Cysteine - Nature Cures®

Cysteine is a sulphur containing amino acid that occurs naturally in foods and can also be manufactured by the body from the amino acid methionine. In the production of cysteine, methionine is converted to S-adenosyl methionine, which is then converted to homocysteine. Homocysteine then reacts with serine to form cysteine.

Cysteine is also found in food as cystine, an amino acid that contains two cysteines joined together. Cysteine, which can be formed from serine through the trans-sulphuration pathway, is the precursor for proteins, glutathione, taurine, coenzyme A and inorganic sulphate.

Glutathione, formed from cysteine, glutamic acid and glycine, is found in all human tissues, with the highest concentrations found in the liver and eyes. Glutathione is a potent antioxidant, protecting fatty tissues from the damaging effects of free radicals. The antioxidant activity of glutathione is attributed specifically to the presence of cysteine in the compound.

Cysteine rich foods can help to detoxify the body of chemicals and heavy metals, protect cells from free radical damage and breakdown extra mucous in the lungs. It is especially beneficial for those suffering with coughs and colds. Because it has the ability to breakdown proteins found in mucous that settles in the lungs it can be useful in the treatment of asthma, cystic fibrosis, bronchitis and other respiratory problems.

Health disorders cysteine can help to prevent and treat

Asthma
Bronchitis
Cancer
Cataracts
Hair loss
Heart disorders
Heavy metal toxicity or exposure
HIV/AIDS
Respiratory distress syndrome
Liver disease
Parkinson’s disease
Psoriasis
Rheumatoid arthritis
Virus infections

It is scientifically recommended that all individuals 1 years of age or greater should consume 25 milligrams of cysteine plus methionine (combined) for every 1 gram of food protein.

Cysteine often gets destroyed in the gastrointestinal tract as a potentially toxic free molecule. Cystine is two cysteine molecules bonded by a sulphur molecule and is used to survive the GI Tract or blood serum and get into the cells that can break the bisulphide bond to utilize the freed cysteine molecules.

Deficiency of cysteine

Deficiency is relatively uncommon but may be seen in vegetarians with low intake of the plant foods containing methionine and cysteine. Low cysteine levels may reduce one’s ability to prevent free radical damage and may result in impaired function of the immune system and neurodegenerative diseases, including multiple sclerosis, amyotrophic lateral sclerosis (Lou Gehrig’s disease) and Alzheimer’s disease.

Because the production of cysteine involves several nutrients a deficiency of methionine, vitamin B6 (pyridoxine), vitamin B9 (folate), vitamin B12 (cyanocobalamin) and s-adenosyl methionine (SAMe) may decrease the production of cysteine.

NOTE: Certain medications can cause deficiencies of these nutrients which will in turn cause a deficiency in cysteine. See>> Medication dangers

Highest sources of cysteine in milligrams per 100 grams

Rabbit (wild) 1243 mg
Soya beans 1046 mg
Sesame seeds 1012 mg
Pheasant 1007 mg
Sunflower seeds 952 mg
Chlorella (dried) 770 mg
Safflower seeds 685 mg
Mustard seeds 680 mg
Spirulina (dried) 662 mg
Oat bran 576 mg
Winged beans 545 mg
Calf’s liver 490 mg
Black walnuts 462 mg
Watermelon seeds 438 mg
Peanuts 433 mg
Pumpkin and squash seeds 404 mg
Chicken 397 mg
Quail 394 mg
Caviar (fish roe) 389 mg
Peanuts 375 mg
Whelks 374 mg
Brazil nuts 367 mg

Sesame seeds 358 mg
Flaxseeds 340 mg
Lamb’s liver 320 mg
Wheat 317 mg
Mussels 312 mg
Pine nuts 289 mg
Beef (lean mince) 278 mg
Rabbit (wild) 274 mg
Eggs 272 mg
Soya beans 268 mg
Mackerel (tinned) 249 mg
Salmon (Atlantic farmed) 237 mg
Black beans 235 mg
Shrimp/prawns 234 mg
Walnuts 209 mg
Squid 204 mg
Quinoa 203 mg
Venison 202 mg
Almonds 189 mg
Turkey 178 mg
Cheddar cheese 125 mg
Brown rice 96 mg

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