Regular Glucosamine Use and Mortality

From the article:

>> regular glucosamine use may be a marker for a healthy lifestyle, but it is hard to distinguish the confounding effects of a healthy lifestyle from the impact of regular supplementations in an observational study.

Based on a quick survey [1], seems like various forms of glucosamine are not interchangeable. Doesn't this confound the study further given its unclear which supplements led to what outcomes?

[1] https://www.mayoclinic.org/drugs-supplements-glucosamine/art...

Glucosamine seems to be taken to treat joint pain and osteoarthritis but would a general anti-inflammatory effect be what causes a reduction in mortality if any?

Interesting preliminary investigation but there’s no mathematics that can remove confounding factors for such small effects.

Glucosamine and independently chondroitin can provoke a slight allergic reaction. That's because they're often sea derived. Perhaps lab synthesized versions wouldn't have this issue. The reaction, although not serious, can be enough to discourage their use.

For me this URL leads to a Wordpress login page.

(2020)

This is from 2020.

What if everyone got enough glycine while their blood sugar was adequate, so that their glucosamine levels topped up...

> The inverse associations of glucosamine use with all-cause mortality seemed to be somewhat stronger among current than non-current smokers

So take glucosamine and start smoking? /s