The Solgar L-Cysteine 500mg is a dietary supplement in vegan capsules, with 500mg L-cysteine per capsule, in hydrochloride and free form. The package contains 30 vegan capsules, which is exactly one month at the recommended dose of one capsule per day. The product is declared by the manufacturer as vegan, gluten-free and dairy-free, with kosher certification.
It is aimed at adults who are looking for cysteine as a specific amino acid, usually because they have read or heard about its role in keratin and want something more targeted than a general preparation for hair and nails.
Keratin is the structural protein that makes up hair, nails and the outer layers of the skin. What makes it tough and resilient is not just the length of its chains but the way they are stabilized with each other. The key lies in the disulfide bonds: sulfur bridges that link two points of the protein and give it its final shape and mechanical strength.
These bridges are made by cysteine, because it is one of the few amino acids that have a free thiol group. Two molecules of cysteine join together to form a disulfide bond, which explains why keratin is extremely rich in this amino acid compared to most other proteins in the body. Cysteine is also one of the three amino acids from which the body synthesizes glutathione. It is a conditionally essential amino acid, meaning that the body can synthesize it from methionine, but this ability depends on the availability of the precursor substance. All of this is biochemistry: amino acids do not have approved health claims in the European Union.
According to the presentation of the product by Solgar itself, the preparation falls within the company's line of amino acids and is described as follows:
The above formulations are attributed to the manufacturer. L-cysteine does not have an approved health claim by the EFSA and remains a subject of research. The product does not claim an effect on the liver, heavy metal elimination or cholesterol.
The composition combines two forms of the same amino acid, hydrochloride and free L-cysteine. The hydrochloride form is chemically more stable, which is important for a molecule with a free thiol group, as this easily oxidizes in air. The presence of both forms serves to maintain the stability of the preparation over its shelf life.
The formulations are limited to the essentials: vegetable stearate magnesium and silicon dioxide as anti-caking agents, microcrystalline cellulose as a bulking agent, and a vegetable capsule shell made of hypromellose. The manufacturer's statement indicates that the product contains no sugar, salt, starch, yeast, wheat, soy or dairy products, nor preservatives, sweeteners and artificial flavors or colors. A practical detail: the dosage instruction between meals differs from most supplements, because individual amino acids compete with food amino acids for absorption.
It suits adults who are interested in the structural components of keratin and want a single-ingredient preparation with a clear dose, rather than a complex beauty formula with dozens of ingredients in unknown quantities. It suits those who follow a vegan or vegetarian diet, as the capsule is plant-based. It suits people who avoid gluten, soy or dairy. It also suits those who already take other supplements and want to add one specific amino acid.
The product is a dietary supplement and does not replace a medical diagnosis or treatment. Hair loss, skin conditions and nail disorders have many possible causes and require evaluation by a doctor, not self-management with a supplement.
Main ingredients per 1 vegan capsule: L-cysteine (as hydrochloride and in free form) 500mg.
Other ingredients: vegetable capsule shell (hypromellose), anti-caking agents (vegetable magnesium stearate, silicon dioxide), bulking agent (microcrystalline cellulose).
Free of: sugar, salt, starch, yeast, wheat, soy, gluten, dairy products, preservatives, sweeteners, artificial flavors and colors. Suitable for vegans, with kosher certification.
Form: vegan capsules
Recommended dosage: for adults, 1 vegan capsule per day, preferably with water or juice, between meals.
The 30-capsule package is sufficient for exactly 30 days, i.e. one month of use. Do not exceed the recommended daily dosage. Dietary supplements should not be used as a substitute for a balanced diet. The instruction to take between meals is not arbitrary and it is good to follow it.
People with diabetes, kidney or liver disease, as well as those with a disorder of sulfur amino acid metabolism, such as cystinuria, should consult their doctor before use. If you are pregnant or breastfeeding, taking medication or have any health problem, consult a doctor or pharmacist. Keep the product in a cool and dry place, away from children.
Because keratin, the protein from which they are made, is particularly rich in cysteine, thanks to the disulfide bonds that sulfur forms.
They are sulfur bridges between two molecules of cysteine, which stabilize the structure of the protein and give it strength.
Because individual amino acids compete with the amino acids of food proteins for absorption.
Glutathione is synthesized in the body from three amino acids, one of which is cysteine.
Such a preparation usually combines biotin, zinc and plant extracts in small doses. Here you get only one amino acid, in a declared amount of 500mg.
No. It is a different chemical form. This product contains L-cysteine in hydrochloride and free form.
Yes, the manufacturer declares the product as vegan, with a plant capsule made of hypromellose and kosher certification.
The body synthesizes cysteine from methionine, but taking two sulfur amino acids together in a supplement is something to discuss with a pharmacist.
* L-cysteine, as an amino acid, does not have an approved health claim by the EFSA under Regulation (EC) 1924/2006. The references to benefits are attributed to the manufacturer. The product is not intended for the prevention, treatment or cure of a human disease.
Nestlé Ελλάς Α.Ε.
Patroklou 4, 15125 Marousi, Athens
Tel: 800 116 80 68
Main ingredients per 1 vegan capsule: L-cysteine (as hydrochloride and in free form) 500mg.
Other ingredients: vegetable capsule shell (hypromellose), anti-caking agents (vegetable magnesium stearate, silicon dioxide), bulking agent (microcrystalline cellulose).
Free of: sugar, salt, starch, yeast, wheat, soy, gluten, dairy products, preservatives, sweeteners, artificial flavors and colors. Suitable for vegans, with kosher certification.
Form: plant capsules
Recommended dosage: for adults, 1 plant capsule daily, preferably with water or juice, between meals.
The 30-capsule package lasts exactly 30 days, i.e. one month of use. Do not exceed the recommended daily dose. Dietary supplements should not be used as a substitute for a balanced diet. The instruction to take between meals is not random and it is good to follow it.
People with diabetes, kidney or liver disease, as well as those with a disorder of sulfur amino acid metabolism, such as cystinuria, should consult their doctor before use. If you are pregnant or breastfeeding, taking medication, or have any health problem, consult a doctor or pharmacist. Keep the product in a cool and dry place, away from children.
