Chitosan: How crab and shrimp shells could help lower high cholesterol levels and keep your trim

The shells of crustaceans like crabs, shrimps and lobsters serve an important purpose in that they protect these creatures from predators. Now it appears that their shells can benefit humans too, particularly in terms of reducing cholesterol and aiding weight loss.

Their shells contain a natural fibre called chitin and it is a molecule within this called chitosan that is responsible for these benefits.

One person who has already benefited from its use is Anna, a 66 year-old housewife from the Midlands, who was told during a routine visit to her doctor a few months ago that she was at high risk of suffering a heart attack. This was because there is a history of cardiovascular problems in her family, and also because she was overweight, had high blood pressure and cholesterol levels all risk factors for a heart attack or stroke.

She was of course devastated to hear this news, but it was also she says the wake up call she needed and she decided to take action straight away. She was determined to avoid medication and its attendant side effects at all costs, deciding instead to follow a healthy diet and take regular exercise.

In addition to this she began supplementing with chitosan and after just four months of taking it her cholesterol and blood pressure readings and her weight went down significantly. She is delighted with the results and hopes that its continued use alongside the healthy lifestyle changes she has made will bring her readings down further still. 

Dual action reduces bad cholesterol and raises levels of good cholesterol

So how does chitosan work to produce such beneficial results like those experienced by Anna? The main reason appears to be its attraction to fat it literally makes a beeline to cholesterol and other fatty molecules it comes into contact with. Once it encounters them it binds to these fatty substances and then inactivates them.

Its fibres are made in such a way that they are able to absorb fat from your stomach and bowel, and in doing this it prevents the fat from entering your blood stream. The mixture of chitosan and fat then passes through your bowel and is expelled when you next go to the toilet.

This action not only helps reduce the amount of cholesterol being absorbed by your blood stream, it also reduces the absorption of other fatty molecules such as triglycerides which, like cholesterol, can block your arteries and increase your risk of heart disease.

Better still, it appears that chitosan can specifically reduce LDL (the bad form of cholesterol) and increase levels of HDL (the good form of cholesterol). This action was recently confirmed in an animal study conducted at the Pharmacy Department, Extremo Sul Catarinense University, in Brazil.

The scientists found that both chitosan given on its own and chitosan given together with aloe vera lowered LDL cholesterol and triglyceride levels and raised HDL levels (Phytother Res. 2006 Apr;20(4):288-93). 

Chitosan aids weight loss by inhibiting the absorption of fat and reducing your cravings for food

By inhibiting the absorption of fat, chitosan not only lowers cholesterol and triglyceride levels it also helps prevent weight gain. In an animal study, scientists from the School of Medicine, in Japan found that chitosan reduces the number of enzymes in the bowel that normally help digest fat. This action means that the fat molecules remain undigested and pass through the bowel in the faeces. The scientists also confirmed that chitosan is a safe nutrient (J Pharm Pharmacol. 2006 Feb;58(2):201-7).

US scientists have found another way chitosan promotes weight loss it appears to encourage feelings of fullness, thereby reducing your appetite and making it less likely that you will overeat.

Commenting on their findings, the researchers from the University of Pennsylvania School of Medicine, who studied chitosan and other natural fibres such as cellulose, said: Our study provides strong evidence that satiation [feeling full] underlies the cholesterol-lowering properties of insoluble dietary fibres (such as chitosan and cellulose) (Br J Nutr. 2005 Sep;94(3):331-7).

Chitosans weight loss benefits were also confirmed by a scientific review of all the available evidence on this treatment... and in the process another positive attribute it possesses was uncovered an ability to lower blood pressure. This was made possible through the Cochrane Library a worldwide virtual library that lists practically every scientific report in existence a great resource for scientists wanting to gain a wider picture about a treatment.

Using the Cochrane Library, scientists from the Clinical Trials Research Unit, Department of Medicine, University of Auckland, in New Zealand, reviewed fourteen clinical trials on chitosan, involving 1,131 participants, and concluded that: All trials indicated that chitosan preparations result in a significantly greater weight loss and a decrease in blood pressure compared with placebo (Cochrane Database Syst Rev. 2005 Jul 20;(3):CD003892).

Chitosan helps defend your liver against harmful toxins

The fact that chitosan is so effective at reducing excessive levels of fatty substances in the blood also makes it beneficial for protecting the liver. This is because your liver normally has to deal with a tremendous amount of fatty substances, which can eventually damage this important organ as a result of the toxic by-products they produce.

A team of scientists from the Central Institute of Fisheries Technology in India, studied the protective benefits of chitosan on liver tissue after exposure to strong toxins. They concluded that: The results of the present study indicated that the hepatoprotective [liver-protecting] effect of chitosan might be ascribable to its antilipidemic [fat-lowering] effect and/or antioxidant property (Toxicology. 2006 Feb 15;219(1-3):53-9).

What to take for best results
 
The recommended dosage is two 500mg chitosan capsules with 8 ounces of water taken thirty to forty minutes prior to one or two meals per day. If you are taking it to aid weight loss it is important that you also follow a balanced diet.

You should be aware that chitosan can cause stomach cramps, wind and constipation in some people. If you experience any of these side effects then simply lower the dosage until they disappear.