The World's Leading Skincare Glossary, brought to you by Lesielle

The 1st Customized Skincare System that Adapts to YOUR Changing Needs


INCI: Cysteine

What is Cysteine ?

Cysteine is a sulfur-containing amino acid, it is naturally found in almost every living organisms, especially those who have keratin in any form in their structure. Cystine is again an amino acid, but it is a molecule that is formed from two cysteine molecules joining together with a disulfide bond. It can be considered as a storage form of cysteine in our body. Cysteine can be fully synthesized to use in cosmetics or other medicinal uses from genetically engineered bacteria.

Use & Benefits:

Cysteine is a powerful antioxidant with potential to trap ROS. However cysteine in its natural form cannot exert its effect, so it has to get converted into acetylcysteine. It also produces a whitening effect. It affects in melanin production pathway in such a manner that it decreases the skin darkening melanin synthesis. Because of the sulfide group, it is also used as a reducing agent in many cosmetic preparations. Considering its chemical structure, it has much to offer in case of hair conditioning. It forms bonds and forms a thin layer over the hair shaft to produce an antistatic and conditioning effect. It is mainly used in creams and lotions and majority in hair preparations.

How to create your own Personalized Skincare with Lesielle?

Icons of the lesielle custom skin care system

Step 1: Select a nourishing base compatible with your skin, and your desired moisturization level

Step 2: Complete your treatment with up to four active ingredients for consistent and occasional use.

Step 3: Insert your base and up to four actives ingredients into your Lesielle device to produce a fresh single dose of face cream on demand when you need it.

Complete your routine with a cleanser and other complimentary products and accessories.


Don't you know what Base and Actives your skin needs?

Take our personalized skincare quiz.

Notice: the information collected here is limited in terms of use and scope. See terms and conditions.

The skincare system for an ever evolving skin, using recognized active ingredients with scientifically proven efficacy to create treatment tailored to each day's State of Skin. 

  • All rights reserved 2023