T Nation

Glucosamine Controversy


Does anybody have any more information on the alleged insulin sensitivity issue when taking glucosamine? Bottom line: Will it interfere with fatloss?


Don't know the research on the topic, but I do know that I've been taking glucosamine for a long time. It's helped my knee (scope removed 80% of the cartilage), and I've been able to both gain a significant amount of muscle and lose the resultant fat.

I tend to view experience as more important than science, so my suggestion for you would be to try it yourself and find out!

Point: If glucosamine had a small impact on your insulin sensitivity, would that be worth disregarding the potential benefit to your joint health and long-term training ability?


My thoughts would be twofold.

Does this effect take place in exercising individuals or just the sedentary?

Can you take it during a period of time that ensures you won't be eating carbs soon afterwards?

No answers, just questions...


Things to ponder on:

Diabetes. 2001 Jan;50(1):139-42. Related Articles, Links

Exercise-stimulated glucose turnover in the rat is impaired by glucosamine infusion.

Miles PD, Higo K, Olefsky JM.

Department of Surgery, University of California-San Diego, USA. pmiles@ucsd.edu

The infusion of glucosamine causes insulin resistance, presumably by entering the hexosamine biosynthetic pathway; it has been proposed that this pathway plays a role in hyperglycemia-induced insulin resistance. This study was undertaken to determine if glucosamine infusion could influence exercise-stimulated glucose uptake. Male SD rats were infused with glucosamine at 0.1 mg x kg(-1) x min(-1) (low-GlcN group), 6.5 mg x kg(-1) x min(-1) (high-GlcN group), or saline (control group) for 6.5 h and exercised on a treadmill for 30 min (17 m/min) at the end of the infusion period. Glucosamine infusion caused a modest increase in basal glycemia in both experimental groups, with no change in tracer-determined basal glucose turnover. During exercise, glucose turnover increased approximately 2.2-fold from 46 +/- 2 to 101 +/- 5 pmol x kg(-1) x min(-1) in the control group. Glucose turnover increased to a lesser extent in the glucosamine groups and was limited to 88% of control in the low-GlcN group (47 +/- 2 to 90 +/- 3 pmol x kg(-1) x min(-1); P < 0.01) and 72% of control in the high-GlcN group (43 +/- 1 to 73 +/- 3 pmol kg(-1) 1 min(-1); P < 0.01). Similarly, the metabolic clearance rate (MCR) in the control group increased 72% from 6.1 +/- 0.2 to 10.5 +/- 0.7 ml kg(-1) x min(-1) in response to exercise. However, the increase in MCR was only 83% of control in the low-GlcN group (5.2 +/- 0.5 to 8.7 +/- 0.5 ml x kg(-1) x min(-1); P < 0.01) and 59% of control in the high-GlcN group (4.5 +/- 0.2 to 6.2 +/- 0.3 ml x kg(-1) x min(-1); P < 0.01). Neither glucosamine infusion nor exercise significantly affected plasma insulin or free fatty acid (FFA) concentrations.

In conclusion, the infusion of glucosamine, which is known to cause insulin resistance, also impaired exercise-induced glucose uptake. This inhibition was independent of hyperglycemia and FFA levels.


Ann Pharmacother. 2006 Apr;40(4):694-8. Epub 2006 Mar 28. Related Articles, Links

Effect of glucosamine on glucose control.

Stumpf JL, Lin SW.

University of Michigan Health System and College of Pharmacy, Ann Arbor, MI 48109, USA. jlstumpf@umich.edu

OBJECTIVE: To review the literature regarding the effect of glucosamine on glucose control. DATA SOURCES: English-language articles on the effects of administration of exogenous glucosamine on glucose control were identified through a search of MEDLINE (1966-March 2006), EMBASE (1988-March 2006), and International Pharmaceutical Abstracts (1970-March 2006) databases using the search terms glucosamine, blood glucose, and diabetes mellitus. Abstracts of articles were then reviewed to determine relevance to the topic. Bibliographies of selected articles were screened for other pertinent references.

DATA SYNTHESIS: Theoretically, glucosamine may alter glucose metabolism. Insulin resistance has been noted following intravenous administration of glucosamine in animal studies; however, these findings have not been confirmed in humans. Alterations in glucose control have not been documented in long-term efficacy studies using oral glucosamine for osteoarthritis or in trials of short duration conducted in healthy or diabetic subjects. The long-term effects of glucosamine in patients with diabetes have yet to be established in well-controlled trials.

CONCLUSIONS: Small, short-term studies suggest that glucosamine may be used in selected patients without affecting glucose control; however, data in patients with diabetes mellitus are limited, and close monitoring for potential changes in glucose control is recommended.

At this point in time, evidence is laking to make any form of recommendation beyond the diabetic or pre-diabetic individual.

Any other position would be premature and not backed by research.

Still, it offers interesting possibility (possible protection of atherosclerosis by glucosamine for example)



hey if your cartlidge goes then you wont be able to excercise so you'll even be worse off then before. maybe you want to stick to lower carb per meal diets when going on heavy doses of glucosamine due to the fact that you might not have as good of a transport system as before. you'll still be able to glycogen replenish your muscles.

if you are so afraid then you can go for chondroitin sulfate or msm. i take all three in mixed tablet form. the chondroitin is the most expensive of the three. laters pk


Whats the difference between Glucosimine and L-Glutamine? Do they both work for joint repair?


They both have "Glu" and "mine" in their names. Other than that, they are completely different substances.

I recommend doing a search on each to learn more about them.


I've gotten quite lean while taking glucosamine chondroiton when that's been my goal. I don't know if it would've been easier without it. I've been taking it for years. But the real benefits outway and drawbacks in this respect, in my opinion.


Thanks for your thoughts, looks like the jury is still out on this one. AFAIK I'm not diabetic, so gluco here I come!


In addition to the Insulin/Glucose issues and for those who may not know, Glucosamine is derived from shellfish and those individuals who may be sensitive or allergic to any form of shellfish should avoid products containing Glucosamine and should ask your MD for advice.


Hate to resurrect such an old post, but I'm wondering if anyone has come across anything new in this field? I'm wondering if the verdict is out on whether or not Glucosamine will mess with insulin sensitivity. Thanks to anyone who has info on the topic.


Good resurrection.
I'm doing a literature review on joint supplements now and the data on the topic are still equivocal.

Maintaining exercise and a good diet is going to be the best predictor of glucose control, whether glucosamine is used or not.