The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults.
BACKGROUND
Chitosan, a deacetylated chitin, is a widely available dietary supplement purported to decrease body weight and serum lipids through gastrointestinal fat binding. Although evaluated in a number of trials, its efficacy remains in dispute.


OBJECTIVE
To evaluate the efficacy of chitosan for weight loss in overweight and obese adults.


METHODS
A 24-week randomised, double-blind, placebo-controlled trial, conducted at the University of Auckland between November 2001 and December 2002.


METHODS
A total of 250 participants (82% women; mean (s.d.) body mass index, 35.5 (5.1) kg/m(2); mean age, 48 (12) y)


METHODS
Participants were randomly assigned to receive 3 g chitosan/day (n=125) or placebo (n=125). All participants received standardised dietary and lifestyle advice for weight loss. Adherence was monitored by capsule counts.


METHODS
The primary outcome measure was change in body weight. Secondary outcomes included changes in body mass index, waist circumference, body fat percentage, blood pressure, serum lipids, plasma glucose, fat-soluble vitamins, faecal fat, and health-related quality of life.


RESULTS
In an intention-to-treat analysis with the last observation carried forward, the chitosan group lost more body weight than the placebo group (mean (s.e.), -0.4 (0.2) kg (0.4% loss) vs +0.2 (0.2) kg (0.2% gain), P=0.03) during the 24-week intervention, but effects were small. Similar small changes occurred in circulating total and LDL cholesterol, and glucose (P<0.01). There were no significant differences between groups for any of the other measured outcomes.


CONCLUSIONS
In this 24-week trial, chitosan treatment did not result in a clinically significant loss of body weight compared with placebo.
Clinical Trials Research Unit, University of Auckland, New Zealand. c.nimhurchu@ctru.auckland.ac.nz
C Ni
CN
Mhurchu
S D
SD
Poppitt
A-T
AT
McGill
F E
FE
Leahy
D A
DA
Bennett
R B
RB
Lin
D
D
Ormrod
L
L
Ward
C
C
Strik
A
A
Rodgers
D000328:Adult; D019440:Anti-Obesity Agents / Q000627:therapeutic use*; D000924:Anticholesteremic Agents / Q000627:therapeutic use; D002686:Chitin / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D048271:Chitosan; D002784:Cholesterol / Q000097:blood; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D016896:Treatment Outcome; D015431:Weight Loss / Q000187:drug effects
D019440:Anti-Obesity Agents; D000924:Anticholesteremic Agents; D002686:Chitin; D048271:Chitosan; D002784:Cholesterol