Facts
Why cystine is good for you
Cystine is a non-essential amino acid, formed from methionine and is required for proper vitamin B6 utilisation. It is also helpful in the healing of burns and wounds and helps break down mucus deposits in illnesses such as bronchitis and cystic fibrosis.
Important cystine facts
- Cystine is a crystalline, sulphur-containing amino acid, formed from two molecules of the amino acid cysteine
- Cystine is particularly abundant in skeletal and connective tissues, hair and digestive enzymes
- Cysteine also assists in the supply of insulin to the pancreas, which is needed for the assimilation of sugars and starches
- Cysteine increases the level of glutathione in the lungs, liver, kidneys and bone marrow, which may have anti-aging effects on the body by reducing age-spots
Cystine works best with
Deficiency
Groups at risk of cystine deficiency
Deficiency of cystine is rare, as it is found in so many protein foods, although in patients with chronic diseases, the synthesis of cystine from methionine appears to be prevented and could result in a deficiency. People in these groups at risk of cystine deficiency should talk to a medical professional about cystine supplementation.
Symptoms of cystine deficiency
None reported.
Health
Cystine and health
- Detoxification from cigarettes and alcohol – cystine has been shown as a detoxification agent to protect the body against damage of alcohol and cigarette smoking. It may be effective in preventing hangovers, as well as preventing liver and brain damage
Talk to a medical professional about cystine supplements before taking them
Food sources
Cystine in food
| FOOD | AMOUNT |
Cystine
(mg) |
|---|---|---|
|
Clams mixed species
|
20 small (190g) |
2166
|
|
Lean round Beef
|
450g |
1864
|
|
Lean leg of Veal
|
450g |
1426
|
|
1/2 Turkey breast – no skin
|
306g |
958
|
|
1/2 Chicken – no skin
|
329g |
902
|
|
Snapper
|
1 fillet (170g) |
479
|
|
Atlantic cod
|
1 fillet (180g) |
441
|
|
Northern pike
|
1/2 fillet (155g) |
411
|
|
Ling
|
1 fillet (151g) |
394
|
|
Lobster
|
1 cup (145g) |
334
|
|
Yellow fish tuna
|
100g |
321
|
|
Alaskan king crab
|
1 leg (172g) |
291
|
|
Blue crab
|
1 cup (118g) |
267
|
|
Pacific cod
|
1 fillet (90g) |
221
|
|
Whiting
|
1 fillet (72g) |
181
|
|
Mozzarella, part skin
|
100g |
144
|
|
Cottage cheese, 2% fat
|
100g |
127
|
|
Bacon, pan-fried
|
28g |
119
|
Daily intake
Cystine recommended daily intake (RDI)
| RDA | No information available |
|---|---|
| TOLERABLE UPPER LIMIT | No information available |
| TOXIC LEVELS | No information available |
Toxicity
Overdosage, toxicity and cautions for cystine
Diabetic patients should be careful when taking cystine supplementation, as it could inactivate their insulin medication
Precautions
Precautions
Interactions
Interactions
References
References
- Osiecki H, Meeke F, Smith J, The Encyclopaedia of Clinical Nutrition – Volume 1: The Nervous System, BioConceps Publishing QLD 2004
Last reviewed and updated: 8 May 2024