Bone Health, Falls, Medications & Healthy Longevity | Dr Deborah Kado

What It Covers

Geriatrician and gerontologist Deborah Kado discusses bone health, fall prevention, osteoporosis medications, and what actually predicts functional independence in older adults. Drawing on 30+ years of clinical experience, she covers the four M's framework used in geriatric care, bisphosphonate risks and benefits, deprescribing, the microbiome-vitamin D connection, and why healthy longevity is a more useful concept than health span.

Key Questions Answered

• •Attitude and dementia risk: A Yale study by psychologist Becca Levy tracked people from their 30s into old age and found those with more positive attitudes toward aging had a 50% lower risk of developing dementia decades later. This held true even for people carrying the APOE4 gene variant, which significantly elevates dementia risk. Cultivating a constructive mindset about aging is not merely psychological comfort — it appears to carry measurable biological consequences worth taking seriously from midlife onward.
• •Power training over slow resistance work: Fast-twitch muscle fibers decline faster with age than slow-twitch fibers, and it is specifically these fibers that enable the rapid force production needed to catch yourself during a trip or stumble. Kado's research used force plates to separate strength from velocity, finding that coordinated power — not raw strength alone — was the key predictor of fall-related outcomes. Including explosive or quick-movement exercises alongside conventional resistance training is essential for fall prevention, not optional.
• •Bisphosphonate safety reframed: Public fear of bisphosphonates — driven by 2008 news coverage of spontaneous thigh fractures and jaw bone necrosis — caused millions to avoid the most effective fracture-prevention drug available. Jaw necrosis risk for standard oral dosing is estimated at one in 50,000 to one in 100,000. Thigh fracture risk is higher in small-framed Asian women after prolonged use, but is detectable via X-ray or DEXA scan of the femur. Stopping the drug when early changes appear resolves the risk.
• •Deprescribing as a clinical intervention: Reviewing and reducing medication lists can reverse apparent cognitive and physical decline in older adults. Benzodiazepine sleep aids, intended for short-term use, are frequently continued long-term and increase fall risk and cognitive impairment. Long-term proton pump inhibitor use is associated with worsening cognition, kidney function, bone density, and nutrient absorption. Kado describes patients referred for apparent decline who became functionally different people after a geriatrician simply adjusted their medications — no new treatments required.
• •Microbiome diversity and active vitamin D: A study Kado conducted with researcher Rob Knight found that the standard clinical marker — 25-hydroxyvitamin D (the storage form) — showed no relationship to gut microbiome composition. However, men with greater gut microbial diversity had higher levels of the active vitamin D hormone (1,25-dihydroxyvitamin D) and more evidence of metabolic flexibility in the vitamin D system. This suggests the microbiome may influence how effectively the body converts stored vitamin D into its active, usable form.
• •Sleep regularity and gut microbiome diversity: In a study using seven-day armband monitoring plus validated sleep questionnaires, men with the most consistent sleep timing — going to bed and waking at the same time daily — had the most diverse gut microbiomes, including higher levels of butyrate-producing bacteria associated with favorable gut health. Sleep duration mattered less than sleep regularity in predicting microbiome composition. This finding connects circadian consistency directly to a measurable marker of metabolic and immune health.
• •Optimal BMI for older adults is higher than expected: Large observational studies place the optimal BMI for adults over 65 at approximately 27 — above the standard "healthy" range — for both men and women. BMI below 22 is a risk factor for poor outcomes in this population. Kado explicitly does not focus on weight reduction in older patients unless metabolic conditions like diabetes are present. Body weight functions as a physiological reserve during hospitalisation, where patients frequently cannot eat, making leanness a liability rather than an asset.