Chitosan

Deacetylated chitin comes from the exoskeletons of arthropods.

Mechanism of Action

  • Bile acid sequestration and fat binding in GI tract; also acts as a dietary fiber as it is not readily absorbed.

Dose

  • 1000 -1200mg BID; can be dosed up to 4000mg per day.

Evidence

  • In a Cochrane meta-analysis of 14 trials, n=1131, the following results were all statistically significant (p< 0.001):

    • Weight loss averaged 1.7kg (1.3 - 2.1kg) or 3.4 (2.9 - 4.6 lbs.)

    • Total cholesterol decreased by 0.2mmol/L (0.1 - 0.3)

    • Systolic BP decreased by 5.9mmHg (4.6 - 7.3)

    • Diastolic BP decreased by 3.4mmHg (2.4 - 4.4)

    • All

  • The better controlled, larger, longer trials showed less change.

Reference

  • Ni Mhurchu, et al. Cochrane Database Syst Rev. 2005 Jul 20;(3):CD003892

Adverse Effects

  • No different from placebo; some nausea and diarrhea have been reported

  • Chitosan may reduce absorption of fat soluble vitamins (A, D, E, K)

Interpretation

  • Chitosan is safe, but has little clinical effect on weight loss

(VoroN, Shrimp, openclipart.)