Some are — hyaluronic acid and PRP have been around for years, with mixed evidence and modest effects. The newer generation, the one I work on, aims higher: hydrogels that don't just lubricate but tell the joint to calm down by nudging immune cells away from inflammation. Those are still in preclinical and early clinical work. If a clinic offers you a 'stem cell' or 'regenerative' gel injection today, ask exactly what's in it, what trial it came from, and what the placebo arm showed. The honest answer for most patients in 2026 is: not yet, but soon.

Briefly: glucosamine and chondroitin show small, inconsistent effects in large trials — not nothing, not much. Collagen peptides have a bit more recent data but still modest. None of them regrow cartilage. They are unlikely to harm you, and if you find one helps with your symptoms, the evidence isn't strong enough to talk you out of it. But if a supplement is displacing a more effective treatment — physical therapy, weight loss, properly timed surgery — that's the part to be careful about.

Both, roughly. Some loss of muscle with age is unavoidable — the biology of motor units, hormones, and protein synthesis tilts against you after fifty. But the rate of loss is enormously modifiable: resistance training (the actual lift-something-heavy kind), enough protein, and staying ahead of the small illnesses that cause weeks of bed rest. The single biggest predictor of how strong you'll be at eighty is whether you kept lifting at sixty.

It's real. The aggregate data on weather and joint pain is messy — many studies show no effect on average — but for individuals with osteoarthritis, drops in barometric pressure and ambient temperature do correlate with stiffness and pain. Cold tightens connective tissue, slows synovial fluid, and shifts how nerves report sensation. Warming up gradually, gentle morning movement, and keeping the joint protected on cold days isn't placebo — it's working with the physics.