These non-essential amino acids belong to the sulphur group along with methionine, taurine and the tripeptide glutathione. L-Cysteine is the controlling amino acid in the construction of glutathione which is a tripeptide composed of the three amino acids cysteine, glycine and glutamine. Glutathione is one of the most important antioxidants in nature. It is not quite possible to acknowledge the importance of cystein without knowing the functions of glutathione. Also see "Glutathione".
Cysteine is a non-essential water-soluble sulphurous amino acid, a powerful antioxidant and - therapeutically speaking - perhaps the most interesting one, due to its efficiency and its broad field of activity.
Its excellent ability to remove harmful substances from the body might make it suitable for both prevention and, possibly, treatment of cancer. It removes heavy metals, protects against some harmful effects of smoking and alcohol, inactivates the free radicals, and, to some degree, protects against both X-rays and nuclear radiation.
Sulphurous substances with detoxifying effects are widely distributed in nature, and have probably been used in the prevention and treatment of diseases for as long as mankind has been able to obtain knowledge concerning the human health. Garlic, used since the Egyptian antiquity, is the classic example. One could name many more. Then, they were used for a great number of illnesses ranging from psoriasis and rheumatism to mental illnesses.
However, certain sulphurous compounds are more effective than others. The main reason for the amazing spectrum of activities of cystein lies first and foremost in the special sulphuric compound of the molecule that consists of a so-called thiol group which means a sulphur atom in compound with a hydrogen atom.
This thiol group is placed at the end of the cysteine molecule and is responsible for the antioxidant activity of the amino acid. With this weapon the molecule prevents oxidation of sensitive vital structures that could otherwise cause degeneration.
When the cysteine molecule attacks the free radicals, it loses the hydrogen atom in the thiol group - in the heat of the struggle - and the remaining sulphur atom forms a compound with another sulphur atom on another cysteine molecule. Together, the two molecules form one cysteine molecule that contains two mutually connected sulphur atoms, and is therefore a disulphide. This particular compound is very strong and it is responsible for the structure in many resistant peptides and proteins, e.g. in hair and nails.
But cystine has many other biochemical functions that are not yet fully recognized. This is manifested in the fact that very low cystine values are found in people who suffer from certain types of asthma and allergies, depression and psychosis, arthritis, and hypertension.
Cystine is a stable compound that does not have any anti-oxidant effects. The active antioxidant cysteine is actually very easily transformed into the inactive substance cystine. This has to be taken into account in connection with therapy and is done by adding vitamin C to the cystein dosage, so that it does not lose its antioxidant effect before it is needed in the body. The proportional dosage between cystein and vitamin C should be 1:3. Cysteine can also be stabilized by being transformwed into N-acetyl-cysteine - normally abbreviated NAC.
Hair loss and baldness are often the result of a deficiency of the sulphur amino acids. Keratin consists of 12% cystine, and people who suffer from hair loss often have low cysteine/cystine values in their tissue. Experiments performed on both animals and humans have shown that a sulphurous amino acid supplement can increase both the diametre of the single hair as well as the density of the hair.
A female patient at the age of 30 suffered from violent hair loss. Her hair actually came off in dense tufts. Her plasma amino acid analysis showed low values of cysteine and taurine, and she started out by taking a supplement of 1 g. of cysteine; morning and evening. It did not improve her condition, but when the dosage was increased to 5 g. of cysteine twice a day, the hair loss stopped within a month.
A female patient at the age of 35 suffered from hair loss in connection with a depression. However, a supplemet of 12 g. of cysteine twice a day made the hair loss cease within two weeks. Even when the task is to provide the hair with cystine, the preferred supplement is also cysteine.
What applies to the treatment of hair, also applies to the treatment of skin. Sulphurous amino acid deficiency weakens our outer protective "membrane", the skin. Cysteine has proved to be useful in promoting skin health.
Even more vulnerable than the skin are the mucous membranes of the body. Particularly exposed are the ones in the respiratory passages if you are a smoker - passively or actively - or if you live in an air polluted area. There are hundreds of toxic chemicals in tobacco smoke, many of which they weaken the white blood cells in the lung alveoles, especially the macrophages, thereby weakening the immune response.
It is wise to protect oneself against tobacco smoke with the aid of cysteine, preferably taken along with the vitamins A, -C, -B1 (thiamin), and the minerals zinc and selenium. Of course it is best to quit smoking entirely; but what about the poor passive smokers who are forced to inhale the polluted air produced by others?
NAC
When talking about problems in the respiratory passages, cystein has yet another function: As an expectorant treatment. In this case, N-acetyl-cysteine (NAC) is used as a spray or as a dissolved sodium bicarbonate tablet. However, NAC is also effective as a tablet or a capsule for promoting lung health, sometimes in as low doses as 200 to 500 mg. morning and evening.
The NAC spray can be in other diseases in the respiratory passages. Some asthmatics use it to moderate prescription medicine (including their inhalator). Intravenous NAC used as by doctors an antidote to paracetamol poisoning.
N-acetyl-cysteine= NAC is a molecular variant of cysteine; it is patentable and therefore suitable for investment in the eyes of producers and distributors. This is probably the reason why there is a disproportionate amount of surveys on NAC which is more stable than cysteine and is said to be more effective. Whether it really is more effective has yet to be determined.
Diabetics have an increased need of both taurine and cysteine, especially under ketosis where they discharge large amounts of both amino acids. Cysteine is - along with methionine - also important to the synthesis of lipoic acid from linolenic acid. Lipoic acid has proved to be beneficial in case of diabetes where it can lower the need for insulin.
Maintains the growth of hair and nails. Used for bronchitis and asthma. Protects against free radicals. Counteracts wrinkles. Many elderly people and chronically ill can benefit from taking this amino acid. Cysteine has been used succesfully in the treatment of certain types of psychosis. Promotes skin health. Promotes the production of carotene and the absorption of iron. Promotes air passage in the respiratory organs and relieves hangovers.
Cysteine can easily be transformed into cystine, but in the process it loses some of its biological and therapeutic effects. In order to prevent this transformation, cysteine must be taken along with ascorbic acid in a 1:3 ratio. As mentioned, it is also possible to take this amino acid in the shape of N-acetyl-cysteine (NAC) which is not as easily transformed into cystine.
Therapeutic dosage
Start out with 500 mg a day - to avoid digestive problems - and then proceed to 3 or 4 g. a day. Some scientists have used up to 7 g. a day.
Attention !
Should only be given to diabetics in moderate doses, especially if they take insulin. One should note that large cysteine supplements can have straining effects on people who have a predisposition to form kidney stones and gallstones that contain cysteine. In most cases, kidney stones are not caused by cysteine, but are formed by oxalic acid and calcium deposits.
Also see "Amino acids generally" and "Amino acid complexes"
