The modern day response is get it from natural food sources. Shellfish, animal bone and cartilage - things people typically discard

There’s been a lot of research, most mixed but it is one of the few joint supplements that does have studies showing statistical beneficial outcomes. In my opinion the diabetes correlation is overblown for normal people, but if you’re already diabetic it could be an issue. Here’s the thing: results in studies are all over the place as dosage and type vary. I take glucosamine sulfate and chondroitin sulfate. For me it works, but it takes weeks to start having an effect. There have been periods I’ve stopped using them and then start feeling pain in my knees, takes another month of going back on them to have the soreness ease. And the supplements could have nothing to do with that, it could be shoes, running distance, intensity, etc. However I have always been susceptible to joint, tendon, and muscle injury (nursing a calf strain now), so I’m in the ‘if it doesn’t harm and may help go ahead and take them’ camp.

^^^^^^^^

This. I've been taking GC for years. When I stop taking it. My knees start hurting (I am 63 and run a lot). I had a break (forced because we ran out and I went to Aus for a few weeks) for a bout 3 months and my knee started hurting and got worse until I could not run. It's actually taken me the better part of 3 months to get to the stage where they are not hurting again form when I restarted taking the glucosamine. For me it seems to have an effect. So I really don't care what the research might or might not say.

---

Trust me I’m a doctor!
Well, I have a PhD :-)

Long time ago, I suffered from femoropathelar condrop. I attended a really good doctor and he prescribed glucosamine sulphate and told me to get customized insoles...I hardly could go upstairs...I was 23 or so...well, it worked...but I definitely think the insoles made most part of the job. In Spain, now, very few doctors prescribe glucosamine
....as it seems there is no real evidence. But as people say, trial and error...

---

Spaniard. Sorry for my english for the sensitive ones :P

there is nothing I can find taht says there is any reason to not take glucosamine sulfate with respect to diabetes, just the opposite:
Semin Arthritis Rheum. 2019 Aug;49(1):9-19. doi: 10.1016/j.semarthrit.2019.01.005. Epub 2019 Jan 11.
Type 2 diabetes mellitus and osteoarthritis.
indicates there is no reason not to take it and that it may be beneficial. "while other anti-OA medications may be safely prescribed in OA patients with T2DM, such as glucosamine and intra-articular hyaluronic acid." from the abstract.