Glucosamine is a supplement that is taken by many people to reduce the pain caused by osteoarthritis. Whether it actually succeeds in doing so is a matter of debate: studies show a small effect hardly distinguishable from placebo. However, the track record for our purposes is much better: several studies show reduced mortality in humans1,2 and increased lifespans in rodents and worms.
Vince Giuliano of anti-agingfirewalls.com has written an extensive overview of the benefits of glucosamine supplementation for longevity3.
Doses of 1500 mg per day have been shown to be safe, with many studies suggesting higher amounts would be safe as well.
We take 1 tablet of 1000mg glucosamine-HCL per day. Note that the other common form, glucoseamine-sulfate(2KCl stabilized), contains less glucosamine per 1000mg.