Tuesday Oct 22, 2013 (foodconsumer.org) -- A new study recently published in PLoS One has found that chitosan, a natural polymer found in the shell of shrimp and crab can effectively lead to a significant weight loss in obese men and women when used in a right dose.

For the study, researchers conducted two experiments.  The first experiment was intended to find the best dosage for the crude fat digestibility.  For this experiment, 16 pigs were assigned to receive one of four dietary treatments, basal diet, basal diet plus 300 ppm chitosan, basal diet plus 600 ppm chitosan, and basal diet plus 1200 ppm chitosan.  As a result, 1200 ppm chitosan was the best dose that reduced the crude fat digestibility, which helps weight loss. 

In the second experiment, 80 pigs were offered the same dietary treatments as those used in the first experiment and blood samples collected at baseline, day 35 and day 57 were analyzed.

Again, those on a diet supplemented with 1200 ppm chitosan reduced their daily dietary intake and body weight gain from day 35 to 57, compared with those receiving other treatments.  And it's not surprising that the researchers found that at the end of the dietary intervention, those eating the diet supplemented with the highest amount of chitosan had the greatest weight loss, compared with those using all other treatments.

Blood studies revealed that pigs eating the diet supplemented with 1200 ppm chitosan had increased serum leptin concentrations, and decreased serum C-reactive protein (CRP) concentrations.  Both changes were desirable.

The study concluded "the results of this study highlight novel endocrine mechanisms involving the modulation of serum leptin and CRP concentrations by which chitosan exhibits anti-obesity properties in vivo.

The dose 1200 ppm chitosan for a person who eats 2.2 pounds or 1 kg of foods per day is about 1200 mg or 1.2 grams.  Chitosan may render a feel of fullness and therefore reduce intake of foods leading to weight loss.

Chitosan is available as a dietary supplement in local health stores or online health food stores.  Chitosan is fairly safe to eat.  But the study suggests that it would take one month or so to see some weight loss. (DL)

Citation: Walsh AM, Sweeney T, Bahar B, O’Doherty JV (2013) Multi-Functional Roles of Chitosan as a Potential Protective Agent against Obesity. PLoS ONE 8(1): e53828. doi:10.1371/journal.pone.0053828