What Is Cystine & What Foods Can I Find It In?

Cystine is a non-essential amino acid, that aids in protein synthesis.

Non-essential means that our bodies can produce that amino acid, even if we don’t get it from the food we eat.

Cystine can be obtained from foods and used as a dietary supplement.

Cystine is a low cost amino acid and therefore commonly used in many areas.

Transport Of Cystine

Cystine is a sulfur-containing non-essential amino acid. (source ◳)

The transportation of cystine into the cell is essential for the synthesis of glutathione. Glutathione is an important antioxidant.

Cystine transport is also important for the maintenance of glutamic acid levels in the body. (source ◳)

Cystine is needed for the formation of glutathione and cysteine, which are precursors of other important molecules.

Uses Of Cystine

Cystine is found in both food and beverages and is used as a stabilizer for beverages and food products.

In addition to the food and beverage industries, cystine is used in the manufacture of some pharmaceutical products.

Cystine is often used in the manufacture of some nutritional supplements.

It is also commonly used in the manufacture of cosmetics. For instance, is cystine an important component of the pigment agents used in nail polish.

Cystine can also be used in some oral hygiene products such as toothpaste.

Because of the low cost to produce cystine, it is often used in nutritional supplements for cats and dogs.

Cystine As Supplements

Cystine is used as a dietary supplement to promote the healing of wounds and as a therapeutic agent in the treatment of certain diseases.

For instance, is cystine used as supplement for prevention and treatment of cystinuria.

Cystinuria is a genetic disorder in which cystine is excessively excreted in the urine.

Cystine Can Form Kidney Stones

When there is too much cystine in the urine, kidney stones can form. It is a disorder called cystinuria.

Cystine stone is a type of kidney stone, but typically larger than other kidney stones and is visible on plain radiographs. (source ◳)

Restricting dietary sodium may reduce the urinary excretion of cystine.

Also, increasing fruit and vegetable consumption may be beneficial. (source ◳)

Foods You Can Find Cystine In

You find Cystine mostly in egg, nut and seed, legume, and beef products.

Examples of food sources include

• Egg White
• Cottonseed Flour
• Cottonseed Meal
• Whole Egg
• Soy Protein Isolate
• Sesame Flour

Foods in our nutrition tool

You can find regularly updated top-ranked lists of foods for over 200+ nutrients in our nutrition tool.

If you are interested in what foods contain the most Cystine, we recommend you visit our tool.

Here's our top-ranked list of foods that contain Cystine.