L-Cysteine 500 mg
NOW
L-Cysteine 500 mg
4.4
★ ★ ★ ★ ★
(18851 ratings)
Vitamin B6 10 mg
Cysteine 500 mg
Score 85.0
A highly effective and well-priced L-Cysteine supplement from a reputable brand, featuring a supportive dose of Vitamin B6. It excels in supporting detoxification, skin, and hair health, backed by strong user reviews.
Quantity: 100 Tablet(s)Servings size: 1 Tablet(s) (100 servings)
Selected goals:
Other goals:
Energy
Brain Health
Mood Support
General Health
Immunity
leaderboard Score 85.0
A highly effective and well-priced L-Cysteine supplement from a reputable brand, featuring a supportive dose of Vitamin B6. It excels in supporting detoxification, skin, and hair health, backed by strong user reviews.
insights Analysis
NOW L-Cysteine 500 mg is a well-formulated supplement designed to leverage the benefits of L-Cysteine, a semi-essential amino acid, and Vitamin B6. L-Cysteine is crucial for the synthesis of glutathione, the body's 'master antioxidant,' and keratin, a primary structural protein found in hair, skin, and nails. The inclusion of Vitamin B6 (Pyridoxine Hydrochloride) is strategic, as it acts as a cofactor in numerous enzymatic reactions, including those involved in amino acid metabolism and the transsulfuration pathway, which supports cysteine and glutathione production. The 500mg dose of L-Cysteine is standard and therapeutically relevant, while 10mg of B6 is sufficient for its supporting role. This product excels in its primary functions related to antioxidant defense, detoxification, and the structural integrity of hair and skin, making it a reliable choice for these specific health goals.
- Contains a clinically relevant and effective dose of L-Cysteine (500mg) for glutathione and keratin synthesis.
- Includes Vitamin B6, a crucial cofactor that enhances the body's utilization of L-Cysteine and supports overall metabolic processes.
- Manufactured by NOW, a highly reputable brand known for quality, purity, and rigorous testing.
- Excellent value with a competitive price per serving and a large number of servings (100).
- Very high review count with overwhelmingly positive feedback, indicating widespread user satisfaction and perceived efficacy.
- Uses Pyridoxine Hydrochloride for Vitamin B6, which is effective but some individuals may prefer the more bioavailable form, Pyridoxal-5-Phosphate (P-5-P).
- While L-Cysteine supports glutathione production, some users might find N-Acetyl Cysteine (NAC) to be a more direct and readily absorbable precursor for glutathione synthesis.
- As a targeted supplement, it may not provide comprehensive benefits for all health goals without additional supplementation, particularly for energy or general mood support.
$12.10($0.12 per serving)
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bolt Effectiveness for goals
Yes, Cysteine, particularly in its N-acetylcysteine (NAC) form, is highly effective as an antioxidant. It is a direct precursor to glutathione, a major endogenous antioxidant. By boosting glutathione levels, NAC helps neutralize free radicals and reduce oxidative stress.
Cysteine, commonly supplemented as N-acetylcysteine (NAC), is primarily effective as a precursor to glutathione, a powerful antioxidant in the body. It supports detoxification processes and lung health by helping to thin mucus. NAC also has roles in liver support and immune function.
Vitamin B6, or pyridoxine, is effective in numerous bodily functions, including protein, fat, and carbohydrate metabolism, and the creation of red blood cells and neurotransmitters. It plays a role in brain development, nerve function, and immune health. Evidence supports its use for specific conditions like morning sickness and premenstrual syndrome.
Yes, Cysteine (NAC) has well-documented benefits for liver support. Its ability to replenish glutathione is crucial for the liver's detoxification pathways. It can help protect liver cells from damage and is used in clinical settings for certain types of liver injury.
Vitamin B6 is a water-soluble vitamin essential for over 100 enzyme reactions, mainly involved in protein, fat, and carbohydrate metabolism. It plays a critical role in brain development, immune function, and forming red blood cells. It also helps in the production of neurotransmitters.
schedule Dosage, timing & forms
Typical daily dosages for N-Acetyl Cysteine (NAC) in supplements often range from 600 mg to 1800 mg. Dosages can vary based on the intended use and individual response, with some protocols suggesting higher amounts under professional supervision.
For adults, the Recommended Dietary Allowance (RDA) for Vitamin B6 is 1.3-1.7 mg per day. Supplemental dosages often range from 10 mg to 100 mg daily, depending on individual needs and health goals, under professional guidance.
Yes, Vitamin B6, specifically in its active P-5-P form, is a crucial cofactor for enzymes involved in the transsulfuration pathway. This pathway is essential for the metabolism of sulfur-containing amino acids, including cysteine. Therefore, adequate B6 levels can support the efficient processing of cysteine and NAC in the body.
The most common supplemental form of cysteine is N-acetylcysteine (NAC). L-cysteine is also available but is less commonly used as a standalone supplement compared to NAC, which is highly bioavailable.
Vitamin B6 is commonly available in two forms: pyridoxine hydrochloride (pyridoxine HCl) and pyridoxal-5-phosphate (P-5-P). Pyridoxine HCl is the most common form, while P-5-P is the active coenzyme form ready for use by the body.
health_and_safety Safety & interactions
High doses of Vitamin B6 (pyridoxine) can lead to sensory neuropathy, characterized by nerve damage, numbness, and tingling in the hands and feet. Other potential side effects may include skin lesions, photosensitivity, and gastrointestinal upset. These effects are typically associated with chronic intake exceeding the established upper limit.
Yes, the National Academy of Medicine has set an Upper Tolerable Intake Level (UL) for Vitamin B6 at 100 mg per day for adults. Consuming amounts above this UL, especially over long periods, increases the risk of adverse effects, such as peripheral neuropathy.
Common side effects of N-acetylcysteine (NAC) can include gastrointestinal issues such as nausea, vomiting, diarrhea, or constipation. Some individuals may also experience skin rashes or drowsiness. These effects are usually mild and tend to resolve with continued use or a lower dose.
Yes, Vitamin B6 can interact with several medications. For instance, it may reduce the effectiveness of levodopa (used for Parkinson's disease) and can interact with anti-seizure medications like phenytoin and phenobarbital, potentially altering their concentrations. Always consult a healthcare professional regarding supplement and medication interactions.
N-acetylcysteine (NAC) may possess some antiplatelet effects, which could theoretically increase the risk of bleeding in some individuals. Therefore, caution is advised if taking NAC with blood-thinning medications like warfarin or aspirin. Monitoring by a healthcare professional may be necessary.
Ingredients
| Ingredient | Amount per serving |
|---|---|
Vitamin C | 60 mg |
Vitamin B6 | 10 mg |
L-Cysteine Hydrochloride | 500 mg |
Categories
Cysteine 85.0
Delivering 500mg of L-Cysteine Hydrochloride per serving, this product offers a potent and widely recognized dose for supporting glutathione production, keratin formation, and various metabolic functions.
Vitamin B6 75.0
The product provides 10mg of Vitamin B6 as Pyridoxine Hydrochloride, a standard and effective form that adequately supports the cofactor roles of L-Cysteine metabolism and neurotransmitter synthesis, though some prefer the P-5-P form for bioavailability.
Goals
Detoxification 90.0
This product excels in detoxification support as L-Cysteine is a direct and essential precursor for glutathione, the body's primary antioxidant and detoxifying agent, crucial for liver health and removing toxins.
Hair Health 90.0
As a primary constituent of keratin, the main protein forming hair strands, L-Cysteine is directly instrumental in supporting hair strength, growth, and overall structural integrity and health.
Skin Health 85.0
L-Cysteine is a fundamental building block of keratin, a major structural protein in skin, promoting its strength and elasticity. Glutathione, supported by L-Cysteine, also helps protect skin cells from oxidative damage and environmental stressors.
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