Introduction: Chitosan obtained from the natural bipolymer chitin abundantly derived from the exo-skeletons of crustacean, has been sucessfully used in diverse field such as Water Waste Treatment, Food Industry, Medical equipments, Biotechnology, Agriculture, Cosmetics etc. But the most recently popular and extensive use of chitosan as a supplement for fat loss. Numerous research updates are published to establish the action and effects of chitosan on human clinical trials. Here are some recent publications :

• The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults.
  Int J Obes Relat Metab Disord. 2004 Sep;28(9):1149-56.
  
  MAIN OUTCOME MEASURES: 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: The chitosan group lost more body weight than the placebo group during the 24-week intervention, but effects were small. Similar small changes occurred in circulating total and LDL cholesterol, and glucose.
  
  CONCLUSION: In this 24-week trial, chitosan treatment did not result in a clinically significant loss of body weight compared with placebo.
  
  

• Improvement of HDL- and LDL-cholesterol levels in diabetic subjects by feeding bread containing chitosan.
  J Med Food. 2003 Winter;6(4):397-9.
  
  In this work; the following parameters were evaluated: body weight, plasma cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride, and hemoglobin A(1c) (HbA(1c)). Compared with the control group.
  
  RESULTS: The patients receiving chitosan-containing bread decreased their mean levels of LDL-cholesterol and significantly increased their mean levels of HDL-cholesterol at the end of the study.
  
  CONCLUSION: These chitosan results warrant further studies over a longer period of time to evaluate if a persistent improvement in levels of lipoproteins can be attained with this strategy.
  
  

• The effect of long-term microcrystalline chitosan therapy on plasma lipids and glucose concentrations in subjects with increased plasma total cholesterol: a randomised placebo-controlled double-blind crossover trial in healthy men and women. Tampere University Hospital, Tampere, Finland.
  
  CONCLUSION: Treatment with chitosan had no effect on the concentrations of plasma lipids or glucose in healthy middle-aged men and women with moderately increased plasma cholesterol concentrations.
  
  

• Efficacy of a novel chitosan formulation on fecal fat excretion: a double-blind, crossover, placebo-controlled study.
  J Med. 2002;33(1-4):209-25.
  
  CONCLUSION: Examining the data,it was found that the period when the test compounds were given was statistically significantly different from the placebo baseline, placebo experimental, and test baseline periods. Using multiple comparisons, it was ascertained that the novel formulation containing chitosan plus psyllium husk seeds increases fecal fat excretion.
  
  

• Effect of chitosan in complex management of obesity [Article in Polish]
  Zahorska-Markiewicz B. Katedra Patofizjologii Sl. AM w Katowicach.
  
  RESULTS: Significantly higher body weight loss was noted in the chitosan-supplemented group (15.9 kg) than in the placebo group (10.9 kg) Also a greater decrease of systolic and diastolic blood pressure was observed in the chitosan group. There was no difference between the groups in the decrease of LDL and total cholesterol. No adverse effects were noted but the number of drop-outs was higher in the placebo group than in the chitosan group.
  
  CONCLUSION: Chitosan can be used as a valuable and safe adjuvant in long-term dietary treatment of obesity. Chitosan seems to accentuate the reduction of blood pressure associated with weight reduction.
  
  

• Randomized, double-blind trial of chitosan for body weight reduction.
  Pittler MH. University of Exeter, United Kingdom. Eur J Clin Nutr 1999 May;53(5):379-81
  
  CONCLUSION: The above data suggest that chitosan in the administered dosage, without dietary alterations, does not reduce body weight in overweight subjects. No serious adverse effects were reported.
  
  

• Recent advances on chitosan-based micro- and nanoparticles in drug delivery.
  J Control Release. 2004 Nov 5;100(1):5-28.
  
  Considerable research efforts have been directed towards developing safe and efficient chitosan-based particulate drug delivery systems. Methods of their preparation, drug loading, release characteristics, and applications are covered. Chemically modified chitosan or its derivatives used in drug delivery research are discussed critically to evaluate the usefulness of these systems in delivering the bioactive molecules. From a literature survey, it is realized that research activities on chitosan micro/nanoparticulate systems containing various drugs for different therapeutic applications have increased at the rapid rate.