 (a daily foundational nutritional supplement system with 19 ingredients, NSF Certified for Sport, containing 200 mcg Methylcobalamin B12, 55 mg Choline, and 30 mg Saffron extract, noting B12 deficiency is associated with a 2- to 4-fold increase in cognitive impairment; im8health.com with code SIMON for 10% off + free welcome kit), and Function Health (a lab testing service offering 160+ lab tests per year for $1/day; functionhealth.com/simonhill with code SIMON25 for a $25 credit).

Key Concepts

• Gerontology vs. Geriatrics and Workforce Realities: Dr. Kado explains that "longevity science" is essentially a sexier term for gerontology—the study of aging at any point in the lifespan from biological, medical, social, philosophical, policy, or psychological angles (often by PhDs). In contrast, a geriatrician (a term coined in 1909 by New York City physician Ignatz Nascher) is an MD or DO who completes 4 years of medical school, 3 years of internal or family medicine residency, and 1 additional year of fellowship training to clinically care for older adults. Despite an aging population, there are only about 7,000 practicing board-certified geriatricians in the US—fewer than when Dr. Kado started. Furthermore, while medical students often estimate that 10% to 20% of older US adults live in nursing homes, the actual figure in long-term care is only 2% to 4%. While reaching 100 disease-free is more common now than it used to be, Dr. Kado hedges that she cannot give exact statistical estimates offhand for how common it is.
• Mindset, Social Connection, and "Healthy Longevity": How we view aging and live socially profoundly impacts outcomes. Dr. Kado cites research by Yale psychologist Becca Levy using the Baltimore Longitudinal Study of Aging, where participants surveyed in their 30s and genotyped in the late 1990s for APOE4 (where two copies substantially increase dementia risk) showed a 50% decreased risk of developing dementia decades later if they held positive attitudes toward aging at age 30—a finding that held true for both APOE4-positive and APOE4-negative individuals (though Dr. Kado notes a "chicken and egg" caveat regarding whether positive psychology directly alters biology or drives proactive health behaviors). Socially, during a VA home visit in Reseda in a 1,200 sq ft, 3-bedroom home, Dr. Kado saw a non-related family housing a 78-year-old veteran in the same bedroom as their 12-year-old son, noting they were a much happier, thriving household than wealthy, lonely households she visited in 90210 (Beverly Hills). She also rejects the term "healthspan" in favor of "healthy longevity," arguing that being diagnosed with a chronic illness like rheumatoid arthritis or ulcerative colitis at age 40 does not mean one's healthspan is over.
• The 4Ms (and 5Ms) of Age-Friendly Health Systems: Created by Dr. Mary Tinetti at Yale alongside the John A. Hartford Foundation, the Institute for Healthcare Improvement, and a Catholic hospital foundation, this framework guides geriatric care through 4Ms: What Matters (patient goals, most commonly living independently at home), Mobility, Mentation (cognition), and Medication (reviewing lists and de-prescribing). A 5th M gaining traction is Multimorbidity (how multiple conditions interact), and Dr. Kado notes there are up to 10Ms total.
• Posture, Vertebral Fractures, and Functional Power: While about one-quarter (25%) of hip fracture patients die within 1 year, Dr. Kado's research revealed that vertebral fractures (1, 2, 3, 4, or >5) and spinal curvature itself (measured in a subset of women using an architect's flexi-curve) also predict a steeper upward mortality curve, with death certificates showing many die of pulmonary causes like emphysema, pneumonia, or pulmonary embolus. Exercise interventions are vital—such as the LIFTMOR trial by Dr. Belinda Beck in Australia and work by Dr. Lora Giangregorio at Waterloo showing heavy resistance and impact training build bone density with zero complications even in patients with vertebral fractures—but require continuous adherence. Dr. Kado illustrates this with a 90-year-old male patient with kyphosis (but no osteoporosis) who improved during a 3-times-a-week, 12-week yoga intervention for back extensor strengthening, only to lose his functional gains because researchers took 6 weeks after the trial ended to conduct his follow-up exam. Furthermore, because fast-twitch muscle fibers decline with age, Dr. Kado's force-plate research separating strength from velocity showed that coordinated power (how quickly force is produced) is the critical metric for preventing falls. Clinically, she observes that into their 90s, dancers age the best (combining coordination, mobility, social engagement, and memory) and wind instrument players do exceptionally well due to lung capacity and breathing protection, outperforming tennis players.
• Osteoporosis Pharmacology, Risks, and Sequencing: Alendronate (Fosamax), the first bisphosphonate FDA-approved in the US in 1995, reduces fracture risk by about 50% in RCTs by shutting down osteoclasts (bone-resorbing cells) while favoring osteoblasts (bone-forming cells). Media backlash in 2005–2006 over osteonecrosis of the jaw (ONJ) and in 2008 (Diane Sawyer) and 2016 (New York Times and Wall Street Journal) over spontaneous atypical femur fractures frightened many patients away from treatment. However, ONJ risk is about 1 in 1,000 in cancer patients receiving 4 times the osteoporosis dose intravenously, and only 1 in 50,000 to 1 in 100,000 for oral weekly pills; from 2008 to 2021 in her bone clinic, Dr. Kado saw only 1 non-cancer case (a non-English-speaking patient who didn't know to stop the drug, and it was treatable). For atypical femur fractures, Southern California Kaiser orthopedic surgeon Rick Dell reviewed every hip fracture X-ray and showed risk increases with longer oral bisphosphonate duration and is 9 times higher in small, thin-framed Asian females; a German researcher's presentation (~2 years ago) suggested bisphosphonates may compromise microscopic blood supply to the outer bone cortex, leading to radiographic "beaking" and brittle bone. Other FDA-approved options include Teriparatide (approved ~2002; daily anabolic injection whose 2-year black box warning—based on rats given 70 times the human dose developing bone tumors—was removed after 20 years on the market with zero human bone tumors), Denosumab/Prolia (approved 2010; once-every-6-months monoclonal antibody injection effective over 10 years, though stopping causes rebound bone resorption and vertebral fractures), Abaloparatide (approved 2017; daily anabolic injection limited to 2 years; neither teriparatide nor abaloparatide showed hip fracture reduction in trials, only vertebral), and Romosozumab/Evenity (2 shots a month for 1 year; mimics exercise best, produces the largest bone density gains, and reduces both vertebral and hip fractures). Crucially, every non-bisphosphonate drug must be followed up with a bisphosphonate upon cessation to prevent losing bone gains.
• Polypharmacy and the Geriatric BMI Paradox: Large observational and epidemiologic studies demonstrate that the more medications and supplements a person takes, the worse they do health-wise—exemplified by Dr. Kado's 100-year-old patient who takes fewer than 5 medications and no supplements (except prescribed Vitamin D), and a bone clinic patient who arrived with a cooler of 25 supplements while suffering unexplained fractures despite normal bone density and a negative secondary workup. Dr. Kado also rejects unproven longevity compounds (like NAD, resveratrol, rapamycin, and caloric restriction), noting that while PhD scientists genuinely believe in and ingest or inject them, biology and aging are too complex to recommend them clinically. Similarly, contrary to the longevity movement's focus on leanness, extra weight in postmenopausal women and older adults acts as an "insurance policy" during hospitalization. Large observational studies indicate the optimal BMI for older adults (men and women) is around 27, whereas a BMI under 22 is a risk factor for poor outcomes. Regarding widespread GLP-1 use for weight loss, Dr. Kado notes that while long-term diabetes data is reassuring, we lack the long-term data to know for sure how it will impact frailty in old age.
• The Gut Microbiome, Active Vitamin D, and Sleep Regularity: In the MrOS (osteoporotic fractures in men) study across 6 US sites (Portland, OR; San Diego, CA; Palo Alto, CA; Minnesota; Alabama; Pittsburgh, PA), Dr. Kado collaborated with Eric Orwoll, Rob Knight, and an expert at the University of Leuven (Belgium) to analyze stored serum and gut microbiomes. They found that storage Vitamin D (25-hydroxyvitamin D) correlated with sunny latitudes (weather maps) and had a flatline (zero) relationship with the gut microbiome. However, men with greater gut microbiome diversity—specifically butyrate / short-chain fatty acid-producing bacteria—had higher levels of the active hormone (1,25-dihydroxyvitamin D) and vitamin D flux regardless of latitude. Dr. Kado hedges that because this data was cross-sectional, they cannot claim cause and effect ("chicken and the egg problem") and could not directly test if higher active Vitamin D translated to better clinical outcomes. She also notes that while the VITAL trial (testing 2,000 IU of Vitamin D vs. placebo in 25,000 people, with ~12,000 measured at baseline) and UK Biobank data showed no benefit for cardiovascular disease, cancer, falls, or fractures even in deficient subsets, UK data supports a role in immunity. In the same MrOS cohort, 7-day armband actigraphy and sleep questionnaires revealed that men with the most regular sleep patterns (consistent bed and wake times) also had the most diverse gut microbiomes and more favorable butyrate-producing bacteria.
• Mixed Dementia and Reversible Cognitive Mimics: Most clinical dementia is "mixed dementia"—a continuum of Alzheimer's and vascular/small vessel disease seen on neuroimaging. Dr. Kado hedges on whether cognitive brain exercises reverse dementia pathology, noting nutrition, physical activity, and cognition trials are technically difficult and daily function matters far more than small point improvements on a test scale. Critically, rapid cognitive dips are often caused by reversible mimics of dementia—such as hearing loss, mood disorders, delirium, and over-medication. She illustrates this with a 79-year-old former tennis player (whose wife/caregiver is 14 years older, age 93) presenting with a 2-month cognitive decline; because he accurately named the cover subject of his favorite magazine, Dr. Kado knew his neurons were intact and traced the cognitive dip to delirium/inflammation from a swollen, infected knee replacement.

Quotes

• At 0:00:05 - "Yes, because at a party, everybody wants to talk about longevity, but who wants to talk about gerontology?" - Dr. Kado explaining why the rebranding of aging science has captured public attention while traditional geriatric fields remain overlooked.
• At 0:02:14 - "So a gerontologist is someone who studies aging at any point in the lifespan and from all different types of angles, so it could be from a biological angle, it could be from a medical angle, it can be from a social angle, philosophical, just a policy, all over the spectrum, psychology, whereas a geriatrician is actually a practitioner, usually an MD or a DO, who gets specialized training in how to provide clinical care to older adults." - Clarifying the foundational difference between aging researchers and clinical practitioners.
• At 0:05:53 - "An internal medicine teacher once told me, if you don't think of the diagnosis, you'll never make the diagnosis; same thing, if you never encounter a geriatrician, why would you think to become one?" - Explaining the systemic shortage of geriatricians (only ~7,000 in the US) due to lack of medical school exposure.
• At 0:14:16 - "And she found that when she paired those initial surveys when these guys are 30 to whether or not they developed dementia in the end, that those who had better attitudes towards aging had a 50% decreased risk of developing dementia many, many decades later." - Discussing Becca Levy's Yale study using Baltimore Longitudinal Study of Aging data on mindset and dementia risk across APOE4 genotypes.
• At 0:19:20 - "The goal is what's important to the patient. So that's what all the geriatricians who we teach say: you've got to assess what matters, because what matters differs." - Introducing the core philosophy of geriatric medicine and the first "M" of the Age-Friendly Health Systems framework.
• At 0:20:04 - "And most commonly, what matters to an older adult is to be able to be independent and live independently and hopefully stay in their own home." - Highlighting the primary functional goal of most geriatric patients, rather than abstract biomarker optimization.
• At 0:22:05 - "So are you telling me that if you're 40 and you get rheumatoid arthritis, your healthspan is done because you have to go now for infusion therapies and you're at the doctor's office and it's a chronic health condition and you're at risk for all these other things, then your healthspan is over? I don't like to frame it that way." - Critiquing the popular concept of "healthspan" for alienating individuals living well with chronic conditions.
• At 0:22:39 - "So that's why I call it healthy longevity, because hopefully you can live a long time, and just because you have a chronic condition doesn't mean that your healthspan is over." - Providing a more inclusive, function-oriented alternative to the term "healthspan."
• At 0:25:39 - "I'm sad because there's just so many basic things that actually don't need to break your pocketbook that you can do to help your health." - Reacting to the commercialization of expensive longevity interventions versus low-cost lifestyle fundamentals.
• At 0:27:52 - "In fact, I think people, 'Oh, don't tell me what I already know: eat right, do physical activity, sleep, you know, you'll be fine.' That's boring. 'Tell me what's new, tell me what I can do to extend my life by X number of time.' Yeah, that's what's going to sell, that's what's going to get clicks, etc." - Explaining why media and consumers gravitate toward unproven longevity hacks over proven health basics.
• At 0:39:01 - "If you touch an older adult, you should be aware of what the 4Ms are, which is: what matters to them, how are they moving, are they mentating, and are you reviewing the medication list? And there's actually a 5M—there are actually 10Ms, but don't ask me to name them—but the fifth M, which is getting more traction now, is multimorbidity." - Outlining Dr. Mary Tinetti's clinical checklist for evaluating older adults.
• At 0:49:07 - "If I could peg what I think, based on experience of watching my patients, those who've done well: it's the dancers." - Sharing her clinical observation on which physical activity best preserves coordination, cognition, and mobility into a patient's 90s.
• At 0:57:48 - "Every single drug that has been FDA-approved since, which there are amazing tools out there, they all need to be followed up with a bisphosphonate in the ideal world." - Emphasizing the critical rule of sequential osteoporosis therapy to lock in bone density gains after stopping anabolic or monoclonal antibody drugs.
• At 1:01:09 - "We know from large observational or epidemiologic studies that the more medications you are on, including supplements, the worse you might do health-wise." - Warning against polypharmacy and massive supplement stacks in the pursuit of health.
• At 1:13:40 - "If you look at large observational studies, the optimal BMI for an older adult is probably 27, men and women, and that's more than I am. And if you get lower, like less than 22, that's a risk factor, broadly speaking. So I think it's more about function." - Challenging the cultural obsession with leanness by citing geriatric epidemiology on protective body weight.
• At 1:14:02 - "Can you get up from the floor? If you're on the floor and you find yourself—can you get up by yourself? I don't care what weight you are. I mean, you could be pretty heavy, and if you get up from the floor and you're super heavy, I'm doubly impressed." - Defining real-world physical function as a far superior metric of aging health than body weight alone.

Takeaways

• Test and Train Your Balance and Power: Assess your mobility using Dr. Kado's progressive clinical protocol (standing up from a chair without using your arms, narrowing your stance, holding a semi-tandem and full tandem stance with one foot directly in front of the other on both sides, lifting a single leg on both sides, and trying it with eyes closed—noting difficulty often starts in one's 40s). Train fast-twitch muscle fibers for coordinated power, and consider taking up dancing (for coordination, mobility, social engagement, and memory) or playing a wind instrument (to protect lung capacity and breathing).
• Maintain Consistency in Spine-Strengthening Exercise: Protect your posture and pulmonary health by strengthening back extensors and engaging in supervised heavy resistance/impact training, but never treat exercise as a temporary fix—stopping for even 6 weeks can erase functional gains.
• Follow Strict Protocols for Osteoporosis Medications: Before starting a bisphosphonate, complete any needed tooth extractions, floss regularly, and treat gingivitis to minimize the already rare risk of osteonecrosis of the jaw. If you are on long-term oral bisphosphonates (especially if you are a small, thin-framed Asian female), monitor for thigh pain or radiographic "beaking" on X-ray/DEXA and stop the drug if they appear to reduce atypical femur fracture risk. Never stop non-bisphosphonate bone drugs (like Denosumab/Prolia, Teriparatide, Abaloparatide, or Romosozumab/Evenity) without transitioning to a bisphosphonate to prevent rebound bone loss and fractures.
• Audit and De-prescribe Unnecessary Medications and Supplements: Work with your physician to strip away excessive supplement stacks (such as Dr. Kado's bone clinic patient who she advised to stop taking a cooler of 25 supplements) and avoid unproven longevity compounds like NAD, resveratrol, and rapamycin. Specifically review your medication list to de-prescribe long-term sleeping aids like benzodiazepines (which impair cognition and increase fall risk) and long-term proton pump inhibitors like omeprazole (which alter stomach pH, impair nutrient absorption, and are associated with worsening cognition, kidney function, and bone fractures).
• Prioritize Functional Independence Over Leanness in Older Age: Avoid dropping to a BMI below 22 as an older adult; recognize that a BMI around 27 provides a physiological "insurance policy" during hospitalizations, and focus instead on functional capabilities like being able to get up off the floor unassisted.
• Eat 40 Different Plants Per Week: Follow the findings of Prof. Rob Knight and the American Gut Project by consuming around 40 diverse plant foods weekly (counting herbs and spices) to maximize gut microbiome diversity and support butyrate/short-chain fatty acid-producing bacteria, which correlate with higher active Vitamin D (1,25-dihydroxyvitamin D) levels.
• Target Vitamin D Repletion Pragmatically: While large trials like VITAL show routine Vitamin D supplementation does not prevent cardiovascular disease, cancer, falls, or fractures in the general population, if you have bone health concerns or a documented deficiency, work with a clinician to replete storage Vitamin D (25-hydroxyvitamin D) to a target range of 30 to 50 ng/dL, which also supports immune function.
• Keep a Strict Sleep-Wake Schedule: Go to bed and wake up at the exact same time every day; 7-day actigraphy data shows that sleep regularity directly correlates with greater gut microbiome diversity and beneficial butyrate-producing bacteria.
• Investigate Reversible Causes for Sudden Cognitive Decline: If an older loved one experiences a rapid cognitive dip over a few months, do not automatically assume irreversible dementia progression; ask specific questions about their daily interests to test neuronal integrity and have a physician evaluate for reversible mimics including localized infections/inflammation causing delirium (like an infected joint replacement), hearing loss, mood disorders, and over-medication.