A number of previous trials investigating the effect of
chitosan on body weight and lipids have been published, but
results are conflicting. A meta-analysis of five Italian trials
involving a total of 386 participants indicated a mean
difference of 3.3 kg weight loss between the intervention
and placebo group.8 However, the trials included in the
meta-analysis were not retrieved by searching electronic
databases, but were obtained from a single manufacturer and
published in a single journal over a 2-y period. They used a
similar study design (a trial duration of 28 days and an
energy-restricted diet), but it is unclear if intention-to-treat
analyses were employed, and no description is given of the
composition or dose of chitosan used. It is unclear if the
individual patient populations may have overlapped